Add GHC-9.2.0.20210821 rc1

Merge branch 'fixes'
Clean up CI
2021-08-23 13:16:18 +02:00 · 2021-08-21 14:46:43 +02:00 · 2021-08-21 14:34:47 +02:00 · 2021-08-21 14:28:53 +02:00 · 2021-08-21 14:28:31 +02:00 · 2021-08-21 09:28:56 +02:00
43 changed files with 27792 additions and 729 deletions
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -99,11 +99,12 @@ variables:
  script:
    - bash ./.gitlab/script/ghcup_version.sh
  variables:
-    JSON_VERSION: "0.0.5"
+    JSON_VERSION: "0.0.6"
  artifacts:
    expire_in: 2 week
    paths:
      - golden
+      - dist-newstyle/cache/
    when: on_failure

 # .test_ghcup_scoop:
@@ -202,10 +203,11 @@ variables:
    expire_in: 2 week
    paths:
      - out
+      - dist-newstyle/cache/
  only:
    - tags
  variables:
-    JSON_VERSION: "0.0.5"
+    JSON_VERSION: "0.0.6"

 ######## stack test ########

@@ -228,7 +230,7 @@ test:linux:bootstrap_script:
  script:
    - ./.gitlab/script/ghcup_bootstrap.sh
  variables:
-    GHC_VERSION: "8.10.5"
+    GHC_VERSION: "8.10.6"
    CABAL_VERSION: "3.4.0.0"
  extends:
    - .debian
@@ -245,7 +247,7 @@ test:windows:bootstrap_powershell_script:
    - "[Environment]::SetEnvironmentVariable('CABAL_DIR', $null, [System.EnvironmentVariableTarget]::User)"
    - bash ./.gitlab/after_script.sh
  variables:
-    GHC_VERSION: "8.10.5"
+    GHC_VERSION: "8.10.6"
    CABAL_VERSION: "3.4.0.0"
  extends:
    - .windows
@@ -253,19 +255,11 @@ test:windows:bootstrap_powershell_script:

 ######## linux test ########

-test:linux:recommended:
+test:linux:
  stage: test
  extends: .test_ghcup_version:linux
  variables:
-    GHC_VERSION: "8.10.5"
-    CABAL_VERSION: "3.4.0.0"
-  needs: []
-
-test:linux:latest:
-  stage: test
-  extends: .test_ghcup_version:linux
-  variables:
-    GHC_VERSION: "9.0.1"
+    GHC_VERSION: "8.10.6"
    CABAL_VERSION: "3.4.0.0"
  needs: []

@@ -275,8 +269,8 @@ test:linux:cross-armv7:
    - .test_ghcup_version
    - .debian
  variables:
-    GHC_VERSION: "8.10.4"
-    GHC_TARGET_VERSION: "8.10.5"
+    GHC_VERSION: "8.10.5"
+    GHC_TARGET_VERSION: "8.10.6"
    CABAL_VERSION: "3.4.0.0"
    CROSS: "arm-linux-gnueabihf"
  needs: []
@@ -293,7 +287,7 @@ test:linux:git:hadrian:
    - .test_ghcup_version
    - .debian
  variables:
-    GHC_VERSION: "8.10.5"
+    GHC_VERSION: "8.10.6"
    GHC_GIT_TAG: "ghc-9.0.1-release"
    GHC_GIT_VERSION: "9.0.1"
    CABAL_VERSION: "3.4.0.0"
@@ -309,17 +303,17 @@ test:linux:git:hadrian:

 ######## linux 32bit test ########

-test:linux:recommended:32bit:
+test:linux:32bit:
  stage: test
  extends: .test_ghcup_version:linux32
  variables:
-    GHC_VERSION: "8.10.5"
+    GHC_VERSION: "8.10.6"
    CABAL_VERSION: "3.2.0.0"
  needs: []

 ######## arm tests ########

-test:linux:recommended:armv7:
+test:linux:armv7:
  stage: test
  extends: .test_ghcup_version:armv7
  variables:
@@ -329,7 +323,7 @@ test:linux:recommended:armv7:
  when: manual
  needs: []

-test:linux:recommended:aarch64:
+test:linux:aarch64:
  stage: test
  extends: .test_ghcup_version:aarch64
  variables:
@@ -341,7 +335,7 @@ test:linux:recommended:aarch64:

 ######## darwin test ########

-test:mac:recommended:
+test:mac:
  stage: test
  extends: .test_ghcup_version:darwin
  variables:
@@ -349,19 +343,11 @@ test:mac:recommended:
    CABAL_VERSION: "3.4.0.0"
  needs: []

-test:mac:latest:
-  stage: test
-  extends: .test_ghcup_version:darwin
-  variables:
-    GHC_VERSION: "9.0.1"
-    CABAL_VERSION: "3.4.0.0"
-  needs: []
-
-test:mac:recommended:aarch64:
+test:mac:aarch64:
  stage: test
  extends: .test_ghcup_version:darwin:aarch64
  variables:
-    GHC_VERSION: "8.10.5"
+    GHC_VERSION: "8.10.6"
    CABAL_VERSION: "3.4.0.0"
  needs: []
  allow_failure: true
@@ -369,7 +355,7 @@ test:mac:recommended:aarch64:

 ######## freebsd test ########

-test:freebsd:recommended:
+test:freebsd:
  stage: test
  extends: .test_ghcup_version:freebsd
  variables:
@@ -381,11 +367,11 @@ test:freebsd:recommended:

 ######## windows test ########

-test:windows:recommended:
+test:windows:
  stage: test
  extends: .test_ghcup_version:windows
  variables:
-    GHC_VERSION: "8.10.5"
+    GHC_VERSION: "8.10.6"
    CABAL_VERSION: "3.4.0.0"
  needs: []

@@ -398,7 +384,7 @@ test:windows:recommended:

 release:linux:64bit:
  stage: release
-  needs: ["test:linux:recommended", "test:linux:latest"]
+  needs: ["test:linux"]
  extends:
    - .alpine:64bit
    - .release_ghcup
@@ -406,13 +392,13 @@ release:linux:64bit:
    - ./.gitlab/before_script/linux/alpine/install_deps.sh
  variables:
    ARTIFACT: "x86_64-linux-ghcup"
-    GHC_VERSION: "8.10.5"
+    GHC_VERSION: "8.10.6"
    CABAL_VERSION: "3.4.0.0"


 release:linux:32bit:
  stage: release
-  needs: ["test:linux:recommended:32bit"]
+  needs: ["test:linux:32bit"]
  extends:
    - .alpine:32bit
    - .release_ghcup
@@ -420,12 +406,12 @@ release:linux:32bit:
    - ./.gitlab/before_script/linux/alpine/install_deps.sh
  variables:
    ARTIFACT: "i386-linux-ghcup"
-    GHC_VERSION: "8.10.5"
+    GHC_VERSION: "8.10.6"
    CABAL_VERSION: "3.2.0.0"

 release:linux:armv7:
  stage: release
-  needs: ["test:linux:recommended:armv7"]
+  needs: ["test:linux:armv7"]
  extends:
    - .linux:armv7
    - .release_ghcup
@@ -439,7 +425,7 @@ release:linux:armv7:

 release:linux:aarch64:
  stage: release
-  needs: ["test:linux:recommended:aarch64"]
+  needs: ["test:linux:aarch64"]
  extends:
    - .linux:aarch64
    - .release_ghcup
@@ -455,7 +441,7 @@ release:linux:aarch64:

 release:darwin:
  stage: release
-  needs: ["test:mac:recommended", "test:mac:latest"]
+  needs: ["test:mac"]
  extends:
    - .darwin
    - .release_ghcup
@@ -464,13 +450,13 @@ release:darwin:
    - ./.gitlab/before_script/darwin/install_deps.sh
  variables:
    ARTIFACT: "x86_64-apple-darwin-ghcup"
-    GHC_VERSION: "8.10.5"
+    GHC_VERSION: "8.10.6"
    CABAL_VERSION: "3.4.0.0"
    MACOSX_DEPLOYMENT_TARGET: "10.7"

 release:darwin:aarch64:
  stage: release
-  needs: ["test:mac:recommended:aarch64"]
+  needs: ["test:mac:aarch64"]
  extends:
    - .darwin:aarch64
    - .release_ghcup
@@ -497,7 +483,7 @@ release:darwin:aarch64:
    runInNixShell ./.gitlab/script/ghcup_release.sh 2>&1
  variables:
    ARTIFACT: "aarch64-apple-darwin-ghcup"
-    GHC_VERSION: "8.10.5"
+    GHC_VERSION: "8.10.6"
    CABAL_VERSION: "3.4.0.0"
    MACOSX_DEPLOYMENT_TARGET: "10.7"
  allow_failure: true
@@ -507,7 +493,7 @@ release:darwin:aarch64:

 release:freebsd:
  stage: release
-  needs: ["test:freebsd:recommended"]
+  needs: ["test:freebsd"]
  extends:
    - .freebsd
    - .release_ghcup
@@ -516,7 +502,7 @@ release:freebsd:
    - ./.gitlab/before_script/freebsd/install_deps.sh
  variables:
    ARTIFACT: "x86_64-portbld-freebsd-ghcup"
-    GHC_VERSION: "8.10.5"
+    GHC_VERSION: "8.10.6"
    CABAL_VERSION: "3.4.0.0"
  allow_failure: true

@@ -524,7 +510,7 @@ release:freebsd:

 release:windows:
  stage: release
-  needs: ["test:windows:recommended"]
+  needs: ["test:windows"]
  extends:
    - .windows
    - .release_ghcup
@@ -533,7 +519,7 @@ release:windows:
    - bash ./.gitlab/before_script/windows/install_deps.sh
  variables:
    ARTIFACT: "x86_64-mingw64-ghcup"
-    GHC_VERSION: "8.10.5"
+    GHC_VERSION: "8.10.6"
    CABAL_VERSION: "3.4.0.0"

 ######## hlint ########
@@ -547,7 +533,7 @@ hlint:
  script:
    - ./.gitlab/script/hlint.sh
  variables:
-    GHC_VERSION: "8.10.5"
+    GHC_VERSION: "8.10.6"
    CABAL_VERSION: "3.4.0.0"
    JSON_VERSION: "0.0.4"
  allow_failure: true
--- a/.gitlab/before_script/darwin/install_deps.sh
+++ b/.gitlab/before_script/darwin/install_deps.sh
@@ -7,7 +7,7 @@ set -eux
 mkdir -p "${TMPDIR}"

 if [ $ARCH = 'ARM64' ] ; then
-	curl -sSfL https://downloads.haskell.org/~ghcup/0.1.15.1/aarch64-apple-darwin-ghcup-0.1.15.1 > ./ghcup-bin
+	curl -sSfL https://downloads.haskell.org/~ghcup/aarch64-apple-darwin-ghcup > ./ghcup-bin
 	chmod +x ghcup-bin
 else
 	curl -sSfL https://downloads.haskell.org/~ghcup/x86_64-apple-darwin-ghcup > ./ghcup-bin
--- a/.gitlab/before_script/windows/install_deps.sh
+++ b/.gitlab/before_script/windows/install_deps.sh
@@ -9,7 +9,7 @@ mkdir -p "${TMPDIR}" "${CABAL_DIR}"
 mkdir -p "$GHCUP_INSTALL_BASE_PREFIX/ghcup/bin"

 CI_PROJECT_DIR=$(pwd)
-curl -o ghcup.exe https://downloads.haskell.org/~ghcup/0.1.15.1/x86_64-mingw64-ghcup-0.1.15.1.exe
+curl -o ghcup.exe https://downloads.haskell.org/~ghcup/x86_64-mingw64-ghcup.exe
 chmod +x ghcup.exe

 ./ghcup.exe install ${GHC_VERSION}
--- a/.gitlab/ghc-8.10.3-linux.files
+++ b/.gitlab/ghc-8.10.3-linux.files
--- a/.gitlab/ghc-8.10.3-windows.files
+++ b/.gitlab/ghc-8.10.3-windows.files
--- a/.gitlab/script/ghcup_version.sh
+++ b/.gitlab/script/ghcup_version.sh
@@ -12,6 +12,10 @@ ecabal() {
 	cabal "$@"
 }

+raw_eghcup() {
+	ghcup -v -c "$@"
+}
+
 eghcup() {
 	if [ "${OS}" = "WINDOWS" ] ; then
 		ghcup -v -c -s file:/$CI_PROJECT_DIR/ghcup-${JSON_VERSION}.yaml "$@"
@@ -20,6 +24,12 @@ eghcup() {
 	fi
 }

+if [ "${OS}" = "WINDOWS" ] ; then
+	GHCUP_DIR="${GHCUP_INSTALL_BASE_PREFIX}"/ghcup
+else
+	GHCUP_DIR="${GHCUP_INSTALL_BASE_PREFIX}"/.ghcup
+fi
+
 git describe --always

 ### build
@@ -65,11 +75,7 @@ fi

 ### cleanup

-if [ "${OS}" = "WINDOWS" ] ; then
-	rm -rf "${GHCUP_INSTALL_BASE_PREFIX}"/ghcup
-else
-	rm -rf "${GHCUP_INSTALL_BASE_PREFIX}"/.ghcup
-fi
+rm -rf "${GHCUP_DIR}"

 ### manual cli based testing

@@ -88,6 +94,7 @@ cabal --version

 eghcup debug-info

+# also test etags
 eghcup list
 eghcup list -t ghc
 eghcup list -t cabal
@@ -109,7 +116,20 @@ else
 	if [ "${OS}" = "LINUX" ] ; then
 		eghcup --downloader=wget prefetch ghc 8.10.3
 		eghcup --offline install ghc 8.10.3
-	else # test wget a bit
+		if [ "${ARCH}" = "64" ] ; then
+			expected=$(cat "$( cd "$(dirname "$0")" ; pwd -P )/../ghc-8.10.3-linux.files" | sort)
+			actual=$(cd "${GHCUP_DIR}/ghc/8.10.3/" && find | sort)
+			[ "${actual}" = "${expected}" ]
+			unset actual expected
+		fi
+	elif [ "${OS}" = "WINDOWS" ] ; then
+		eghcup prefetch ghc 8.10.3
+		eghcup --offline install ghc 8.10.3
+		expected=$(cat "$( cd "$(dirname "$0")" ; pwd -P )/../ghc-8.10.3-windows.files" | sort)
+		actual=$(cd "${GHCUP_DIR}/ghc/8.10.3/" && find | sort)
+		[ "${actual}" = "${expected}" ]
+		unset actual expected
+	else
 		eghcup prefetch ghc 8.10.3
 		eghcup --offline install ghc 8.10.3
 	fi
@@ -155,6 +175,55 @@ if [ "${OS}" = "LINUX" ] ; then
 	fi
 fi

+sha_sum() {
+	if [ "${OS}" = "FREEBSD" ] ; then
+		sha256 "$@"
+	else
+		sha256sum "$@"
+	fi
+
+}
+
+# test etags
+rm -f "${GHCUP_DIR}/cache/ghcup-${JSON_VERSION}.yaml"
+raw_eghcup -s https://www.haskell.org/ghcup/data/ghcup-${JSON_VERSION}.yaml list
+# snapshot yaml and etags file
+etag=$(cat "${GHCUP_DIR}/cache/ghcup-${JSON_VERSION}.yaml.etags")
+sha=$(sha_sum "${GHCUP_DIR}/cache/ghcup-${JSON_VERSION}.yaml")
+# invalidate access time timer, which is 5minutes, so we re-download
+touch -a -m -t '199901010101' "${GHCUP_DIR}/cache/ghcup-${JSON_VERSION}.yaml"
+# redownload same file with some newlines added
+raw_eghcup -s https://www.haskell.org/ghcup/exp/ghcup-${JSON_VERSION}.yaml list
+# snapshot new yaml and etags file
+etag2=$(cat "${GHCUP_DIR}/cache/ghcup-${JSON_VERSION}.yaml.etags")
+sha2=$(sha_sum "${GHCUP_DIR}/cache/ghcup-${JSON_VERSION}.yaml")
+# compare
+[ "${etag}" != "${etag2}" ]
+[ "${sha}" != "${sha2}" ]
+# invalidate access time timer, which is 5minutes, but don't expect a re-download
+touch -a -m -t '199901010101' "${GHCUP_DIR}/cache/ghcup-${JSON_VERSION}.yaml"
+# this time, we expect the same hash and etag
+raw_eghcup -s https://www.haskell.org/ghcup/exp/ghcup-${JSON_VERSION}.yaml list
+etag3=$(cat "${GHCUP_DIR}/cache/ghcup-${JSON_VERSION}.yaml.etags")
+sha3=$(sha_sum "${GHCUP_DIR}/cache/ghcup-${JSON_VERSION}.yaml")
+[ "${etag2}" = "${etag3}" ]
+[ "${sha2}" = "${sha3}" ]
+
+# test isolated installs
+eghcup install ghc -i "$(pwd)/isolated" 8.10.5
+[ "$(isolated/bin/ghc --numeric-version)" = "8.10.5" ]
+! eghcup install ghc -i "$(pwd)/isolated" 8.10.5
+if [ "${ARCH}" = "64" ] ; then
+	if [ "${OS}" = "LINUX" ] || [ "${OS}" = "WINDOWS" ] ; then
+		eghcup install cabal -i "$(pwd)/isolated" 3.4.0.0
+		[ "$(isolated/cabal --numeric-version)" = "3.4.0.0" ]
+		eghcup install stack -i "$(pwd)/isolated" 2.7.3
+		[ "$(isolated/stack --numeric-version)" = "2.7.3" ]
+		eghcup install hls -i "$(pwd)/isolated" 1.3.0
+		[ "$(isolated/haskell-language-server-wrapper --numeric-version)" = "1.3.0" ] ||
+			[ "$(isolated/haskell-language-server-wrapper --numeric-version)" = "1.3.0.0" ]
+	fi
+fi

 eghcup upgrade
 eghcup upgrade -f
@@ -162,8 +231,4 @@ eghcup upgrade -f

 # nuke
 eghcup nuke
-if [ "${OS}" = "WINDOWS" ] ; then
-	[ ! -e "${GHCUP_INSTALL_BASE_PREFIX}/ghcup" ]
-else
-	[ ! -e "${GHCUP_INSTALL_BASE_PREFIX}/.ghcup" ]
-fi
+[ ! -e "${GHCUP_DIR}" ]
--- a/.gitlab/shell.nix
+++ b/.gitlab/shell.nix
@@ -43,6 +43,7 @@

  # unconditionally add the MacOSX.sdk and TargetConditional.h
  export NIX_CFLAGS_COMPILE+=" -isystem /Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/include"
+  export NIX_LDFLAGS="-L/Library/Developer/CommandLineTools/SDKs/MacOSX.sdk/usr/lib $NIX_LDFLAGS"

  '';

--- a/.travis.yml
+++ b/.travis.yml
@@ -0,0 +1,25 @@
+jobs:
+  include:
+    - os: osx
+      osx_image: xcode10.1
+      language: generic
+      env: ARTIFACT=x86_64-apple-darwin-10.13-ghcup
+
+    - os: osx
+      osx_image: xcode11.3
+      language: generic
+      env: ARTIFACT=x86_64-apple-darwin-10.14-ghcup
+
+
+script: ".travis/build.sh"
+
+deploy:
+  provider: releases
+  api_key:
+    secure: "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"
+  file: $ARTIFACT
+  on:
+    repo: hasufell/ghcup-hs
+    tags: true
+  skip_cleanup: true
+  draft: true
--- a/.travis/build.sh
+++ b/.travis/build.sh
@@ -0,0 +1,28 @@
+#!/bin/sh
+
+set -ex
+
+mkdir -p ~/.ghcup/bin
+curl -sSfL https://downloads.haskell.org/~ghcup/x86_64-apple-darwin-ghcup > ~/.ghcup/bin/ghcup
+chmod +x ~/.ghcup/bin/ghcup
+
+export PATH="$HOME/.ghcup/bin:$PATH"
+
+ghcup install 8.10.4
+ghcup install-cabal 3.4.0.0
+ghcup set 8.10.4
+
+
+## install ghcup
+
+cabal update
+
+(
+       cd /tmp
+       cabal install --installdir="$HOME"/.ghcup/bin hspec-discover
+)
+
+cabal build --constraint="zlib +static" --constraint="lzma +static" -ftui
+cp "$(cabal new-exec --verbose=0 --offline sh -- -c 'command -v ghcup')" .
+strip ./ghcup
+cp ghcup "./${ARTIFACT}"
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,8 +1,32 @@
 # Revision history for ghcup

-## 0.1.16 -- ????-??-??
+## 0.1.16.2 -- 2021-08-12
+
+* Add isolated installations wrt [#141](https://gitlab.haskell.org/haskell/ghcup-hs/-/merge_requests/141) by Arjun Kathuria
+* Implement config cli MVP wrt [#134](https://gitlab.haskell.org/haskell/ghcup-hs/-/merge_requests/134) by Oleksii Dorozhkin
+* Fix `ghcup compile ghc --flavor`
+* Fix minor installation bug causing increased disk space wrt [#139](https://gitlab.haskell.org/haskell/ghcup-hs/-/merge_requests/139)
+* Improved error handling wrt [#136](https://gitlab.haskell.org/haskell/ghcup-hs/-/merge_requests/136)
+* Various improvements to metadata download when using `file://` and `--offline` wrt [#137](https://gitlab.haskell.org/haskell/ghcup-hs/-/merge_requests/137)
+
+## 0.1.16.1 -- 2021-07-29

 * Add 'nuke' subcommand wrt [#135](https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/135), implemented by Arjun Kathuria
+* Add uninstallation powershell script on windows wrt [#150](https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/150)
+* Improve logging
+* Fix building GHC cross compiler wrt [#180](https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/180)
+* Allow to use hadrian as build system (for git based versions only) wrt [#35](https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/35)
+* Allow passing `--flavor` to `ghcup compile ghc`
+* Support new GHC `bin/` directory format wrt [ghc/ghc#20074](https://gitlab.haskell.org/ghc/ghc/-/issues/20074#note_363720)
+* Implement `whereis` subcommand wrt [#173](https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/173)
+* Add `--offline` switch and `prefetch` subcommand wrt [#186](https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/186)
+* Implement ETAGs hashing for metadata downloads to speed up `ghcup list` wrt [#193](https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/193)
+* Avoid unnecessary fetching of ghcup metadata in some commands
+* Avoid unnecessary update checks for some commands
+* Preserve mtimes on unpacked GHC tarballs on windows wrt [#187](https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/187), fixing issues with `ghc-pkg`
+* Fix lesser bug in `ghcup list` for stray stack versions wrt [#183](https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/183)
+* Major redo on how file removal on windows works, avoiding partial removals etc, wrt [#165](https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/165)
+* Improve ghcup tui for screen readers wrt [github/#4](https://github.com/haskell/ghcup-hs/pull/4), thanks to Mario Lang

 ## 0.1.15.2 -- 2021-06-13

--- a/README.md
+++ b/README.md
@@ -6,6 +6,11 @@ Similar in scope to [rustup](https://github.com/rust-lang-nursery/rustup.rs), [p

 ## Table of Contents

+[![Join the chat at Libera.chat](https://img.shields.io/badge/chat-on%20libera%20IRC-brightgreen.svg)](https://kiwiirc.com/nextclient/irc.libera.chat/?nick=Guest%7C?#haskell,#haskell-ghcup)
+[![Join the chat at Matrix.org](https://img.shields.io/matrix/haskell-tooling:matrix.org?label=chat%20on%20matrix.org)](https://app.element.io/#/room/#haskell-tooling:matrix.org)
+[![Join the chat at Discord](https://img.shields.io/discord/280033776820813825?label=chat%20on%20discord)](https://discord.gg/pKYf3zDQU7)
+[![Join the chat at https://gitter.im/haskell/ghcup](https://badges.gitter.im/haskell/ghcup.svg)](https://gitter.im/haskell/ghcup?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge)
+
   * [Installation](#installation)
     * [Simple bootstrap](#simple-bootstrap)
     * [Manual install](#manual-install)
@@ -18,6 +23,8 @@ Similar in scope to [rustup](https://github.com/rust-lang-nursery/rustup.rs), [p
     * [XDG support](#xdg-support)
     * [Env variables](#env-variables)
     * [Installing custom bindists](#installing-custom-bindists)
+     * [Isolated Installs](#isolated-installs)
+     * [Tips and tricks](#tips-and-tricks)
   * [Design goals](#design-goals)
   * [How](#how)
   * [Known users](#known-users)
@@ -154,6 +161,83 @@ and produce the binaries `ghc-8.10.2-eff` and `ghc-head` respectively.
 GHCup always needs to know which version the bindist corresponds to (this is not automatically
 detected).

+### Isolated installs
+
+Ghcup also enables you to install a tool (GHC, Cabal, HLS, Stack) at an isolated location of your choosing.
+These installs, as the name suggests, are separate from your main installs and DO NOT conflict with them.
+
+
+- No symlinks are made to these isolated installed tools, you'd have to manually point to them wherever you intend to use them.
+
+- These installs, can also NOT be deleted from ghcup, you'd have to go and manually delete these.
+
+You need to use the `--isolate` or `-i` flag followed by the directory path.
+
+Examples:-
+
+1. install an isolated GHC version at location /home/user/isolated_dir/ghc/  
+   - `ghcup install ghc 8.10.5 --isolate /home/user/isolated_dir/ghc`
+
+2. isolated install Cabal at a location you desire  
+   - `ghcup install cabal --isolate /home/username/my_isolated_dir/`
+
+3. do an isolated install with a custom bindist  
+   - `ghcup install ghc --isolate /home/username/my_isolated_dir/ -u 'https://gitlab.haskell.org/api/v4/projects/1/jobs/artifacts/master/raw/ghc-x86_64-fedora27-linux.tar.xz?job=validate-x86_64-linux-fedora27' head`
+
+4. isolated install HLS  
+   - `ghcup install hls --isolate /home/username/dir/hls/`
+
+5. you can even compile ghc to an isolated location.  
+   - `ghcup compile ghc -j 4 -v 9.0.1 -b 8.10.5 -i /home/username/my/dir/ghc` 
+   ---  
+   
+### Tips and tricks
+
+#### with_ghc wrapper (e.g. for HLS)
+
+Due to some HLS [bugs](https://github.com/mpickering/hie-bios/issues/194) it's necessary that the `ghc` in PATH
+is the one defined in `cabal.project`. With some simple shell functions, we can start our editor with the appropriate
+path prepended.
+
+For bash, in e.g. `~/.bashrc` define:
+
+```sh
+with_ghc() {
+  local np=$(ghcup --offline whereis -d ghc $1 || { ghcup --cache install ghc $1 && ghcup whereis -d ghc $1 ;})
+  if [ -e "${np}" ] ; then
+    shift
+    PATH="$np:$PATH" "$@"
+  else
+    >&2 echo "Cannot find or install GHC version $1"
+    return 1
+  fi
+}
+```
+
+For fish shell, in e.g. `~/.config/fish/config.fish` define:
+
+```fish
+function with_ghc
+  set --local np (ghcup --offline whereis -d ghc $argv[1] ; or begin ghcup --cache install ghc $argv[1] ; and ghcup whereis -d ghc $argv[1] ; end)
+  if test -e "$np"
+    PATH="$np:$PATH" $argv[2..-1]
+  else
+    echo "Cannot find or install GHC version $argv[1]" 1>&2
+    return 1
+  end
+end
+```
+
+Then start a new shell and issue:
+
+```sh
+# replace 'code' with your editor
+with_ghc 8.10.5 code path/to/haskell/source
+```
+
+Cabal and HLS will now see `8.10.5` as the primary GHC, without the need to
+run `ghcup set` all the time when switching between projects.
+
 ## Design goals

 1. simplicity
@@ -230,16 +314,110 @@ to figure out whether you have the correct toolchain and
 the correct dependencies. Refer to [the official docs](https://ghc.haskell.org/trac/ghc/wiki/Building/Preparation/Linux)
 on how to prepare your environment for building GHC.

+### Stack support
+
+There may be a number of bugs when trying to make ghcup installed GHC versions work with stack,
+such as:
+
+- https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/188
+
+Further, stack's upgrade procedure may break/confuse ghcup. There are a number of integration
+issues discussed here:
+
+- https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/153
+
+### Windows support
+
+Windows support is in early stages. Since windows doesn't support symbolic links properly,
+ghcup uses a [shimgen wrapper](https://github.com/71/scoop-better-shimexe). It seems to work
+well, but there may be unknown issues with that approach.
+
+Windows 7 and Powershell 2.0 aren't well supported at the moment, also see:
+
+- https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/140
+- https://gitlab.haskell.org/haskell/ghcup-hs/-/issues/197
+
 ## FAQ

-1. Why reimplement stack?
+### Why reimplement stack?

-ghcup is not a reimplementation of stack. The only common part is automatic installation of GHC, but even that differs in scope and design.
+GHCup is not a reimplementation of stack. The only common part is automatic installation of GHC,
+but even that differs in scope and design.

-2. Why not support windows?
+### Why should I use ghcup over stack?

-We do.
+GHCup is not a replacement for stack. Instead, it supports installing and managing stack versions.
+It does the same for cabal, GHC and HLS. As such, It doesn't make a workflow choice for you.

-3. Why the haskell reimplementation?
+### Why should I let ghcup manage stack?

-:-)
+You don't need to. However, some users seem to prefer to have a central tool that manages cabal and stack
+at the same time. Additionally, it can allow better sharing of GHC installation across these tools.
+Also see:
+
+* https://docs.haskellstack.org/en/stable/yaml_configuration/#system-ghc
+* https://github.com/commercialhaskell/stack/pull/5585
+
+### Why does ghcup not use stack code?
+
+Oddly, this question has been asked a couple of times. For the curious, here are a few reasons:
+
+1. GHCup started as a shell script. At the time of rewriting it in Haskell, the authors didn't even know that stack exposes *some* of its [installation API](https://hackage.haskell.org/package/stack-2.5.1.1/docs/Stack-Setup.html)
+2. Even if they did, it doesn't seem it would have satisfied their needs
+	  - it didn't support cabal installation, which was the main motivation behind GHCup back then
+	  - depending on a codebase as big as stack for a central part of one's application without having a short contribution pipeline would likely have caused stagnation or resulted in simply copy-pasting the relevant code in order to adjust it
+	  - it's not clear how GHCup would have been implemented with the provided API. It seems the codebases are fairly different. GHCup does a lot of symlink handling to expose a central `bin/` directory that users can easily put in PATH, without having to worry about anything more. It also provides explicit removal functionality, GHC cross-compilation, a TUI, etc etc.
+3. GHCup is built around unix principles and supposed to be simple.
+
+### Why not unify...
+
+#### ...stack and Cabal and do away with standalone installers
+
+GHCup is not involved in such decisions. cabal-install and stack might have a
+sufficiently different user experience to warrant having a choice.
+
+#### ...installer implementations and have a common library
+
+This sounds like an interesting goal. However, GHC installation isn't a hard engineering problem
+and the shared code wouldn't be too exciting. For such an effort to make sense, all involved
+parties would need to collaborate and have a short pipeline to get patches in.
+
+It's true this would solve the integration problem, but following unix principles, we can
+do similar via **hooks**. Both cabal and stack can support installation hooks. These hooks
+can then call into ghcup or anything else, also see:
+
+* https://github.com/haskell/cabal/issues/7394
+* https://github.com/commercialhaskell/stack/pull/5585
+
+#### ...installers (like, all of it)
+
+So far, there hasn't been an **open** discussion about this. Is this even a good idea?
+Sometimes projects converge eventually if their overlap is big enough, sometimes they don't.
+
+While unification sounds like a simplification of the ecosystem, it also takes away choice.
+Take `curl` and `wget` as an example.
+
+How bad do we need this?
+
+### Why not support windows?
+
+Windows is supported since GHCup version 0.1.15.1.
+
+### Why the haskell reimplementation?
+
+GHCup started as a portable posix shell script of maybe 50 LOC. GHC installation itself can be carried out in
+about ~3 lines of shell code (download, unpack , configure+make install). However, much convenient functionality
+has been added since, as well as ensuring that all operations are safe and correct. The shell script ended up with
+over 2k LOC, which was very hard to maintain.
+
+The main concern when switching from a portable shell script to haskell was platform/architecture support.
+However, ghcup now re-uses GHCs CI infrastructure and as such is perfectly in sync with all platforms that
+GHC supports.
+
+### Is GHCup affiliated with the Haskell Foundation?
+
+There has been some collaboration: Windows and Stack support were mainly requested by the Haskell Foundation
+and those seemed interesting features to add.
+
+Other than that, GHCup is dedicated only to its users and is supported by haskell.org through hosting and CI
+infrastructure.
--- a/app/ghcup-gen/Validate.hs
+++ b/app/ghcup-gen/Validate.hs
@@ -126,7 +126,7 @@ validate dls _ = do
        _ -> lift $ $(logWarn) [i|Linux Alpine missing for #{t} #{v'} #{arch'}|]

  checkUniqueTags tool = do
-    let allTags = join $ M.elems $ availableToolVersions dls tool
+    let allTags = join $ fmap _viTags $ M.elems $ availableToolVersions dls tool
    let nonUnique =
          fmap fst
            .   filter (\(_, b) -> not b)
@@ -164,7 +164,7 @@ validate dls _ = do

  -- a tool must have at least one of each mandatory tags
  checkMandatoryTags tool = do
-    let allTags = join $ M.elems $ availableToolVersions dls tool
+    let allTags = join $ fmap _viTags $ M.elems $ availableToolVersions dls tool
    forM_ [Latest, Recommended] $ \t -> case elem t allTags of
      False -> do
        lift $ $(logError) [i|Tag #{t} missing from #{tool}|]
@@ -174,7 +174,7 @@ validate dls _ = do
  -- all GHC versions must have a base tag
  checkGHCHasBaseVersion = do
    let allTags = M.toList $ availableToolVersions dls GHC
-    forM allTags $ \(ver, tags) -> case any isBase tags of
+    forM allTags $ \(ver, _viTags -> tags) -> case any isBase tags of
      False -> do
        lift $ $(logError) [i|Base tag missing from GHC ver #{ver}|]
        addError
@@ -237,7 +237,7 @@ validateTarballs (TarballFilter etool versionRegex) dls gt = do
                  ($(logError) $ T.pack $ prettyShow e)
                liftIO $ exitWith (ExitFailure 2)

-    let appstate = AppState (Settings True False Never Curl False GHCupURL False) dirs defaultKeyBindings (GHCupInfo mempty mempty mempty) pfreq
+    let appstate = AppState (Settings True False Never Curl True GHCupURL False) dirs defaultKeyBindings (GHCupInfo mempty mempty mempty) pfreq

    r <-
      runLogger
@@ -256,7 +256,7 @@ validateTarballs (TarballFilter etool versionRegex) dls gt = do
        case etool of
          Right (Just GHCup) -> do
            tmpUnpack <- lift mkGhcupTmpDir
-            _ <- liftE $ download dli tmpUnpack Nothing
+            _ <- liftE $ download (_dlUri dli) (Just (_dlHash dli)) tmpUnpack Nothing False
            pure Nothing
          Right _ -> do
            p <- liftE $ downloadCached dli Nothing
@@ -266,7 +266,7 @@ validateTarballs (TarballFilter etool versionRegex) dls gt = do
              $ p
          Left ShimGen -> do
            tmpUnpack <- lift mkGhcupTmpDir
-            _ <- liftE $ download dli tmpUnpack Nothing
+            _ <- liftE $ download (_dlUri dli) (Just (_dlHash dli)) tmpUnpack Nothing False
            pure Nothing
    case r of
      VRight (Just basePath) -> do
--- a/app/ghcup/BrickMain.hs
+++ b/app/ghcup/BrickMain.hs
@@ -59,7 +59,7 @@ import qualified Data.Vector                   as V


 hiddenTools :: [Tool]
-hiddenTools = [Stack]
+hiddenTools = []


 data BrickData = BrickData
@@ -440,27 +440,29 @@ install' _ (_, ListResult {..}) = do
              , TagNotFound
              , DigestError
              , DownloadFailed
+              , DirNotEmpty
              , NoUpdate
              , TarDirDoesNotExist
+              , FileAlreadyExistsError
              ]

  run (do
      case lTool of
        GHC   -> do
          let vi = getVersionInfo lVer GHC dls
-          liftE $ installGHCBin lVer $> vi
+          liftE $ installGHCBin lVer Nothing $> vi
        Cabal -> do
          let vi = getVersionInfo lVer Cabal dls
-          liftE $ installCabalBin lVer $> vi
+          liftE $ installCabalBin lVer Nothing $> vi
        GHCup -> do
          let vi = snd <$> getLatest dls GHCup
          liftE $ upgradeGHCup Nothing False $> vi
        HLS   -> do
          let vi = getVersionInfo lVer HLS dls
-          liftE $ installHLSBin lVer $> vi
+          liftE $ installHLSBin lVer Nothing $> vi
        Stack -> do
          let vi = getVersionInfo lVer Stack dls
-          liftE $ installStackBin lVer $> vi
+          liftE $ installStackBin lVer Nothing $> vi
    )
    >>= \case
          VRight vi                         -> do
--- a/app/ghcup/Main.hs
+++ b/app/ghcup/Main.hs
@@ -78,6 +78,8 @@ import qualified Data.Map.Strict               as M
 import qualified Data.Text                     as T
 import qualified Data.Text.IO                  as T
 import qualified Data.Text.Encoding            as E
+import qualified Data.Yaml                     as Y
+import qualified Data.Yaml.Pretty              as YP
 import qualified Text.Megaparsec               as MP
 import qualified Text.Megaparsec.Char          as MPC

@@ -105,6 +107,7 @@ data Command
  | Rm (Either RmCommand RmOptions)
  | DInfo
  | Compile CompileCommand
+  | Config ConfigCommand
  | Whereis WhereisOptions WhereisCommand
  | Upgrade UpgradeOpts Bool
  | ToolRequirements
@@ -138,6 +141,7 @@ data InstallOptions = InstallOptions
  , instPlatform :: Maybe PlatformRequest
  , instBindist  :: Maybe URI
  , instSet      :: Bool
+  , isolateDir   :: Maybe FilePath
  }

 data SetCommand = SetGHC SetOptions
@@ -173,6 +177,8 @@ data RmOptions = RmOptions

 data CompileCommand = CompileGHC GHCCompileOptions

+data ConfigCommand = ShowConfig | SetConfig String String | InitConfig
+
 data GHCCompileOptions = GHCCompileOptions
  { targetGhc    :: Either Version GitBranch
  , bootstrapGhc :: Either Version FilePath
@@ -185,6 +191,7 @@ data GHCCompileOptions = GHCCompileOptions
  , ovewrwiteVer :: Maybe Version
  , buildFlavour :: Maybe String
  , hadrian      :: Bool
+  , isolateDir   :: Maybe FilePath
  }

 data UpgradeOpts = UpgradeInplace
@@ -408,6 +415,12 @@ com =
                  <> footerDoc (Just $ text changeLogFooter)
                  )
               )
+          <> command
+               "config"
+               (   Config
+               <$> info (configP <**> helper)
+                        (progDesc "Show or set config" <> footerDoc (Just $ text configFooter))
+               )
          <> commandGroup "Other commands:"
          <> hidden
          )
@@ -482,6 +495,17 @@ Examples:
  ghcup prefetch ghc 8.10.5
  ghcup --offline install ghc 8.10.5|]

+configFooter :: String
+configFooter = [s|Examples:
+
+# show current config
+ghcup config
+
+# initialize config
+ghcup config init
+
+# set <key> <value> configuration pair
+ghcup config <key> <value>|]

 installCabalFooter :: String
 installCabalFooter = [s|Discussion:
@@ -574,7 +598,7 @@ Examples:

 installOpts :: Maybe Tool -> Parser InstallOptions
 installOpts tool =
-  (\p (u, v) b -> InstallOptions v p u b)
+  (\p (u, v) b is -> InstallOptions v p u b is)
    <$> optional
          (option
            (eitherReader platformParser)
@@ -603,6 +627,15 @@ installOpts tool =
          (long "set" <> help
            "Set as active version after install"
          )
+    <*> optional
+          (option
+           (eitherReader isolateParser)
+           (  short 'i'
+           <> long "isolate"
+           <> metavar "DIR"
+           <> help "install in an isolated dir instead of the default one"
+           )
+          )


 setParser :: Parser (Either SetCommand SetOptions)
@@ -786,6 +819,19 @@ Examples:
  # build cross compiler
  ghcup compile ghc -j 4 -v 8.4.2 -b 8.2.2 -x armv7-unknown-linux-gnueabihf --config $(pwd)/build.mk -- --enable-unregisterised|]

+configP :: Parser ConfigCommand
+configP = subparser
+      (  command "init" initP
+      <> command "set"  setP -- [set] KEY VALUE at help lhs
+      <> command "show" showP
+      )
+    <|> argsP -- add show for a single option
+    <|> pure ShowConfig
+ where
+  initP = info (pure InitConfig) (progDesc "Write default config to ~/.ghcup/config.yaml")
+  showP = info (pure ShowConfig) (progDesc "Show current config (default)")
+  setP  = info argsP (progDesc "Set config KEY to VALUE")
+  argsP = SetConfig <$> argument str (metavar "KEY") <*> argument str (metavar "VALUE")

 whereisP :: Parser WhereisCommand
 whereisP = subparser
@@ -1000,6 +1046,15 @@ ghcCompileOpts =
    <*> switch
          (long "hadrian" <> help "Use the hadrian build system instead of make (only git versions seem to be properly supported atm)"
          )
+    <*> optional
+          (option
+            (eitherReader isolateParser)
+            (  short 'i'
+            <> long "isolate"
+            <> metavar "DIR"
+            <> help "install in an isolated directory instead of the default one, no symlinks to this installation will be made"
+            )
+           )


 toolVersionParser :: Parser ToolVersion
@@ -1061,6 +1116,7 @@ tagCompleter tool add = listIOCompleter $ do
    VRight ghcupInfo -> do
      let allTags = filter (\t -> t /= Old)
            $ join
+            $ fmap _viTags
            $ M.elems
            $ availableToolVersions (_ghcupDownloads ghcupInfo) tool
      pure $ nub $ (add ++) $ fmap tagToString allTags
@@ -1214,6 +1270,10 @@ platformParser s' = case MP.parse (platformP <* MP.eof) "" (T.pack s') of
 bindistParser :: String -> Either String URI
 bindistParser = first show . parseURI strictURIParserOptions . UTF8.fromString

+isolateParser :: FilePath -> Either String FilePath
+isolateParser f = case isValid f of
+              True -> Right $ normalise f
+              False -> Left "Please enter a valid filepath for isolate dir."

 toSettings :: Options -> IO (Settings, KeyBindings)
 toSettings options = do
@@ -1257,6 +1317,21 @@ toSettings options = do
         , bShowAllTools = fromMaybe bShowAllTools kShowAllTools
         }

+updateSettings :: Monad m => UTF8.ByteString -> Settings -> Excepts '[JSONError] m Settings
+updateSettings config settings = do
+  settings' <- lE' JSONDecodeError . first show . Y.decodeEither' $ config
+  pure $ mergeConf settings' settings
+  where
+   mergeConf :: UserSettings -> Settings -> Settings
+   mergeConf UserSettings{..} Settings{..} =
+     let cache'      = fromMaybe cache uCache
+         noVerify'   = fromMaybe noVerify uNoVerify
+         keepDirs'   = fromMaybe keepDirs uKeepDirs
+         downloader' = fromMaybe downloader uDownloader
+         verbose'    = fromMaybe verbose uVerbose
+         urlSource'  = fromMaybe urlSource uUrlSource
+         noNetwork'  = fromMaybe noNetwork uNoNetwork
+     in Settings cache' noVerify' keepDirs' downloader' verbose' urlSource' noNetwork'

 upgradeOptsP :: Parser UpgradeOpts
 upgradeOptsP =
@@ -1291,6 +1366,11 @@ describe_result = $( LitE . StringL <$>
                     )
                   )

+formatConfig :: UserSettings -> String
+formatConfig settings
+  = UTF8.toString . YP.encodePretty yamlConfig $ settings
+ where
+  yamlConfig = YP.setConfCompare compare YP.defConfig

 main :: IO ()
 main = do
@@ -1390,9 +1470,18 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                race_ (liftIO $ runLogger $ flip runReaderT dirs $ cleanupTrash)
                      (threadDelay 5000000 >> runLogger ($(logWarn) [i|Killing cleanup thread (exceeded 5s timeout)... please remove leftover files in #{recycleDir} manually|]))

-                lookupEnv "GHCUP_SKIP_UPDATE_CHECK" >>= \case
-                  Nothing -> runLogger $ flip runReaderT s' $ checkForUpdates
-                  Just _ -> pure ()
+                case optCommand of
+                  Nuke -> pure ()
+                  Whereis _ _ -> pure ()
+                  DInfo -> pure ()
+                  ToolRequirements -> pure ()
+                  ChangeLog _ -> pure ()
+#if defined(BRICK)
+                  Interactive -> pure ()
+#endif
+                  _ -> lookupEnv "GHCUP_SKIP_UPDATE_CHECK" >>= \case
+                         Nothing -> runLogger $ flip runReaderT s' $ checkForUpdates
+                         Just _ -> pure ()

                -- TODO: always run for windows
                (siletRunLogger $ flip runReaderT s' $ runE ensureGlobalTools) >>= \case
@@ -1435,6 +1524,8 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
 #endif
                      , FileDoesNotExistError
                      , CopyError
+                      , NotInstalled
+                      , DirNotEmpty
                      , NoDownload
                      , NotInstalled
                      , BuildFailed
@@ -1444,6 +1535,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                      , TarDirDoesNotExist
                      , NextVerNotFound
                      , NoToolVersionSet
+                      , FileAlreadyExistsError
                      ]

          let runInstTool mInstPlatform action' = do
@@ -1545,6 +1637,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                      , UnknownArchive
                      , TarDirDoesNotExist
                      , NotInstalled
+                      , DirNotEmpty
 #if !defined(TAR)
                      , ArchiveResult
 #endif
@@ -1607,22 +1700,23 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
          -----------------------

          let installGHC InstallOptions{..} =
-                  (case instBindist of
-                     Nothing -> runInstTool instPlatform $ do
+                (case instBindist of
+                   Nothing -> runInstTool instPlatform $ do
+                     (v, vi) <- liftE $ fromVersion instVer GHC
+                     liftE $ installGHCBin (_tvVersion v) isolateDir
+                     when instSet $ void $ liftE $ setGHC v SetGHCOnly
+                     pure vi
+                   Just uri -> do
+                     s' <- liftIO appState
+                     runInstTool' s'{ settings = settings {noVerify = True}} instPlatform $ do
                       (v, vi) <- liftE $ fromVersion instVer GHC
-                       liftE $ installGHCBin (_tvVersion v)
+                       liftE $ installGHCBindist
+                         (DownloadInfo uri (Just $ RegexDir "ghc-.*") "")
+                         (_tvVersion v)
+                         isolateDir
                       when instSet $ void $ liftE $ setGHC v SetGHCOnly
                       pure vi
-                     Just uri -> do
-                       s' <- liftIO appState
-                       runInstTool' s'{ settings = settings {noVerify = True}} instPlatform $ do
-                         (v, vi) <- liftE $ fromVersion instVer GHC
-                         liftE $ installGHCBindist
-                           (DownloadInfo uri (Just $ RegexDir "ghc-.*") "")
-                           (_tvVersion v)
-                         when instSet $ void $ liftE $ setGHC v SetGHCOnly
-                         pure vi
-                    )
+                  )
                    >>= \case
                          VRight vi -> do
                            runLogger $ $(logInfo) "GHC installation successful"
@@ -1651,7 +1745,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                (case instBindist of
                   Nothing -> runInstTool instPlatform $ do
                     (v, vi) <- liftE $ fromVersion instVer Cabal
-                     liftE $ installCabalBin (_tvVersion v)
+                     liftE $ installCabalBin (_tvVersion v) isolateDir
                     pure vi
                   Just uri -> do
                     s' <- appState
@@ -1660,6 +1754,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                       liftE $ installCabalBindist
                           (DownloadInfo uri Nothing "")
                           (_tvVersion v)
+                           isolateDir
                       pure vi
                  )
                  >>= \case
@@ -1679,10 +1774,10 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                          pure $ ExitFailure 4

          let installHLS InstallOptions{..} =
-                (case instBindist of
+                 (case instBindist of
                   Nothing -> runInstTool instPlatform $ do
                     (v, vi) <- liftE $ fromVersion instVer HLS
-                     liftE $ installHLSBin (_tvVersion v)
+                     liftE $ installHLSBin (_tvVersion v) isolateDir
                     pure vi
                   Just uri -> do
                     s' <- appState
@@ -1691,6 +1786,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                       liftE $ installHLSBindist
                           (DownloadInfo uri Nothing "")
                           (_tvVersion v)
+                           isolateDir
                       pure vi
                  )
                  >>= \case
@@ -1710,19 +1806,20 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                          pure $ ExitFailure 4

          let installStack InstallOptions{..} =
-                (case instBindist of
-                   Nothing -> runInstTool instPlatform $ do
-                     (v, vi) <- liftE $ fromVersion instVer Stack
-                     liftE $ installStackBin (_tvVersion v)
-                     pure vi
-                   Just uri -> do
-                     s' <- appState
-                     runInstTool' s'{ settings = settings { noVerify = True}} instPlatform $ do
-                       (v, vi) <- liftE $ fromVersion instVer Stack
-                       liftE $ installStackBindist
-                           (DownloadInfo uri Nothing "")
-                           (_tvVersion v)
-                       pure vi
+                 (case instBindist of
+                    Nothing -> runInstTool instPlatform $ do
+                      (v, vi) <- liftE $ fromVersion instVer Stack
+                      liftE $ installStackBin (_tvVersion v) isolateDir
+                      pure vi
+                    Just uri -> do
+                      s' <- appState
+                      runInstTool' s'{ settings = settings { noVerify = True}} instPlatform $ do
+                        (v, vi) <- liftE $ fromVersion instVer Stack
+                        liftE $ installStackBindist
+                            (DownloadInfo uri Nothing "")
+                            (_tvVersion v)
+                            isolateDir
+                        pure vi
                  )
                  >>= \case
                        VRight vi -> do
@@ -1951,6 +2048,7 @@ Report bugs at <https://gitlab.haskell.org/haskell/ghcup-hs/issues>|]
                            addConfArgs
                            buildFlavour
                            hadrian
+                            isolateDir
                GHCupInfo { _ghcupDownloads = dls } <- lift getGHCupInfo
                let vi = getVersionInfo (_tvVersion targetVer) GHC dls
                when setCompile $ void $ liftE $
@@ -1980,6 +2078,37 @@ Make sure to clean up #{tmpdir} afterwards.|])
                        runLogger $ $(logError) $ T.pack $ prettyShow e
                        pure $ ExitFailure 9

+            Config InitConfig -> do
+              path <- getConfigFilePath
+              writeFile path $ formatConfig $ fromSettings settings (Just keybindings)
+              runLogger $ $(logDebug) [i|"config.yaml initialized at #{path}|]
+              pure ExitSuccess
+
+            Config ShowConfig -> do
+              putStrLn $ formatConfig $ fromSettings settings (Just keybindings)
+              pure ExitSuccess
+
+            Config (SetConfig k v) -> do
+              case v of
+                "" -> do
+                  runLogger $ $(logError) "Empty values are not allowed"
+                  pure $ ExitFailure 55
+                _  -> do
+                  r <- runE @'[JSONError] $ do
+                    settings' <- updateSettings [i|#{k}: #{v}\n|] settings
+                    path <- liftIO getConfigFilePath
+                    liftIO $ writeFile path $ formatConfig $ fromSettings settings' (Just keybindings)
+                    runLogger $ $(logDebug) $ T.pack $ show settings'
+                    pure ()
+
+                  case r of
+                      VRight _ -> pure ExitSuccess
+                      VLeft (V (JSONDecodeError e)) -> do
+                        runLogger $ $(logError)
+                          [i|Error decoding config: #{e}|]
+                        pure $ ExitFailure 65
+                      VLeft _ -> pure $ ExitFailure 65
+
            Whereis WhereisOptions{..} (WhereisTool tool (Just (ToolVersion v))) ->
              runLeanWhereIs (do
                loc <- liftE $ whereIsTool tool v
@@ -2017,22 +2146,25 @@ Make sure to clean up #{tmpdir} afterwards.|])
                (UpgradeAt p)   -> pure $ Just p
                UpgradeGHCupDir -> pure (Just (binDir </> "ghcup" <> exeExt))

-              runUpgrade (liftE $ upgradeGHCup target force') >>= \case
-                VRight v' -> do
-                  GHCupInfo { _ghcupDownloads = dls } <- runAppState getGHCupInfo
-                  let pretty_v = prettyVer v'
-                  let vi = fromJust $ snd <$> getLatest dls GHCup
-                  runLogger $ $(logInfo)
-                    [i|Successfully upgraded GHCup to version #{pretty_v}|]
-                  forM_ (_viPostInstall vi) $ \msg ->
-                    runLogger $ $(logInfo) msg
-                  pure ExitSuccess
-                VLeft (V NoUpdate) -> do
-                  runLogger $ $(logWarn) [i|No GHCup update available|]
-                  pure ExitSuccess
-                VLeft e -> do
-                  runLogger $ $(logError) $ T.pack $ prettyShow e
-                  pure $ ExitFailure 11
+              runUpgrade (do
+                v' <- liftE $ upgradeGHCup target force'
+                GHCupInfo { _ghcupDownloads = dls } <- lift getGHCupInfo
+                pure (v', dls)
+                ) >>= \case
+                  VRight (v', dls) -> do
+                    let pretty_v = prettyVer v'
+                    let vi = fromJust $ snd <$> getLatest dls GHCup
+                    runLogger $ $(logInfo)
+                      [i|Successfully upgraded GHCup to version #{pretty_v}|]
+                    forM_ (_viPostInstall vi) $ \msg ->
+                      runLogger $ $(logInfo) msg
+                    pure ExitSuccess
+                  VLeft (V NoUpdate) -> do
+                    runLogger $ $(logWarn) [i|No GHCup update available|]
+                    pure ExitSuccess
+                  VLeft e -> do
+                    runLogger $ $(logError) $ T.pack $ prettyShow e
+                    pure $ ExitFailure 11

            ToolRequirements -> do
              s' <- appState
@@ -2116,7 +2248,7 @@ Make sure to clean up #{tmpdir} afterwards.|])
                                  runLogger $ $logInfo "Nuclear Annihilation complete!"
                                  pure ExitSuccess
                              | otherwise -> do
-                                  runLogger $ $logWarn "These Files have survived Nuclear Annihilation, you may remove them manually."
+                                  runLogger $ $logError "These Files have survived Nuclear Annihilation, you may remove them manually."
                                  forM_ leftOverFiles putStrLn
                                  pure ExitSuccess

--- a/4
+++ b/4
@@ -20,7 +20,7 @@

 plat="$(uname -s)"
 arch=$(uname -m)
-ghver="0.1.15.2"
+ghver="0.1.16.2"
 base_url="https://downloads.haskell.org/~ghcup"

 export GHCUP_SKIP_UPDATE_CHECK=yes
@@ -275,6 +275,8 @@ find_shell() {
 ask_bashrc() {
 	if [ -n "${BOOTSTRAP_HASKELL_ADJUST_BASHRC}" ] ; then
 		return 1
+	elif [ -z "${MY_SHELL}" ] ; then
+		return 0
 	fi

 	while true; do
--- a/bootstrap-haskell.ps1
+++ b/bootstrap-haskell.ps1
@@ -158,6 +158,26 @@ $ErrorActionPreference = 'Stop'

 $GhcupBasePrefixEnv = [System.Environment]::GetEnvironmentVariable('GHCUP_INSTALL_BASE_PREFIX', 'user')

+if (Get-Command -Name 'chocolatey.exe' -ErrorAction SilentlyContinue) {
+  if (!($Silent)) {
+    Print-Msg -color Magenta -msg (@'
+Chocolatey was detected on your system. It is capable of installing the Haskell toolchain as well.
+If you want to rather use that instead of ghcup, abort the installation and run the following at an
+elevated command prompt:
+    choco install haskell-dev
+    refreshenv
+
+'@)
+    $decision = $Host.UI.PromptForChoice(''
+    , 'Continue with GHCup installation?'
+    , [System.Management.Automation.Host.ChoiceDescription[]] @('&Continue'
+        '&Abort'), 0)
+    if ($decision -eq 1) {
+      Exit 0
+    }
+  }
+}
+
 if ($GhcupBasePrefixEnv) {
  $defaultGhcupBasePrefix = $GhcupBasePrefixEnv
 } else {
@@ -276,7 +296,7 @@ if ($CabalDir) {
  while ($true) {

    $defaultCabalDir = ('{0}\cabal' -f $GhcupBasePrefix)
-    Print-Msg -color Magenta -msg ('Specify Cabal directory (this is where haskell packages end up). Press enter to accept the default [{0}]:' -f $defaultCabalDir)
+    Print-Msg -color Magenta -msg ('Specify Cabal directory (this is where haskell packages end up){1}Press enter to accept the default [{0}]:' -f $defaultCabalDir, "`n")
    $CabalDirPrompt = Read-Host
    $CabDirEnv = ($defaultCabalDir,$CabalDirPrompt)[[bool]$CabalDirPrompt]

@@ -371,7 +391,7 @@ if (!(Test-Path -Path ('{0}' -f $MsysDir))) {
    Exec "$Bash" '-lc' 'pacman --noconfirm -Syuu'

    Print-Msg -msg 'Installing Dependencies...'
-    Exec "$Bash" '-lc' 'pacman --noconfirm -S --needed curl mingw-w64-x86_64-pkgconf'
+    Exec "$Bash" '-lc' 'pacman --noconfirm -S --needed curl autoconf mingw-w64-x86_64-pkgconf'

    Print-Msg -msg 'Updating SSL root certificate authorities...'
    Exec "$Bash" '-lc' 'pacman --noconfirm -S ca-certificates'
@@ -383,7 +403,7 @@ if (!(Test-Path -Path ('{0}' -f $MsysDir))) {
    while ($true) {
      if ($GhcupMsys2) {
        $defaultMsys2Dir = $GhcupMsys2
-        Print-Msg -color Magenta -msg ('Input existing MSys2 toolchain directory. Press enter to accept the default [{0}]:' -f $defaultMsys2Dir)
+        Print-Msg -color Magenta -msg ('Input existing MSys2 toolchain directory.{1}Press enter to accept the default [{0}]:' -f $defaultMsys2Dir, "`n")
        $MsysDirPrompt = Read-Host
        $MsysDir = ($defaultMsys2Dir,$MsysDirPrompt)[[bool]$MsysDirPrompt]
      } else {
@@ -412,11 +432,74 @@ if (!(Test-Path -Path ('{0}' -f $MsysDir))) {
 }

 Print-Msg -msg 'Creating shortcuts...'
+$uninstallShortCut = @'
+$decision = $Host.UI.PromptForChoice('Uninstall Haskell'
+, 'Do you want to uninstall all of the haskell toolchain, including GHC, Cabal, Stack and GHCup itself?'
+, [System.Management.Automation.Host.ChoiceDescription[]] @('&Uninstall'
+    '&Abort'), 0)
+
+if ($decision -eq 1) {
+  Exit 0
+}
+
+Write-Host 'Removing ghcup toolchain' -ForegroundColor Green
+ghcup nuke
+
+Write-Host 'Unsetting GHCUP_INSTALL_BASE_PREFIX' -ForegroundColor Green
+[Environment]::SetEnvironmentVariable('GHCUP_INSTALL_BASE_PREFIX', $null, [System.EnvironmentVariableTarget]::User)
+
+$ghcupMsys2 = [System.Environment]::GetEnvironmentVariable('GHCUP_MSYS2', 'user')
+$GhcupBasePrefixEnv = [System.Environment]::GetEnvironmentVariable('GHCUP_INSTALL_BASE_PREFIX', 'user')
+
+if ($ghcupMsys2) {
+  $msys2Dir = [IO.Path]::GetFullPath($ghcupMsys2)
+  $baseDir = [IO.Path]::GetFullPath('{0}\ghcup' -f $GhcupBasePrefixEnv)
+
+  if ($msys2Dir.StartsWith($baseDir)) {
+    Write-Host 'Unsetting GHCUP_MSYS2' -ForegroundColor Green
+    [Environment]::SetEnvironmentVariable('GHCUP_MSYS2', $null, [System.EnvironmentVariableTarget]::User)
+  } else {
+    Write-Host ('GHCUP_MSYS2 env variable is set to a non-standard location {0}. Environment variable not unset. Uninstall manually.' -f $msys2Dir) -ForegroundColor Magenta
+  }
+} else {
+  Write-Host 'Unsetting GHCUP_MSYS2' -ForegroundColor Green
+  [Environment]::SetEnvironmentVariable('GHCUP_MSYS2', $null, [System.EnvironmentVariableTarget]::User)
+}
+
+Write-Host 'Removing ghcup from PATH env var' -ForegroundColor Green
+$path = [System.Environment]::GetEnvironmentVariable(
+    'PATH',
+    'user'
+)
+$path = ($path.Split(';') | Where-Object { $_ -ne ('{0}\bin' -f $baseDir) }) -join ';'
+[System.Environment]::SetEnvironmentVariable(
+    'PATH',
+    $path,
+    'user'
+)
+
+Write-Host 'Removing desktop files' -ForegroundColor Green
+$DesktopDir = [Environment]::GetFolderPath("Desktop")
+Remove-Item -LiteralPath ('{0}\Install GHC dev dependencies.lnk' -f $DesktopDir) -Force
+Remove-Item -LiteralPath ('{0}\Mingw haskell shell.lnk' -f $DesktopDir) -Force
+Remove-Item -LiteralPath ('{0}\Mingw package management docs.url' -f $DesktopDir) -Force
+
+Write-Host ('CABAL_DIR env variable is still set to {0} and will be used by cabal regardless of ghcup. You may want to uninstall this manually.' -f [System.Environment]::GetEnvironmentVariable('CABAL_DIR', 'user')) -ForegroundColor Magenta
+Write-Host 'You may remove this script now.' -ForegroundColor Magenta
+
+if ($Host.Name -eq "ConsoleHost")
+{
+    Write-Host "Press any key to continue..."
+    $Host.UI.RawUI.ReadKey("NoEcho,IncludeKeyUp") > $null
+}
+'@
+
 $DesktopDir = [Environment]::GetFolderPath("Desktop")
 $GhcInstArgs = '-mingw64 -mintty -c "pacman --noconfirm -S --needed base-devel gettext autoconf make libtool automake python p7zip patch unzip"'
 Create-Shortcut -SourceExe ('{0}\msys2_shell.cmd' -f $MsysDir) -ArgumentsToSourceExe $GhcInstArgs -DestinationPath ('{0}\Install GHC dev dependencies.lnk' -f $DesktopDir)
 Create-Shortcut -SourceExe ('{0}\msys2_shell.cmd' -f $MsysDir) -ArgumentsToSourceExe '-mingw64' -DestinationPath ('{0}\Mingw haskell shell.lnk' -f $DesktopDir)
 Create-Shortcut -SourceExe 'https://www.msys2.org/docs/package-management' -ArgumentsToSourceExe '' -DestinationPath ('{0}\Mingw package management docs.url' -f $DesktopDir)
+$null = New-Item -Path $DesktopDir -Name "Uninstall Haskell.ps1" -ItemType "file" -Force -Value $uninstallShortCut

 Print-Msg -msg ('Adding {0}\bin to Users Path...' -f $GhcupDir)
 Add-EnvPath -Path ('{0}\bin' -f ([System.IO.Path]::GetFullPath("$GhcupDir"))) -Container 'User'
--- a/cabal.ghc8105.project
+++ b/cabal.ghc8105.project
@@ -8,6 +8,11 @@ package ghcup
    tests: True
    flags: +tui

+source-repository-package
+    type: git
+    location: https://github.com/jtdaugherty/brick.git
+    tag: b3b96cfe66dfd398d338e3feb2b6855e66a35190
+
 source-repository-package
    type: git
    location: https://github.com/Bodigrim/tar
--- a/cabal.ghc8105.project.freeze
+++ b/cabal.ghc8105.project.freeze
@@ -5,7 +5,7 @@ constraints: any.Cabal ==3.2.1.0,
             HsOpenSSL -fast-bignum -homebrew-openssl -macports-openssl -use-pkg-config,
             any.QuickCheck ==2.14.2,
             QuickCheck -old-random +templatehaskell,
-             any.StateVar ==1.2.1,
+             any.StateVar ==1.2.2,
             any.aeson ==1.5.6.0,
             aeson -bytestring-builder -cffi -developer -fast,
             any.aeson-pretty ==0.8.8,
@@ -34,7 +34,7 @@ constraints: any.Cabal ==3.2.1.0,
             any.binary ==0.8.8.0,
             any.bindings-DSL ==1.0.25,
             any.blaze-builder ==0.4.2.1,
-             any.brick ==0.61,
+             any.brick ==0.63,
             brick -demos,
             any.bytestring ==0.10.12.0,
             any.bz2 ==1.0.1.0,
@@ -66,7 +66,7 @@ constraints: any.Cabal ==3.2.1.0,
             any.config-ini ==0.2.4.0,
             config-ini -enable-doctests,
             any.containers ==0.6.4.1,
-             any.contravariant ==1.5.3,
+             any.contravariant ==1.5.4,
             contravariant +semigroups +statevar +tagged,
             any.cpphs ==1.20.9.1,
             cpphs -old-locale,
@@ -111,7 +111,7 @@ constraints: any.Cabal ==3.2.1.0,
             hsc2hs -in-ghc-tree,
             any.hspec ==2.7.10,
             any.hspec-core ==2.7.10,
-             any.hspec-discover ==2.7.10,
+             any.hspec-discover ==2.7.10 || ==2.8.2,
             any.hspec-expectations ==0.8.2,
             any.hspec-golden-aeson ==0.9.0.0,
             any.http-io-streams ==0.1.6.0,
@@ -137,7 +137,7 @@ constraints: any.Cabal ==3.2.1.0,
             any.microlens ==0.4.12.0,
             any.microlens-mtl ==0.2.0.1,
             any.microlens-th ==0.4.3.10,
-             any.monad-control ==1.0.2.3,
+             any.monad-control ==1.0.3,
             any.monad-logger ==0.3.36,
             monad-logger +template_haskell,
             any.monad-loops ==0.4.3,
@@ -176,7 +176,7 @@ constraints: any.Cabal ==3.2.1.0,
             any.recursion-schemes ==5.2.2.1,
             recursion-schemes +template-haskell,
             any.regex-base ==0.94.0.1,
-             any.regex-posix ==0.96.0.0,
+             any.regex-posix ==0.96.0.1,
             regex-posix -_regex-posix-clib,
             any.resourcet ==1.2.4.2,
             any.rts ==1.0.1,
@@ -228,7 +228,7 @@ constraints: any.Cabal ==3.2.1.0,
             any.transformers ==0.5.6.2,
             any.transformers-base ==0.4.5.2,
             transformers-base +orphaninstances,
-             any.transformers-compat ==0.6.6,
+             any.transformers-compat ==0.7,
             transformers-compat -five +five-three -four +generic-deriving +mtl -three -two,
             any.typed-process ==0.2.6.0,
             any.unix ==2.7.2.2,
@@ -261,4 +261,4 @@ constraints: any.Cabal ==3.2.1.0,
             any.zlib-bindings ==0.1.1.5,
             any.zstd ==0.1.2.0,
             zstd +standalone
-index-state: hackage.haskell.org 2021-07-12T18:00:24Z
+index-state: hackage.haskell.org 2021-07-27T07:59:57Z
--- a/cabal.ghc901.project
+++ b/cabal.ghc901.project
@@ -8,6 +8,11 @@ package ghcup
    tests: True
    flags: +tui

+source-repository-package
+    type: git
+    location: https://github.com/jtdaugherty/brick.git
+    tag: b3b96cfe66dfd398d338e3feb2b6855e66a35190
+
 source-repository-package
    type: git
    location: https://github.com/Bodigrim/tar
--- a/cabal.ghc901.project.freeze
+++ b/cabal.ghc901.project.freeze
@@ -5,7 +5,7 @@ constraints: any.Cabal ==3.4.0.0,
             HsOpenSSL -fast-bignum -homebrew-openssl -macports-openssl -use-pkg-config,
             any.QuickCheck ==2.14.2,
             QuickCheck -old-random +templatehaskell,
-             any.StateVar ==1.2.1,
+             any.StateVar ==1.2.2,
             any.aeson ==1.5.6.0,
             aeson -bytestring-builder -cffi -developer -fast,
             any.aeson-pretty ==0.8.8,
@@ -34,7 +34,7 @@ constraints: any.Cabal ==3.4.0.0,
             any.binary ==0.8.8.0,
             any.bindings-DSL ==1.0.25,
             any.blaze-builder ==0.4.2.1,
-             any.brick ==0.61,
+             any.brick ==0.63,
             brick -demos,
             any.bytestring ==0.10.12.1,
             any.bz2 ==1.0.1.0,
@@ -66,7 +66,7 @@ constraints: any.Cabal ==3.4.0.0,
             any.config-ini ==0.2.4.0,
             config-ini -enable-doctests,
             any.containers ==0.6.4.1,
-             any.contravariant ==1.5.3,
+             any.contravariant ==1.5.4,
             contravariant +semigroups +statevar +tagged,
             any.cpphs ==1.20.9.1,
             cpphs -old-locale,
@@ -112,7 +112,7 @@ constraints: any.Cabal ==3.4.0.0,
             hsc2hs -in-ghc-tree,
             any.hspec ==2.7.10,
             any.hspec-core ==2.7.10,
-             any.hspec-discover ==2.7.10,
+             any.hspec-discover ==2.7.10 || ==2.8.2,
             any.hspec-expectations ==0.8.2,
             any.hspec-golden-aeson ==0.9.0.0,
             any.http-io-streams ==0.1.6.0,
@@ -137,7 +137,7 @@ constraints: any.Cabal ==3.4.0.0,
             any.microlens ==0.4.12.0,
             any.microlens-mtl ==0.2.0.1,
             any.microlens-th ==0.4.3.10,
-             any.monad-control ==1.0.2.3,
+             any.monad-control ==1.0.3,
             any.monad-logger ==0.3.36,
             monad-logger +template_haskell,
             any.monad-loops ==0.4.3,
@@ -176,7 +176,7 @@ constraints: any.Cabal ==3.4.0.0,
             any.recursion-schemes ==5.2.2.1,
             recursion-schemes +template-haskell,
             any.regex-base ==0.94.0.1,
-             any.regex-posix ==0.96.0.0,
+             any.regex-posix ==0.96.0.1,
             regex-posix -_regex-posix-clib,
             any.resourcet ==1.2.4.2,
             any.rts ==1.0,
@@ -228,7 +228,7 @@ constraints: any.Cabal ==3.4.0.0,
             any.transformers ==0.5.6.2,
             any.transformers-base ==0.4.5.2,
             transformers-base +orphaninstances,
-             any.transformers-compat ==0.6.6,
+             any.transformers-compat ==0.7,
             transformers-compat -five +five-three -four +generic-deriving +mtl -three -two,
             any.typed-process ==0.2.6.0,
             any.unix ==2.7.2.2,
@@ -261,4 +261,4 @@ constraints: any.Cabal ==3.4.0.0,
             any.zlib-bindings ==0.1.1.5,
             any.zstd ==0.1.2.0,
             zstd +standalone
-index-state: hackage.haskell.org 2021-07-12T18:00:24Z
+index-state: hackage.haskell.org 2021-07-27T07:59:57Z
--- a/ghcup-0.0.1.json
+++ b/ghcup-0.0.1.json
--- a/ghcup-0.0.2.json
+++ b/ghcup-0.0.2.json
--- a/ghcup-0.0.2.yaml
+++ b/ghcup-0.0.2.yaml
@@ -1384,7 +1384,7 @@ ghcupDownloads:
              dlUri: https://oleg.fi/cabal-install-3.4.0.0-rc4/cabal-install-3.4.0.0-x86_64-freebsd-12.1-release.tar.xz
              dlHash: 9705e16d03497b46be4ad477e6c64d10890af853eafa8a9adf6dba89aa9e05f7
  GHCup:
-    0.1.14:
+    0.1.16.2:
      viTags:
      - Recommended
      - Latest
@@ -1394,22 +1394,22 @@ ghcupDownloads:
        A_64:
          Linux_UnknownLinux:
            unknown_versioning: &ghcup-64
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.14/x86_64-linux-ghcup-0.1.14
-              dlHash: e9b314d248f4d4604ce64cee1be7161c77c8940efd11986c9205779ec3b598dd
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-linux-ghcup-0.1.16.2
+              dlHash: d5e43b95ce1d42263376e414f7eb7c5dd440271c7c6cd9bad446fdeff3823893
          Darwin:
            unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.14/x86_64-apple-darwin-ghcup-0.1.14
-              dlHash: 69ede9db36c0ae631b679fceb87dd856d4753ee26f33610da37dd7a694809919
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-apple-darwin-ghcup-0.1.16.2
+              dlHash: a334620ccce7705211b2142882dde544003e6030af4b91a44c890542a90f879f
          FreeBSD:
            unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.14/x86_64-portbld-freebsd-ghcup-0.1.14
-              dlHash: 68b09404cf49061da539463f42f8ad67c9cef5c5d3f68a3c7c4f6760e8442bb9
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-portbld-freebsd-ghcup-0.1.16.2
+              dlHash: 92359592a5694375e53b22628920086bf4bbf0faff5be018a0ed3e745a6426a9
          Linux_Alpine:
            unknown_versioning: *ghcup-64
        A_32:
          Linux_UnknownLinux:
            unknown_versioning: &ghcup-32
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.14/i386-linux-ghcup-0.1.14
-              dlHash: ecb1157f010d2421764c52ab0cdbbf9a5c3da555827172c7b904d5f3f96c80fa
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/i386-linux-ghcup-0.1.16.2
+              dlHash: 01968ca6decac7b6e8ba6e2c817870d3fa47289a6507e0c1ab563f7b6eec0e38
          Linux_Alpine:
            unknown_versioning: *ghcup-32
--- a/ghcup-0.0.3.yaml
+++ b/ghcup-0.0.3.yaml
@@ -1451,7 +1451,7 @@ ghcupDownloads:
              dlUri: https://oleg.fi/cabal-install-3.4.0.0-rc4/cabal-install-3.4.0.0-x86_64-freebsd-12.1-release.tar.xz
              dlHash: 9705e16d03497b46be4ad477e6c64d10890af853eafa8a9adf6dba89aa9e05f7
  GHCup:
-    0.1.14:
+    0.1.16.2:
      viTags:
      - Recommended
      - Latest
@@ -1461,23 +1461,23 @@ ghcupDownloads:
        A_64:
          Linux_UnknownLinux:
            unknown_versioning: &ghcup-64
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.14/x86_64-linux-ghcup-0.1.14
-              dlHash: e9b314d248f4d4604ce64cee1be7161c77c8940efd11986c9205779ec3b598dd
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-linux-ghcup-0.1.16.2
+              dlHash: d5e43b95ce1d42263376e414f7eb7c5dd440271c7c6cd9bad446fdeff3823893
          Darwin:
            unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.14/x86_64-apple-darwin-ghcup-0.1.14
-              dlHash: 69ede9db36c0ae631b679fceb87dd856d4753ee26f33610da37dd7a694809919
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-apple-darwin-ghcup-0.1.16.2
+              dlHash: a334620ccce7705211b2142882dde544003e6030af4b91a44c890542a90f879f
          FreeBSD:
            unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.14/x86_64-portbld-freebsd-ghcup-0.1.14
-              dlHash: 68b09404cf49061da539463f42f8ad67c9cef5c5d3f68a3c7c4f6760e8442bb9
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-portbld-freebsd-ghcup-0.1.16.2
+              dlHash: 92359592a5694375e53b22628920086bf4bbf0faff5be018a0ed3e745a6426a9
          Linux_Alpine:
            unknown_versioning: *ghcup-64
        A_32:
          Linux_UnknownLinux:
            unknown_versioning: &ghcup-32
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.14/i386-linux-ghcup-0.1.14
-              dlHash: ecb1157f010d2421764c52ab0cdbbf9a5c3da555827172c7b904d5f3f96c80fa
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/i386-linux-ghcup-0.1.16.2
+              dlHash: 01968ca6decac7b6e8ba6e2c817870d3fa47289a6507e0c1ab563f7b6eec0e38
          Linux_Alpine:
            unknown_versioning: *ghcup-32
  HLS:
--- a/ghcup-0.0.4.yaml
+++ b/ghcup-0.0.4.yaml
@@ -1868,7 +1868,7 @@ ghcupDownloads:
              dlUri: https://downloads.haskell.org/~ghcup/unofficial-bindists/cabal/3.4.0.0/cabal-install-3.4.0.0-armv7-linux-bootstrapped.tar.xz
              dlHash: 16c0d1eaba24bed14f3e152970179a45d9f9bb5cc839b2c210ad06eb7d4826ed
  GHCup:
-    0.1.15.2:
+    0.1.16.2:
      viTags:
      - Recommended
      - Latest
@@ -1878,39 +1878,39 @@ ghcupDownloads:
        A_64:
          Linux_UnknownLinux:
            unknown_versioning: &ghcup-64
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.15.2/x86_64-linux-ghcup-0.1.15.2
-              dlHash: 1eb1bb318a327754f42eaa2245bc81fe53be7c791160d28a186893ded3004ed7
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-linux-ghcup-0.1.16.2
+              dlHash: d5e43b95ce1d42263376e414f7eb7c5dd440271c7c6cd9bad446fdeff3823893
          Darwin:
            unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.15.2/x86_64-apple-darwin-ghcup-0.1.15.2
-              dlHash: c2a6436a49f19f108493954d4a3efcb27503e343dd6288c2641784d32320b1ea
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-apple-darwin-ghcup-0.1.16.2
+              dlHash: a334620ccce7705211b2142882dde544003e6030af4b91a44c890542a90f879f
          FreeBSD:
            unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.15.2/x86_64-portbld-freebsd-ghcup-0.1.15.2
-              dlHash: 7e0c17dd78ebd9fd03e6ecea278c192bac31ca333721bde5b0ef99438b847a20
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-portbld-freebsd-ghcup-0.1.16.2
+              dlHash: 92359592a5694375e53b22628920086bf4bbf0faff5be018a0ed3e745a6426a9
          Linux_Alpine:
            unknown_versioning: *ghcup-64
        A_32:
          Linux_UnknownLinux:
            unknown_versioning: &ghcup-32
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.15.2/i386-linux-ghcup-0.1.15.2
-              dlHash: 3b1fe710cded0398e920ec9716089ba65226abf181741897f387e7c539a619c2
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/i386-linux-ghcup-0.1.16.2
+              dlHash: 01968ca6decac7b6e8ba6e2c817870d3fa47289a6507e0c1ab563f7b6eec0e38
          Linux_Alpine:
            unknown_versioning: *ghcup-32
        A_ARM64:
          Linux_UnknownLinux:
            unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.15.2/aarch64-linux-ghcup-0.1.15.2
-              dlHash: d91b7a5416f292f2cf813824eb419f76ad9976d258cee3581123cb6eb01db9a7
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/aarch64-linux-ghcup-0.1.16.2
+              dlHash: 0bdbfc724e0ddabb266156eea83c2c4e19c6ed79dd06db0c29b7d69df8d9fa8c
          Darwin:
            unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.15.2/aarch64-apple-darwin-ghcup-0.1.15.2
-              dlHash: 20625ba5e7488f2a6155331750ecead3815ea16b2695c20521633c1412f012cc
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/aarch64-apple-darwin-ghcup-0.1.16.2
+              dlHash: 8854e991a2ba1350abda59dab96ce50ae7729d1ce99399d67929ef31e90f1da5
        A_ARM:
          Linux_UnknownLinux:
            unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.15.2/armv7-linux-ghcup-0.1.15.2
-              dlHash: 03a4af5ed895ada1dd21f4cc3f64dc9078a5bf4268313021d004c04bea7f9c2e
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/armv7-linux-ghcup-0.1.16.2
+              dlHash: 983ebb5b584bfa600704216a63f94b40d36a02573834e90ef1042c8472d9ad57
  HLS:
    1.1.0:
      viTags:
--- a/ghcup-0.0.5.yaml
+++ b/ghcup-0.0.5.yaml
@@ -96,6 +96,7 @@ toolRequirements:
      Linux_Alpine:
        unknown_versioning:
          distroPKGs:
+          - binutils-gold
          - curl
          - gcc
          - g++
@@ -2024,7 +2025,7 @@ ghcupDownloads:
              dlUri: https://downloads.haskell.org/~ghcup/unofficial-bindists/cabal/3.4.0.0/cabal-install-3.4.0.0-armv7-linux-bootstrapped.tar.xz
              dlHash: 16c0d1eaba24bed14f3e152970179a45d9f9bb5cc839b2c210ad06eb7d4826ed
  GHCup:
-    0.1.15.2:
+    0.1.16.2:
      viTags:
      - Recommended
      - Latest
@@ -2034,52 +2035,55 @@ ghcupDownloads:
        A_64:
          Linux_UnknownLinux:
            unknown_versioning: &ghcup-64
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.15.2/x86_64-linux-ghcup-0.1.15.2
-              dlHash: 1eb1bb318a327754f42eaa2245bc81fe53be7c791160d28a186893ded3004ed7
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-linux-ghcup-0.1.16.2
+              dlHash: d5e43b95ce1d42263376e414f7eb7c5dd440271c7c6cd9bad446fdeff3823893
          Darwin:
            unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.15.2/x86_64-apple-darwin-ghcup-0.1.15.2
-              dlHash: c2a6436a49f19f108493954d4a3efcb27503e343dd6288c2641784d32320b1ea
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-apple-darwin-ghcup-0.1.16.2
+              dlHash: a334620ccce7705211b2142882dde544003e6030af4b91a44c890542a90f879f
          FreeBSD:
            unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.15.2/x86_64-portbld-freebsd-ghcup-0.1.15.2
-              dlHash: 7e0c17dd78ebd9fd03e6ecea278c192bac31ca333721bde5b0ef99438b847a20
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-portbld-freebsd-ghcup-0.1.16.2
+              dlHash: 92359592a5694375e53b22628920086bf4bbf0faff5be018a0ed3e745a6426a9
          Windows:
            unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.15.2/x86_64-mingw64-ghcup-0.1.15.2.exe
-              dlHash: 4d832052754379531ac472aeef35666e433acfee79d4079826b8ede8ca5de520
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/x86_64-mingw64-ghcup-0.1.16.2.exe
+              dlHash: ec78872a84213968c490675127b9aad2285980b747c68207801ae824b98c7948
          Linux_Alpine:
            unknown_versioning: *ghcup-64
        A_32:
          Linux_UnknownLinux:
            unknown_versioning: &ghcup-32
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.15.2/i386-linux-ghcup-0.1.15.2
-              dlHash: 3b1fe710cded0398e920ec9716089ba65226abf181741897f387e7c539a619c2
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/i386-linux-ghcup-0.1.16.2
+              dlHash: 01968ca6decac7b6e8ba6e2c817870d3fa47289a6507e0c1ab563f7b6eec0e38
          Linux_Alpine:
            unknown_versioning: *ghcup-32
        A_ARM64:
          Linux_UnknownLinux:
            unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.15.2/aarch64-linux-ghcup-0.1.15.2-r1
-              dlHash: d853372440f3d43babbb868fad399811241760f2233829c92403fcbea8c547ec
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/aarch64-linux-ghcup-0.1.16.2
+              dlHash: 0bdbfc724e0ddabb266156eea83c2c4e19c6ed79dd06db0c29b7d69df8d9fa8c
          Darwin:
            unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.15.2/aarch64-apple-darwin-ghcup-0.1.15.2
-              dlHash: 20625ba5e7488f2a6155331750ecead3815ea16b2695c20521633c1412f012cc
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/aarch64-apple-darwin-ghcup-0.1.16.2
+              dlHash: 8854e991a2ba1350abda59dab96ce50ae7729d1ce99399d67929ef31e90f1da5
        A_ARM:
          Linux_UnknownLinux:
            unknown_versioning:
-              dlUri: https://downloads.haskell.org/~ghcup/0.1.15.2/armv7-linux-ghcup-0.1.15.2-r1
-              dlHash: f8add9b39e1f7d0f03904dc69a8683259972a4472432c1ade27d918c39a4a874
+              dlUri: https://downloads.haskell.org/~ghcup/0.1.16.2/armv7-linux-ghcup-0.1.16.2
+              dlHash: 983ebb5b584bfa600704216a63f94b40d36a02573834e90ef1042c8472d9ad57
  HLS:
    1.1.0:
      viTags: []
      viChangeLog: https://github.com/haskell/haskell-language-server/blob/master/ChangeLog.md#110
-      viPostInstall: "This is just the server part of your LSP configuration. Consult the README on how to configure HLS, your project and your LSP client in your editor: https://github.com/haskell/haskell-language-server/blob/master/README.md"
+      viPostInstall: &hls-post-install |
+        This is just the server part of your LSP configuration. Consult the README on how to
+        configure HLS, your project and your LSP client in your editor:
+          https://github.com/haskell/haskell-language-server/blob/master/README.md
      viArch:
        A_64:
          Linux_UnknownLinux:
-            unknown_versioning: &hls-64
+            unknown_versioning: &hls-110-64
              dlUri: https://github.com/haskell/haskell-language-server/releases/download/1.1.0/haskell-language-server-Linux-1.1.0.tar.gz
              dlHash: 0f0dadb0e9a08273658f565fd71c636801959b954be2737f38f2a1aac522208f
          Darwin:
@@ -2091,17 +2095,15 @@ ghcupDownloads:
              dlUri: https://downloads.haskell.org/ghcup/unofficial-bindists/hls/1.1.0/haskell-language-server-Windows-1.1.0.tar.gz
              dlHash: a1d3f451e64a041aa527a25da29e4716a2de6ae347cef4ef9312fc7611e168cc
          Linux_Alpine:
-            unknown_versioning: *hls-64
+            unknown_versioning: *hls-110-64
    1.2.0:
-      viTags:
-        - Recommended
-        - Latest
+      viTags: []
      viChangeLog: https://github.com/haskell/haskell-language-server/blob/master/ChangeLog.md#120
-      viPostInstall: "This is just the server part of your LSP configuration. Consult the README on how to configure HLS, your project and your LSP client in your editor: https://github.com/haskell/haskell-language-server/blob/master/README.md"
+      viPostInstall: *hls-post-install
      viArch:
        A_64:
          Linux_UnknownLinux:
-            unknown_versioning: &hls-64
+            unknown_versioning: &hls-120-64
              dlUri: https://github.com/haskell/haskell-language-server/releases/download/1.2.0/haskell-language-server-Linux-1.2.0.tar.gz
              dlHash: d29ee22f7bd706da2e2a1bd7640e25bb9736adeafb34eef47d29ea143b0fa927
          Darwin:
@@ -2113,7 +2115,29 @@ ghcupDownloads:
              dlUri: https://github.com/haskell/haskell-language-server/releases/download/1.2.0/haskell-language-server-Windows-1.2.0.tar.gz
              dlHash: 961c6ff12c9a9c7a4609f239c5ac70d7d16753cdb8c10348a6a51feeaa0b6aea
          Linux_Alpine:
-            unknown_versioning: *hls-64
+            unknown_versioning: *hls-120-64
+    1.3.0:
+      viTags:
+        - Recommended
+        - Latest
+      viChangeLog: https://github.com/haskell/haskell-language-server/blob/master/ChangeLog.md#130
+      viPostInstall: *hls-post-install
+      viArch:
+        A_64:
+          Linux_UnknownLinux:
+            unknown_versioning: &hls-130-64
+              dlUri: https://github.com/haskell/haskell-language-server/releases/download/1.3.0/haskell-language-server-Linux-1.3.0.tar.gz
+              dlHash: d29ee22f7bd706da2e2a1bd7640e25bb9736adeafb34eef47d29ea143b0fa927
+          Darwin:
+            unknown_versioning:
+              dlUri: https://github.com/haskell/haskell-language-server/releases/download/1.3.0/haskell-language-server-macOS-1.3.0.tar.gz
+              dlHash: a310d8a3e9c5c4218210f750682c74a0f82ad0f59995adde0dbe775115b1e357
+          Windows:
+            unknown_versioning:
+              dlUri: https://github.com/haskell/haskell-language-server/releases/download/1.3.0/haskell-language-server-Windows-1.3.0.tar.gz
+              dlHash: 961c6ff12c9a9c7a4609f239c5ac70d7d16753cdb8c10348a6a51feeaa0b6aea
+          Linux_Alpine:
+            unknown_versioning: *hls-130-64
  Stack:
    2.5.1:
      viTags:
--- a/ghcup-0.0.6.yaml
+++ b/ghcup-0.0.6.yaml
--- a/ghcup.cabal
+++ b/ghcup.cabal
@@ -1,6 +1,6 @@
 cabal-version:   3.0
 name:            ghcup
-version:         0.1.15.2
+version:         0.1.16.2
 license:         LGPL-3.0-only
 license-file:    LICENSE
 copyright:       Julian Ospald 2020
@@ -20,6 +20,7 @@ extra-doc-files:
  config.yaml
  ghcup-0.0.4.yaml
  ghcup-0.0.5.yaml
+  ghcup-0.0.6.yaml
  HACKING.md
  README.md
  RELEASING.md
@@ -225,6 +226,7 @@ executable ghcup
    , uri-bytestring        ^>=0.3.2.2
    , utf8-string           ^>=1.0
    , versions              >=4.0.1    && <5.1
+    , yaml                  ^>=0.11.4.0

  if flag(internal-downloader)
    cpp-options: -DINTERNAL_DOWNLOADER
--- a/lib/GHCup.hs
+++ b/lib/GHCup.hs
@@ -186,6 +186,7 @@ installGHCBindist :: ( MonadFail m
                     )
                  => DownloadInfo    -- ^ where/how to download
                  -> Version         -- ^ the version to install
+                  -> Maybe FilePath  -- ^ isolated filepath if user passed any
                  -> Excepts
                       '[ AlreadyInstalled
                        , BuildFailed
@@ -195,16 +196,22 @@ installGHCBindist :: ( MonadFail m
                        , NotInstalled
                        , UnknownArchive
                        , TarDirDoesNotExist
+                        , DirNotEmpty
 #if !defined(TAR)
                        , ArchiveResult
 #endif
                        ]
                       m
                       ()
-installGHCBindist dlinfo ver = do
+installGHCBindist dlinfo ver isoFilepath = do
  let tver = mkTVer ver
+
  lift $ $(logDebug) [i|Requested to install GHC with #{ver}|]
-  whenM (lift $ ghcInstalled tver) (throwE $ AlreadyInstalled GHC ver)
+
+  case isoFilepath of
+    -- we only care for already installed errors in regular (non-isolated) installs
+    Nothing -> whenM (lift $ ghcInstalled tver) (throwE $ AlreadyInstalled GHC ver)
+    _ -> pure ()

  -- download (or use cached version)
  dl <- liftE $ downloadCached dlinfo Nothing
@@ -214,9 +221,15 @@ installGHCBindist dlinfo ver = do

  toolchainSanityChecks
  
-  liftE $ installPackedGHC dl (view dlSubdir dlinfo) ghcdir ver
+  case isoFilepath of
+    Just isoDir -> do                        -- isolated install
+      lift $ $(logInfo) [i|isolated installing GHC to #{isoDir}|]
+      liftE $ installPackedGHC dl (view dlSubdir dlinfo) isoDir ver
+    Nothing -> do                            -- regular install
+      liftE $ installPackedGHC dl (view dlSubdir dlinfo) ghcdir ver

-  liftE $ postGHCInstall tver
+      -- make symlinks & stuff when regular install,
+      liftE $ postGHCInstall tver

 where
  toolchainSanityChecks = do
@@ -250,6 +263,7 @@ installPackedGHC :: ( MonadMask m
                      '[ BuildFailed
                       , UnknownArchive
                       , TarDirDoesNotExist
+                       , DirNotEmpty
 #if !defined(TAR)
                       , ArchiveResult
 #endif
@@ -257,6 +271,8 @@ installPackedGHC :: ( MonadMask m
 installPackedGHC dl msubdir inst ver = do
  PlatformRequest {..} <- lift getPlatformReq

+  liftE $ installDestSanityCheck inst
+
  -- unpack
  tmpUnpack <- lift mkGhcupTmpDir
  liftE $ unpackToDir tmpUnpack dl
@@ -270,6 +286,22 @@ installPackedGHC dl msubdir inst ver = do
  liftE $ runBuildAction tmpUnpack
                         (Just inst)
                         (installUnpackedGHC workdir inst ver)
+ where
+  -- | Does basic checks for isolated installs
+  -- Isolated Directory:
+  --   1. if it doesn't exist -> proceed
+  --   2. if it exists and is empty -> proceed
+  --   3. if it exists and is non-empty -> panic and leave the house
+  installDestSanityCheck :: ( MonadIO m
+                            , MonadCatch m
+                            ) =>
+                            FilePath ->
+                            Excepts '[DirNotEmpty] m ()
+  installDestSanityCheck isoDir = do
+    hideErrorDef [doesNotExistErrorType] () $ do
+      contents <- liftIO $ getDirectoryContentsRecursive isoDir
+      unless (null contents) (throwE $ DirNotEmpty isoDir)
+


 -- | Install an unpacked GHC distribution. This only deals with the GHC
@@ -300,10 +332,6 @@ installUnpackedGHC path inst ver = do
    setModificationTime dest mtime
 #else
  PlatformRequest {..} <- lift getPlatformReq
-  liftIO $ copyDirectoryRecursive path inst $ \source dest -> do
-    mtime <- getModificationTime source
-    copyFile source dest
-    setModificationTime dest mtime

  let alpineArgs
       | ver >= [vver|8.2.2|], Linux Alpine <- _rPlatform
@@ -343,6 +371,7 @@ installGHCBin :: ( MonadFail m
                 , MonadUnliftIO m
                 )
              => Version         -- ^ the version to install
+              -> Maybe FilePath  -- ^ isolated install filepath, if user passed any
              -> Excepts
                   '[ AlreadyInstalled
                    , BuildFailed
@@ -352,15 +381,16 @@ installGHCBin :: ( MonadFail m
                    , NotInstalled
                    , UnknownArchive
                    , TarDirDoesNotExist
+                    , DirNotEmpty
 #if !defined(TAR)
                    , ArchiveResult
 #endif
                    ]
                   m
                   ()
-installGHCBin ver = do
+installGHCBin ver isoFilepath = do
  dlinfo <- liftE $ getDownloadInfo GHC ver
-  installGHCBindist dlinfo ver
+  installGHCBindist dlinfo ver isoFilepath


 -- | Like 'installCabalBin', except takes the 'DownloadInfo' as
@@ -379,6 +409,7 @@ installCabalBindist :: ( MonadMask m
                       )
                    => DownloadInfo
                    -> Version
+                    -> Maybe FilePath -- ^ isolated install filepath, if user provides any.
                    -> Excepts
                         '[ AlreadyInstalled
                          , CopyError
@@ -391,23 +422,28 @@ installCabalBindist :: ( MonadMask m
 #if !defined(TAR)
                          , ArchiveResult
 #endif
+                          , FileAlreadyExistsError
                          ]
                         m
                         ()
-installCabalBindist dlinfo ver = do
+installCabalBindist dlinfo ver isoFilepath = do
  lift $ $(logDebug) [i|Requested to install cabal version #{ver}|]

  PlatformRequest {..} <- lift getPlatformReq
  Dirs {..} <- lift getDirs

-  whenM
-      (lift (cabalInstalled ver) >>= \a -> liftIO $
-        handleIO (\_ -> pure False)
-          $ fmap (\x -> a && x)
-          -- ignore when the installation is a legacy cabal (binary, not symlink)
-          $ pathIsLink (binDir </> "cabal" <> exeExt)
-      )
-      (throwE $ AlreadyInstalled Cabal ver)
+  case isoFilepath of
+    Nothing -> -- for regular install check if any previous versions installed
+      whenM
+        (lift (cabalInstalled ver) >>= \a -> liftIO $
+          handleIO (\_ -> pure False)
+            $ fmap (\x -> a && x)
+            -- ignore when the installation is a legacy cabal (binary, not symlink)
+            $ pathIsLink (binDir </> "cabal" <> exeExt)
+        )
+        (throwE $ AlreadyInstalled Cabal ver)
+
+    _ -> pure () -- check isn't required in isolated installs

  -- download (or use cached version)
  dl <- liftE $ downloadCached dlinfo Nothing
@@ -420,30 +456,37 @@ installCabalBindist dlinfo ver = do
  -- the subdir of the archive where we do the work
  workdir <- maybe (pure tmpUnpack) (liftE . intoSubdir tmpUnpack) (view dlSubdir dlinfo)

-  liftE $ installCabal' workdir binDir
+  case isoFilepath of
+    Just isoDir -> do             -- isolated install
+      lift $ $(logInfo) [i|isolated installing Cabal to #{isoDir}|]
+      liftE $ installCabalUnpacked workdir isoDir Nothing

-  -- create symlink if this is the latest version
-  cVers <- lift $ fmap rights getInstalledCabals
-  let lInstCabal = headMay . reverse . sort $ cVers
-  when (maybe True (ver >=) lInstCabal) $ liftE $ setCabal ver
+    Nothing -> do                 -- regular install
+      liftE $ installCabalUnpacked workdir binDir (Just ver)

- where
-  -- | Install an unpacked cabal distribution.
-  installCabal' :: (MonadLogger m, MonadCatch m, MonadIO m)
-                => FilePath      -- ^ Path to the unpacked cabal bindist (where the executable resides)
-                -> FilePath      -- ^ Path to install to
-                -> Excepts '[CopyError] m ()
-  installCabal' path inst = do
-    lift $ $(logInfo) "Installing cabal"
-    let cabalFile = "cabal"
-    liftIO $ createDirRecursive' inst
-    let destFileName = cabalFile <> "-" <> T.unpack (prettyVer ver) <> exeExt
-    let destPath = inst </> destFileName
-    handleIO (throwE . CopyError . show) $ liftIO $ copyFile
-      (path </> cabalFile <> exeExt)
-      destPath
-    lift $ chmod_755 destPath
+      -- create symlink if this is the latest version for regular installs
+      cVers <- lift $ fmap rights getInstalledCabals
+      let lInstCabal = headMay . reverse . sort $ cVers
+      when (maybe True (ver >=) lInstCabal) $ liftE $ setCabal ver

+-- | Install an unpacked cabal distribution.
+installCabalUnpacked :: (MonadLogger m, MonadCatch m, MonadIO m)
+              => FilePath      -- ^ Path to the unpacked cabal bindist (where the executable resides)
+              -> FilePath      -- ^ Path to install to
+              -> Maybe Version -- ^ Nothing for isolated install
+              -> Excepts '[CopyError, FileAlreadyExistsError] m ()
+installCabalUnpacked path inst mver' = do
+  lift $ $(logInfo) "Installing cabal"
+  let cabalFile = "cabal"
+  liftIO $ createDirRecursive' inst
+  let destFileName = cabalFile
+        <> maybe "" (("-" <>) . T.unpack . prettyVer) mver'
+        <> exeExt
+  let destPath = inst </> destFileName
+  handleIO (throwE . CopyError . show) $ liftIO $ copyFile
+    (path </> cabalFile <> exeExt)
+    destPath
+  lift $ chmod_755 destPath

 -- | Installs cabal into @~\/.ghcup\/bin/cabal-\<ver\>@ and
 -- creates a default @cabal -> cabal-x.y.z.q@ symlink for
@@ -462,6 +505,7 @@ installCabalBin :: ( MonadMask m
                   , MonadFail m
                   )
                => Version
+                -> Maybe FilePath -- isolated install Path, if user provided any
                -> Excepts
                     '[ AlreadyInstalled
                      , CopyError
@@ -474,12 +518,13 @@ installCabalBin :: ( MonadMask m
 #if !defined(TAR)
                      , ArchiveResult
 #endif
+                      , FileAlreadyExistsError
                      ]
                     m
                     ()
-installCabalBin ver = do
+installCabalBin ver isoFilepath = do
  dlinfo <- liftE $ getDownloadInfo Cabal ver
-  installCabalBindist dlinfo ver
+  installCabalBindist dlinfo ver isoFilepath


 -- | Like 'installHLSBin, except takes the 'DownloadInfo' as
@@ -498,6 +543,7 @@ installHLSBindist :: ( MonadMask m
                     )
                  => DownloadInfo
                  -> Version
+                  -> Maybe FilePath -- ^ isolated install path, if user passed any
                  -> Excepts
                       '[ AlreadyInstalled
                        , CopyError
@@ -513,14 +559,19 @@ installHLSBindist :: ( MonadMask m
                        ]
                       m
                       ()
-installHLSBindist dlinfo ver = do
+installHLSBindist dlinfo ver isoFilepath = do
  lift $ $(logDebug) [i|Requested to install hls version #{ver}|]

  PlatformRequest {..} <- lift getPlatformReq
  Dirs {..} <- lift getDirs

-  whenM (lift (hlsInstalled ver))
-    (throwE $ AlreadyInstalled HLS ver)
+  case isoFilepath of
+    Nothing ->
+      -- we only check for already installed in regular (non-isolated) installs
+      whenM (lift (hlsInstalled ver))
+      (throwE $ AlreadyInstalled HLS ver)
+
+    _ -> pure ()

  -- download (or use cached version)
  dl <- liftE $ downloadCached dlinfo Nothing
@@ -533,46 +584,55 @@ installHLSBindist dlinfo ver = do
  -- the subdir of the archive where we do the work
  workdir <- maybe (pure tmpUnpack) (liftE . intoSubdir tmpUnpack) (view dlSubdir dlinfo)

-  liftE $ installHLS' workdir binDir
+  case isoFilepath of
+    Just isoDir -> do
+      lift $ $(logInfo) [i|isolated installing HLS to #{isoDir}|]
+      liftE $ installHLSUnpacked workdir isoDir Nothing

-  -- create symlink if this is the latest version
-  hlsVers <- lift $ fmap rights getInstalledHLSs
-  let lInstHLS = headMay . reverse . sort $ hlsVers
-  when (maybe True (ver >=) lInstHLS) $ liftE $ setHLS ver
+    Nothing -> do
+      liftE $ installHLSUnpacked workdir binDir (Just ver)

- where
-  -- | Install an unpacked hls distribution.
-  installHLS' :: (MonadFail m, MonadLogger m, MonadCatch m, MonadIO m)
-                => FilePath      -- ^ Path to the unpacked hls bindist (where the executable resides)
-                -> FilePath      -- ^ Path to install to
-                -> Excepts '[CopyError] m ()
-  installHLS' path inst = do
-    lift $ $(logInfo) "Installing HLS"
-    liftIO $ createDirRecursive' inst
+      -- create symlink if this is the latest version in a regular install
+      hlsVers <- lift $ fmap rights getInstalledHLSs
+      let lInstHLS = headMay . reverse . sort $ hlsVers
+      when (maybe True (ver >=) lInstHLS) $ liftE $ setHLS ver

-    -- install haskell-language-server-<ghcver>
-    bins@(_:_) <- liftIO $ findFiles
-      path
-      (makeRegexOpts compExtended
-                     execBlank
-                     ([s|^haskell-language-server-[0-9].*$|] :: ByteString)
-      )
-    forM_ bins $ \f -> do
-      let toF = dropSuffix exeExt f
-                <> "~" <> T.unpack (prettyVer ver) <> exeExt
-      handleIO (throwE . CopyError . show) $ liftIO $ copyFile
-        (path </> f)
-        (inst </> toF)
-      lift $ chmod_755 (inst </> toF)

-    -- install haskell-language-server-wrapper
-    let wrapper = "haskell-language-server-wrapper"
-        toF = wrapper <> "-" <> T.unpack (prettyVer ver) <> exeExt
+-- | Install an unpacked hls distribution.
+installHLSUnpacked :: (MonadFail m, MonadLogger m, MonadCatch m, MonadIO m)
+              => FilePath      -- ^ Path to the unpacked hls bindist (where the executable resides)
+              -> FilePath      -- ^ Path to install to
+              -> Maybe Version -- ^ Nothing for isolated install
+              -> Excepts '[CopyError] m ()
+installHLSUnpacked path inst mver' = do
+  lift $ $(logInfo) "Installing HLS"
+  liftIO $ createDirRecursive' inst
+
+  -- install haskell-language-server-<ghcver>
+  bins@(_:_) <- liftIO $ findFiles
+    path
+    (makeRegexOpts compExtended
+                   execBlank
+                   ([s|^haskell-language-server-[0-9].*$|] :: ByteString)
+    )
+  forM_ bins $ \f -> do
+    let toF = dropSuffix exeExt f
+              <> maybe "" (("~" <>) . T.unpack . prettyVer) mver'
+              <> exeExt
    handleIO (throwE . CopyError . show) $ liftIO $ copyFile
-      (path </> wrapper <> exeExt)
+      (path </> f)
      (inst </> toF)
    lift $ chmod_755 (inst </> toF)

+  -- install haskell-language-server-wrapper
+  let wrapper = "haskell-language-server-wrapper"
+      toF = wrapper
+            <> maybe "" (("-" <>) . T.unpack . prettyVer) mver'
+            <> exeExt
+  handleIO (throwE . CopyError . show) $ liftIO $ copyFile
+    (path </> wrapper <> exeExt)
+    (inst </> toF)
+  lift $ chmod_755 (inst </> toF)

 -- | Installs hls binaries @haskell-language-server-\<ghcver\>@
 -- into @~\/.ghcup\/bin/@, as well as @haskell-languager-server-wrapper@.
@@ -590,6 +650,7 @@ installHLSBin :: ( MonadMask m
                 , MonadFail m
                 )
              => Version
+              -> Maybe FilePath
              -> Excepts
                   '[ AlreadyInstalled
                    , CopyError
@@ -605,9 +666,9 @@ installHLSBin :: ( MonadMask m
                    ]
                   m
                   ()
-installHLSBin ver = do
+installHLSBin ver isoFilepath = do
  dlinfo <- liftE $ getDownloadInfo HLS ver
-  installHLSBindist dlinfo ver
+  installHLSBindist dlinfo ver isoFilepath


 -- | Installs stack into @~\/.ghcup\/bin/stack-\<ver\>@ and
@@ -627,6 +688,7 @@ installStackBin :: ( MonadMask m
                   , MonadFail m
                   )
                => Version
+                -> Maybe FilePath
                -> Excepts
                     '[ AlreadyInstalled
                      , CopyError
@@ -642,9 +704,9 @@ installStackBin :: ( MonadMask m
                      ]
                     m
                     ()
-installStackBin ver = do
+installStackBin ver isoFilepath = do
  dlinfo <- liftE $ getDownloadInfo Stack ver
-  installStackBindist dlinfo ver
+  installStackBindist dlinfo ver isoFilepath


 -- | Like 'installStackBin', except takes the 'DownloadInfo' as
@@ -663,6 +725,7 @@ installStackBindist :: ( MonadMask m
                       )
                    => DownloadInfo
                    -> Version
+                    -> Maybe FilePath
                    -> Excepts
                         '[ AlreadyInstalled
                          , CopyError
@@ -678,14 +741,18 @@ installStackBindist :: ( MonadMask m
                          ]
                         m
                         ()
-installStackBindist dlinfo ver = do
+installStackBindist dlinfo ver isoFilepath = do
  lift $ $(logDebug) [i|Requested to install stack version #{ver}|]

  PlatformRequest {..} <- lift getPlatformReq
  Dirs {..} <- lift getDirs

-  whenM (lift (stackInstalled ver))
-    (throwE $ AlreadyInstalled Stack ver)
+  case isoFilepath of
+    Nothing ->             -- check previous versions in case of regular installs
+      whenM (lift (stackInstalled ver))
+      (throwE $ AlreadyInstalled Stack ver)
+
+    _ -> pure ()           -- don't do shit for isolates

  -- download (or use cached version)
  dl <- liftE $ downloadCached dlinfo Nothing
@@ -698,31 +765,37 @@ installStackBindist dlinfo ver = do
  -- the subdir of the archive where we do the work
  workdir <- maybe (pure tmpUnpack) (liftE . intoSubdir tmpUnpack) (view dlSubdir dlinfo)

-  liftE $ installStack' workdir binDir
+  case isoFilepath of
+    Just isoDir -> do                 -- isolated install
+      lift $ $(logInfo) [i|isolated installing Stack to #{isoDir}|]
+      liftE $ installStackUnpacked workdir isoDir Nothing
+    Nothing -> do                     -- regular install
+      liftE $ installStackUnpacked workdir binDir (Just ver)

-  -- create symlink if this is the latest version
-  sVers <- lift $ fmap rights getInstalledStacks
-  let lInstStack = headMay . reverse . sort $ sVers
-  when (maybe True (ver >=) lInstStack) $ liftE $ setStack ver
-
- where
-  -- | Install an unpacked stack distribution.
-  installStack' :: (MonadLogger m, MonadCatch m, MonadIO m)
-                => FilePath      -- ^ Path to the unpacked stack bindist (where the executable resides)
-                -> FilePath      -- ^ Path to install to
-                -> Excepts '[CopyError] m ()
-  installStack' path inst = do
-    lift $ $(logInfo) "Installing stack"
-    let stackFile = "stack"
-    liftIO $ createDirRecursive' inst
-    let destFileName = stackFile <> "-" <> T.unpack (prettyVer ver) <> exeExt
-    let destPath = inst </> destFileName
-    handleIO (throwE . CopyError . show) $ liftIO $ copyFile
-      (path </> stackFile <> exeExt)
-      destPath
-    lift $ chmod_755 destPath
+      -- create symlink if this is the latest version and a regular install
+      sVers <- lift $ fmap rights getInstalledStacks
+      let lInstStack = headMay . reverse . sort $ sVers
+      when (maybe True (ver >=) lInstStack) $ liftE $ setStack ver


+-- | Install an unpacked stack distribution.
+installStackUnpacked :: (MonadLogger m, MonadCatch m, MonadIO m)
+              => FilePath      -- ^ Path to the unpacked stack bindist (where the executable resides)
+              -> FilePath      -- ^ Path to install to
+              -> Maybe Version -- ^ Nothing for isolated installs
+              -> Excepts '[CopyError] m ()
+installStackUnpacked path inst mver' = do
+  lift $ $(logInfo) "Installing stack"
+  let stackFile = "stack"
+  liftIO $ createDirRecursive' inst
+  let destFileName = stackFile
+                     <> maybe "" (("-" <>) .  T.unpack . prettyVer) mver'
+                     <> exeExt
+  let destPath = inst </> destFileName
+  handleIO (throwE . CopyError . show) $ liftIO $ copyFile
+    (path </> stackFile <> exeExt)
+    destPath
+  lift $ chmod_755 destPath


    ---------------------
@@ -965,9 +1038,9 @@ data ListResult = ListResult


 -- | Extract all available tool versions and their tags.
-availableToolVersions :: GHCupDownloads -> Tool -> Map.Map Version [Tag]
+availableToolVersions :: GHCupDownloads -> Tool -> Map.Map Version VersionInfo
 availableToolVersions av tool = view
-  (at tool % non Map.empty % to (fmap _viTags))
+  (at tool % non Map.empty)
  av


@@ -1018,7 +1091,9 @@ listVersions lt' criteria = do
          Stack -> do
            slr <- strayStacks avTools sSet stacks
            pure (sort (slr ++ lr))
-          GHCup -> pure lr
+          GHCup -> do
+            let cg = maybeToList $ currentGHCup avTools
+            pure (sort (cg ++ lr))
      Nothing -> do
        ghcvers   <- go (Just GHC) cSet cabals hlsSet' hlses sSet stacks
        cabalvers <- go (Just Cabal) cSet cabals hlsSet' hlses sSet stacks
@@ -1033,7 +1108,7 @@ listVersions lt' criteria = do
               , MonadLogger m
               , MonadIO m
               )
-            => Map.Map Version [Tag]
+            => Map.Map Version VersionInfo
            -> m [ListResult]
  strayGHCs avTools = do
    ghcs <- getInstalledGHCs
@@ -1081,7 +1156,7 @@ listVersions lt' criteria = do
                 , MonadLogger m
                 , MonadIO m
                 )
-            => Map.Map Version [Tag]
+            => Map.Map Version VersionInfo
            -> Maybe Version
            -> [Either FilePath Version]
            -> m [ListResult]
@@ -1115,7 +1190,7 @@ listVersions lt' criteria = do
              , MonadThrow m
              , MonadLogger m
              , MonadIO m)
-           => Map.Map Version [Tag]
+           => Map.Map Version VersionInfo
           -> Maybe Version
           -> [Either FilePath Version]
           -> m [ListResult]
@@ -1150,7 +1225,7 @@ listVersions lt' criteria = do
                 , MonadLogger m
                 , MonadIO m
                 )
-              => Map.Map Version [Tag]
+              => Map.Map Version VersionInfo
              -> Maybe Version
              -> [Either FilePath Version]
              -> m [ListResult]
@@ -1178,6 +1253,26 @@ listVersions lt' criteria = do
          [i|Could not parse version of stray directory #{e}|]
        pure Nothing

+  currentGHCup :: Map.Map Version VersionInfo -> Maybe ListResult
+  currentGHCup av =
+    let currentVer = pvpToVersion ghcUpVer
+        listVer    = Map.lookup currentVer av
+        latestVer  = fst <$> headOf (getTagged Latest) av
+        recommendedVer = fst <$> headOf (getTagged Latest) av
+        isOld  = maybe True (> currentVer) latestVer && maybe True (> currentVer) recommendedVer
+    in if | Map.member currentVer av -> Nothing
+          | otherwise -> Just $ ListResult { lVer    = currentVer
+                                           , lTag    = maybe (if isOld then [Old] else []) _viTags listVer
+                                           , lCross  = Nothing
+                                           , lTool   = GHCup
+                                           , fromSrc = False
+                                           , lStray  = isNothing listVer
+                                           , lSet    = True
+                                           , lInstalled = True
+                                           , lNoBindist = False
+                                           , hlsPowered = False
+                                           }
+
  -- NOTE: this are not cross ones, because no bindists
  toListResult :: ( MonadLogger m
                  , MonadReader env m
@@ -1194,9 +1289,9 @@ listVersions lt' criteria = do
               -> [Either FilePath Version]
               -> Maybe Version
               -> [Either FilePath Version]
-               -> (Version, [Tag])
+               -> (Version, VersionInfo)
               -> m ListResult
-  toListResult t cSet cabals hlsSet' hlses stackSet' stacks (v, tags) = do
+  toListResult t cSet cabals hlsSet' hlses stackSet' stacks (v, _viTags -> tags) = do
    case t of
      GHC -> do
        lNoBindist <- fmap (isLeft . veitherToEither) $ runE @'[NoDownload] $ getDownloadInfo GHC v
@@ -1520,8 +1615,11 @@ rmGhcupDirs = do

  handleRm $ rmEnvFile  envFilePath
  handleRm $ rmConfFile confFilePath
-  handleRm $ rmDir cacheDir
+  
+  -- for xdg dirs, the order matters here
  handleRm $ rmDir logsDir
+  handleRm $ rmDir cacheDir
+
  handleRm $ rmBinDir binDir
  handleRm $ rmDir recycleDir
 #if defined(IS_WINDOWS)
@@ -1537,18 +1635,18 @@ rmGhcupDirs = do

  where
    handleRm :: (MonadCatch m, MonadLogger m)  => m () -> m ()
-    handleRm = handleIO (\e -> $logWarn [i|Part of the cleanup action failed with error: #{displayException e}
+    handleRm = handleIO (\e -> $logDebug [i|Part of the cleanup action failed with error: #{displayException e}
 continuing regardless...|])

    rmEnvFile :: (MonadLogger m, MonadReader env m, HasDirs env, MonadMask m, MonadIO m, MonadCatch m) => FilePath -> m ()
    rmEnvFile enFilePath = do
      $logInfo "Removing Ghcup Environment File"
-      deleteFile enFilePath
+      hideErrorDef [permissionErrorType] () $ deleteFile enFilePath

    rmConfFile :: (MonadLogger m, MonadReader env m, HasDirs env, MonadMask m, MonadIO m, MonadCatch m) => FilePath -> m ()
    rmConfFile confFilePath = do
      $logInfo "removing Ghcup Config File"
-      deleteFile confFilePath
+      hideErrorDef [permissionErrorType] () $ deleteFile confFilePath

    rmDir :: (MonadLogger m, MonadReader env m, HasDirs env, MonadMask m, MonadIO m, MonadCatch m) => FilePath -> m ()
    rmDir dir =
@@ -1679,6 +1777,7 @@ compileGHC :: ( MonadMask m
           -> [Text]                   -- ^ additional args to ./configure
           -> Maybe String             -- ^ build flavour
           -> Bool
+           -> Maybe FilePath           -- ^ isolate dir
           -> Excepts
                '[ AlreadyInstalled
                 , BuildFailed
@@ -1691,13 +1790,14 @@ compileGHC :: ( MonadMask m
                 , UnknownArchive
                 , TarDirDoesNotExist
                 , NotInstalled
+                 , DirNotEmpty
 #if !defined(TAR)
                 , ArchiveResult
 #endif
                 ]
                m
                GHCTargetVersion
-compileGHC targetGhc ov bstrap jobs mbuildConfig patchdir aargs buildFlavour hadrian
+compileGHC targetGhc ov bstrap jobs mbuildConfig patchdir aargs buildFlavour hadrian isolateDir
  = do
    PlatformRequest { .. } <- lift getPlatformReq
    GHCupInfo { _ghcupDownloads = dls } <- lift getGHCupInfo
@@ -1767,12 +1867,18 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patchdir aargs buildFlavour had
    alreadyInstalled <- lift $ ghcInstalled installVer
    alreadySet <- fmap (== Just tver) $ lift $ ghcSet (_tvTarget tver)
    when alreadyInstalled $ do
-      lift $ $(logWarn) [i|GHC #{prettyShow tver} already installed. Will overwrite existing version.|]
+      case isolateDir of
+        Just isoDir ->
+          lift $ $(logWarn) [i|GHC #{prettyShow tver} already installed. Isolate installing to #{isoDir} |]
+        Nothing ->
+          lift $ $(logWarn) [i|GHC #{prettyShow tver} already installed. Will overwrite existing version.|]
      lift $ $(logWarn)
        "...waiting for 10 seconds before continuing, you can still abort..."
      liftIO $ threadDelay 10000000 -- give the user a sec to intervene

-    ghcdir         <- lift $ ghcupGHCDir installVer
+    ghcdir <- case isolateDir of
+      Just isoDir -> pure isoDir
+      Nothing -> lift $ ghcupGHCDir installVer

    bghc <- case bstrap of
      Right g    -> pure $ Right g
@@ -1789,9 +1895,14 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patchdir aargs buildFlavour had
        pure (b, bmk)
      )

-    when alreadyInstalled $ do
-      lift $ $(logInfo) [i|Deleting existing installation|]
-      liftE $ rmGHCVer tver
+    case isolateDir of
+      Nothing ->
+        -- only remove old ghc in regular installs
+        when alreadyInstalled $ do
+          lift $ $(logInfo) [i|Deleting existing installation|]
+          liftE $ rmGHCVer tver
+          
+      _ -> pure ()

    forM_ mBindist $ \bindist -> do
      liftE $ installPackedGHC bindist
@@ -1800,11 +1911,15 @@ compileGHC targetGhc ov bstrap jobs mbuildConfig patchdir aargs buildFlavour had
                               (tver ^. tvVersion)

    liftIO $ B.writeFile (ghcdir </> ghcUpSrcBuiltFile) bmk
-
-    reThrowAll GHCupSetError $ postGHCInstall tver
-
-    -- restore
-    when alreadySet $ liftE $ void $ setGHC tver SetGHCOnly
+    
+    case isolateDir of
+      -- set and make symlinks for regular (non-isolated) installs
+      Nothing -> do
+        reThrowAll GHCupSetError $ postGHCInstall tver
+        -- restore
+        when alreadySet $ liftE $ void $ setGHC tver SetGHCOnly
+        
+      _ -> pure ()

    pure tver

@@ -2012,7 +2127,7 @@ endif|]
        liftIO $ threadDelay 5000000

  addBuildFlavourToConf bc = case buildFlavour of
-    Just bf -> [i|BuildFlavour = #{bf}|] <> [s|
+    Just bf -> [i|BuildFlavour = #{bf}
 |] <> [i|#{bc}|]
    Nothing -> bc

@@ -2137,7 +2252,7 @@ upgradeGHCup mtarget force' = do
  dli   <- liftE $ getDownloadInfo GHCup latestVer
  tmp   <- lift withGHCupTmpDir
  let fn = "ghcup" <> exeExt
-  p <- liftE $ download dli tmp (Just fn)
+  p <- liftE $ download (_dlUri dli) (Just (_dlHash dli)) tmp (Just fn) False
  let destDir = takeDirectory destFile
      destFile = fromMaybe (binDir </> fn) mtarget
  lift $ $(logDebug) [i|mkdir -p #{destDir}|]
@@ -2164,6 +2279,7 @@ upgradeGHCup mtarget force' = do
    -------------


+
 -- | Creates @ghc-x.y.z@ and @ghc-x.y@ symlinks. This is used for
 -- both installing from source and bindist.
 postGHCInstall :: ( MonadReader env m
--- a/lib/GHCup/Download.hs
+++ b/lib/GHCup/Download.hs
@@ -55,20 +55,19 @@ import           Data.Aeson
 import           Data.Bifunctor
 import           Data.ByteString                ( ByteString )
 #if defined(INTERNAL_DOWNLOADER)
-import           Data.CaseInsensitive           ( CI )
+import           Data.CaseInsensitive           ( mk )
 #endif
 import           Data.List.Extra
 import           Data.Maybe
 import           Data.String.Interpolate
 import           Data.Time.Clock
 import           Data.Time.Clock.POSIX
-#if defined(INTERNAL_DOWNLOADER)
-import           Data.Time.Format
-#endif
 import           Data.Versions
-import           Data.Word8
-import           GHC.IO.Exception
+import           Data.Word8              hiding ( isSpace )
 import           Haskus.Utils.Variant.Excepts
+#if defined(INTERNAL_DOWNLOADER)
+import           Network.Http.Client     hiding ( URL )
+#endif
 import           Optics
 import           Prelude                 hiding ( abs
                                                , readFile
@@ -76,8 +75,11 @@ import           Prelude                 hiding ( abs
                                                )
 import           System.Directory
 import           System.Environment
+import           System.Exit
 import           System.FilePath
 import           System.IO.Error
+import           System.IO.Temp
+import           Text.PrettyPrint.HughesPJClass ( prettyShow )
 import           URI.ByteString

 import qualified Crypto.Hash.SHA256            as SHA256
@@ -85,10 +87,8 @@ import qualified Data.ByteString               as B
 import qualified Data.ByteString.Base16        as B16
 import qualified Data.ByteString.Lazy          as L
 import qualified Data.Map.Strict               as M
-#if defined(INTERNAL_DOWNLOADER)
-import qualified Data.CaseInsensitive          as CI
-#endif
 import qualified Data.Text                     as T
+import qualified Data.Text.IO                  as T
 import qualified Data.Text.Encoding            as E
 import qualified Data.Yaml                     as Y

@@ -149,19 +149,14 @@ getDownloadsF = do
    in GHCupInfo tr newDownloads newGlobalTools


-readFromCache :: ( MonadReader env m
-                 , HasDirs env
-                 , MonadIO m
-                 , MonadCatch m)
-              => URI
-              -> Excepts '[JSONError, FileDoesNotExistError] m L.ByteString
-readFromCache uri = do
-  Dirs{..} <- lift getDirs
-  let yaml_file = cacheDir </> (T.unpack . decUTF8Safe . urlBaseName . view pathL' $ uri)
-  handleIO' NoSuchThing (\_ -> throwE $ FileDoesNotExistError yaml_file)
-    . liftIO
-    . L.readFile
-    $ yaml_file
+yamlFromCache :: (MonadReader env m, HasDirs env) => URI -> m FilePath
+yamlFromCache uri = do
+  Dirs{..} <- getDirs
+  pure (cacheDir </> (T.unpack . decUTF8Safe . urlBaseName . view pathL' $ uri))
+
+
+etagsFile :: FilePath -> FilePath
+etagsFile = (<.> "etags")


 getBase :: ( MonadReader env m
@@ -174,33 +169,51 @@ getBase :: ( MonadReader env m
           , MonadMask m
           )
        => URI
-        -> Excepts '[JSONError , FileDoesNotExistError] m GHCupInfo
+        -> Excepts '[JSONError] m GHCupInfo
 getBase uri = do
  Settings { noNetwork } <- lift getSettings
-  bs <- if noNetwork
-        then readFromCache uri
-        else handleIO (\_ -> warnCache >> readFromCache uri)
-               . catchE @_ @'[JSONError, FileDoesNotExistError] (\(DownloadFailed _) -> warnCache >> readFromCache uri)
-               . reThrowAll @_ @_ @'[JSONError, DownloadFailed] DownloadFailed
-               $ smartDl uri
+
+  -- try to download yaml... usually this writes it into cache dir,
+  -- but in some cases not (e.g. when using file://), so we honour
+  -- the return filepath, if any
+  mYaml <- if noNetwork && view (uriSchemeL' % schemeBSL') uri /= "file" -- for file://, let it fall through
+           then pure Nothing
+           else handleIO (\e -> warnCache (displayException e) >> pure Nothing)
+               . catchE @_ @_ @'[] (\e@(DownloadFailed _) -> warnCache (prettyShow e) >> pure Nothing)
+               . reThrowAll @_ @_ @'[DownloadFailed] DownloadFailed
+               . fmap Just
+               . smartDl
+               $ uri
+
+  -- if we didn't get a filepath from the download, use the cached yaml
+  actualYaml <- maybe (lift $ yamlFromCache uri) pure mYaml
+  lift $ $(logDebug) [i|Decoding yaml at: #{actualYaml}|]
+
  liftE
-    . lE' @_ @_ @'[JSONError] JSONDecodeError
-    . first show
-    . Y.decodeEither'
-    . L.toStrict
-    $ bs
+    . onE_ (onError actualYaml)
+    . lEM' @_ @_ @'[JSONError] JSONDecodeError
+    . fmap (first (\e -> [i|#{displayException e}
+Consider removing "#{actualYaml}" manually.|]))
+    . liftIO
+    . Y.decodeFileEither
+    $ actualYaml
 where
-  warnCache = lift $ $(logWarn)
-      [i|Could not get download info, trying cached version (this may not be recent!)|]
+  -- On error, remove the etags file and set access time to 0. This should ensure the next invocation
+  -- may re-download and succeed.
+  onError :: (MonadLogger m, MonadMask m, MonadCatch m, MonadIO m) => FilePath -> m ()
+  onError fp = do
+    let efp = etagsFile fp
+    handleIO (\e -> $(logWarn) [i|Couldn't remove file #{efp}, error was: #{displayException e}|])
+      (hideError doesNotExistErrorType $ rmFile efp)
+    liftIO $ hideError doesNotExistErrorType $ setAccessTime fp (posixSecondsToUTCTime (fromIntegral @Int 0))
+  warnCache s = do
+    lift $ $(logWarn) [i|Could not get download info, trying cached version (this may not be recent!)|]
+    lift $ $(logDebug) [i|Error was: #{s}|]

  -- First check if the json file is in the ~/.ghcup/cache dir
  -- and check it's access time. If it has been accessed within the
  -- last 5 minutes, just reuse it.
  --
-  -- If not, then send a HEAD request and check for modification time.
-  -- Only download the file if the modification time is newer
-  -- than the local file.
-  --
  -- Always save the local file with the mod time of the remote file.
  smartDl :: forall m1 env1
           . ( MonadReader env1 m1
@@ -214,92 +227,36 @@ getBase uri = do
             )
          => URI
          -> Excepts
-               '[ FileDoesNotExistError
-                , HTTPStatusError
-                , URIParseError
-                , UnsupportedScheme
-                , NoLocationHeader
-                , TooManyRedirs
-                , ProcessError
-                , NoNetwork
+               '[ DownloadFailed
+                , DigestError
                ]
               m1
-               L.ByteString
+               FilePath
  smartDl uri' = do
-    Dirs{..} <- lift getDirs
-    let path = view pathL' uri'
-    let json_file = cacheDir </> (T.unpack . decUTF8Safe . urlBaseName $ path)
+    json_file <- lift $ yamlFromCache uri'
+    let scheme = view (uriSchemeL' % schemeBSL') uri'
    e <- liftIO $ doesFileExist json_file
-    if e
-      then do
-        accessTime <- liftIO $ getAccessTime json_file
-        currentTime <- liftIO getCurrentTime
+    currentTime <- liftIO getCurrentTime
+    Dirs { cacheDir } <- lift getDirs

-        -- access time won't work on most linuxes, but we can try regardless
-        if (utcTimeToPOSIXSeconds currentTime - utcTimeToPOSIXSeconds accessTime) > 300
-          then do -- no access in last 5 minutes, re-check upstream mod time
-            getModTime >>= \case
-              Just modTime -> do
-                fileMod <- liftIO $ getModificationTime json_file
-                if modTime > fileMod
-                  then dlWithMod modTime json_file
-                  else liftIO $ L.readFile json_file
-              Nothing -> do
-                lift $ $(logDebug) [i|Unable to get/parse Last-Modified header|]
-                dlWithoutMod json_file
-          else -- access in less than 5 minutes, re-use file
-               liftIO $ L.readFile json_file
-      else do
-        getModTime >>= \case
-          Just modTime -> dlWithMod modTime json_file
-          Nothing -> do
-            -- although we don't know last-modified, we still save
-            -- it to a file, so we might use it in offline mode
-            lift $ $(logDebug) [i|Unable to get/parse Last-Modified header|]
-            dlWithoutMod json_file
+       -- for local files, let's short-circuit and ignore access time
+    if | scheme == "file" -> liftE $ download uri' Nothing cacheDir Nothing True
+       | e -> do
+          accessTime <- liftIO $ getAccessTime json_file

+          -- access time won't work on most linuxes, but we can try regardless
+          if | ((utcTimeToPOSIXSeconds currentTime - utcTimeToPOSIXSeconds accessTime) > 300) ->
+                -- no access in last 5 minutes, re-check upstream mod time
+                dlWithMod currentTime json_file
+             | otherwise -> pure json_file
+       | otherwise -> dlWithMod currentTime json_file
   where
    dlWithMod modTime json_file = do
-      bs <- liftE $ downloadBS uri'
-      liftIO $ writeFileWithModTime modTime json_file bs
-      pure bs
-    dlWithoutMod json_file = do
-      bs <- liftE $ downloadBS uri'
-      lift $ hideError doesNotExistErrorType $ recycleFile json_file
-      liftIO $ L.writeFile json_file bs
-      liftIO $ setModificationTime json_file (posixSecondsToUTCTime (fromIntegral @Int 0))
-      pure bs
-
-
-    getModTime = do
-#if !defined(INTERNAL_DOWNLOADER)
-      pure Nothing
-#else
-      headers <-
-        handleIO (\_ -> pure mempty)
-        $ liftE
-        $ ( catchAllE
-              (\_ ->
-                pure mempty :: Excepts '[] m1 (M.Map (CI ByteString) ByteString)
-              )
-          $ getHead uri'
-          )
-      pure $ parseModifiedHeader headers
-
-  parseModifiedHeader :: (M.Map (CI ByteString) ByteString) -> Maybe UTCTime
-  parseModifiedHeader headers =
-    (M.lookup (CI.mk "Last-Modified") headers) >>= \h -> parseTimeM
-      True
-      defaultTimeLocale
-      "%a, %d %b %Y %H:%M:%S %Z"
-      (T.unpack . decUTF8Safe $ h)
-
-#endif
-
-  writeFileWithModTime :: UTCTime -> FilePath -> L.ByteString -> IO ()
-  writeFileWithModTime utctime path content = do
-    L.writeFile path content
-    setModificationTime path utctime
+      let (dir, fn) = splitFileName json_file
+      f <- liftE $ download uri' Nothing dir (Just fn) True
+      liftIO $ setModificationTime f modTime
+      liftIO $ setAccessTime f modTime
+      pure f


 getDownloadInfo :: ( MonadReader env m
@@ -359,32 +316,30 @@ download :: ( MonadReader env m
            , MonadLogger m
            , MonadIO m
            )
-         => DownloadInfo
-         -> FilePath          -- ^ destination dir
+         => URI
+         -> Maybe T.Text      -- ^ expected hash
+         -> FilePath          -- ^ destination dir (ignored for file:// scheme)
         -> Maybe FilePath    -- ^ optional filename
+         -> Bool              -- ^ whether to read an write etags
         -> Excepts '[DigestError , DownloadFailed] m FilePath
-download dli dest mfn
+download uri eDigest dest mfn etags
  | scheme == "https" = dl
  | scheme == "http"  = dl
-  | scheme == "file"  = cp
+  | scheme == "file"  = do
+      let destFile' = T.unpack . decUTF8Safe $ path
+      lift $ $(logDebug) [i|using local file: #{destFile'}|]
+      forM_ eDigest (liftE . flip checkDigest destFile')
+      pure destFile'
  | otherwise = throwE $ DownloadFailed (variantFromValue UnsupportedScheme)

 where
-  scheme = view (dlUri % uriSchemeL' % schemeBSL') dli
-  cp     = do
-    -- destination dir must exist
-    liftIO $ createDirRecursive' dest
-    let destFile = getDestFile
-    let fromFile = T.unpack . decUTF8Safe $ path
-    liftIO $ copyFile fromFile destFile
-    pure destFile
+  scheme = view (uriSchemeL' % schemeBSL') uri
  dl = do
-    let uri' = decUTF8Safe (serializeURIRef' (view dlUri dli))
-    lift $ $(logInfo) [i|downloading: #{uri'}|]
+    destFile <- liftE . reThrowAll @_ @_ @'[DownloadFailed] DownloadFailed $ getDestFile
+    lift $ $(logInfo) [i|downloading: #{uri'} as file #{destFile}|]

    -- destination dir must exist
    liftIO $ createDirRecursive' dest
-    let destFile = getDestFile

    -- download
    flip onException
@@ -399,28 +354,140 @@ download dli dest mfn
              case downloader of
                Curl -> do
                  o' <- liftIO getCurlOpts
-                  liftE $ lEM @_ @'[ProcessError] $ exec "curl" 
-                    (o' ++ ["-fL", "-o", destFile, (T.unpack . decUTF8Safe) $ serializeURIRef' $ view dlUri dli]) Nothing Nothing
+                  if etags
+                    then do
+                      dh <- liftIO $ emptySystemTempFile "curl-header"
+                      flip finally (try @_ @SomeException $ rmFile dh) $
+                        flip finally (try @_ @SomeException $ rmFile (destFile <.> "tmp")) $ do
+                          metag <- readETag destFile
+                          liftE $ lEM @_ @'[ProcessError] $ exec "curl"
+                              (o' ++ (if etags then ["--dump-header", dh] else [])
+                                  ++ maybe [] (\t -> ["-H", [i|If-None-Match: #{t}|]]) metag
+                                  ++ ["-fL", "-o", destFile <.> "tmp", T.unpack uri']) Nothing Nothing
+                          headers <- liftIO $ T.readFile dh
+
+                          -- this nonsense is necessary, because some older versions of curl would overwrite
+                          -- the destination file when 304 is returned
+                          case fmap T.words . listToMaybe . fmap T.strip . T.lines $ headers of
+                            Just (http':sc:_)
+                              | sc == "304"
+                              , T.pack "HTTP" `T.isPrefixOf` http' -> $logDebug [i|Status code was 304, not overwriting|]
+                              | T.pack "HTTP" `T.isPrefixOf` http' -> do
+                                  $logDebug [i|Status code was #{sc}, overwriting|]
+                                  liftIO $ copyFile (destFile <.> "tmp") destFile
+                            _ -> liftE $ throwE @_ @'[DownloadFailed] (DownloadFailed (toVariantAt @0 (MalformedHeaders headers)
+                              :: V '[MalformedHeaders]))
+
+                          writeEtags destFile (parseEtags headers)
+                    else
+                      liftE $ lEM @_ @'[ProcessError] $ exec "curl" 
+                        (o' ++ ["-fL", "-o", destFile, T.unpack uri']) Nothing Nothing
                Wget -> do
-                  o' <- liftIO getWgetOpts
-                  liftE $ lEM @_ @'[ProcessError] $ exec "wget" 
-                    (o' ++ ["-O", destFile , (T.unpack . decUTF8Safe) $ serializeURIRef' $ view dlUri dli]) Nothing Nothing
+                  destFileTemp <- liftIO $ emptySystemTempFile "wget-tmp"
+                  flip finally (try @_ @SomeException $ rmFile destFileTemp) $ do
+                    o' <- liftIO getWgetOpts
+                    if etags
+                      then do
+                        metag <- readETag destFile
+                        let opts = o' ++ maybe [] (\t -> ["--header", [i|If-None-Match: #{t}|]]) metag
+                                      ++ ["-q", "-S", "-O", destFileTemp , T.unpack uri']
+                        CapturedProcess {_exitCode, _stdErr} <- lift $ executeOut "wget" opts Nothing
+                        case _exitCode of
+                          ExitSuccess -> do
+                            liftIO $ copyFile destFileTemp destFile
+                            writeEtags destFile (parseEtags (decUTF8Safe' _stdErr))
+                          ExitFailure i'
+                            | i' == 8
+                            , Just _ <- find (T.pack "304 Not Modified" `T.isInfixOf`) . T.lines . decUTF8Safe' $ _stdErr
+                                     -> do
+                                          $logDebug "Not modified, skipping download"
+                                          writeEtags destFile (parseEtags (decUTF8Safe' _stdErr))
+                            | otherwise -> throwE (NonZeroExit i' "wget" opts)
+                      else do
+                        let opts = o' ++ ["-O", destFileTemp , T.unpack uri']
+                        liftE $ lEM @_ @'[ProcessError] $ exec "wget" opts Nothing Nothing
+                        liftIO $ copyFile destFileTemp destFile
 #if defined(INTERNAL_DOWNLOADER)
                Internal -> do
-                  (https, host, fullPath, port) <- liftE $ uriToQuadruple (view dlUri dli)
-                  liftE $ downloadToFile https host fullPath port destFile
+                  (https, host, fullPath, port) <- liftE $ uriToQuadruple uri
+                  if etags
+                    then do
+                      metag <- readETag destFile
+                      let addHeaders = maybe mempty (\etag -> M.fromList [ (mk . E.encodeUtf8 . T.pack $ "If-None-Match"
+                                                                         , E.encodeUtf8 etag)]) metag
+                      liftE
+                        $ catchE @HTTPNotModified @'[DownloadFailed] @'[] (\(HTTPNotModified etag) -> lift $ writeEtags destFile (pure $ Just etag))
+                        $ do
+                          r <- downloadToFile https host fullPath port destFile addHeaders
+                          writeEtags destFile (pure $ decUTF8Safe <$> getHeader r "etag")
+                    else void $ liftE $ catchE @HTTPNotModified
+                                        @'[DownloadFailed]
+                                   (\e@(HTTPNotModified _) ->
+                                     throwE @_ @'[DownloadFailed] (DownloadFailed (toVariantAt @0 e :: V '[HTTPNotModified])))
+                               $ downloadToFile https host fullPath port destFile mempty
 #endif

-    liftE $ checkDigest dli destFile
+    forM_ eDigest (liftE . flip checkDigest destFile)
    pure destFile

-  -- Manage to find a file we can write the body into.
-  getDestFile :: FilePath
-  getDestFile = maybe (dest </> T.unpack (decUTF8Safe (urlBaseName path)))
-                  (dest </>)
-                  mfn

-  path = view (dlUri % pathL') dli
+  -- Manage to find a file we can write the body into.
+  getDestFile :: Monad m => Excepts '[NoUrlBase] m FilePath
+  getDestFile = 
+    case mfn of
+        Just fn -> pure (dest </> fn)
+        Nothing
+          | let urlBase = T.unpack (decUTF8Safe (urlBaseName path))
+          , not (null urlBase) -> pure (dest </> urlBase)
+          -- TODO: remove this once we use hpath again
+          | otherwise -> throwE $ NoUrlBase uri'
+
+  path = view pathL' uri
+  uri' = decUTF8Safe (serializeURIRef' uri)
+
+  parseEtags :: (MonadLogger m, MonadIO m, MonadThrow m) => T.Text -> m (Maybe T.Text)
+  parseEtags stderr = do
+    let mEtag = find (\line -> T.pack "etag:" `T.isPrefixOf` T.toLower line) . fmap T.strip . T.lines $ stderr
+    case T.words <$> mEtag of
+      (Just []) -> do
+        $logDebug "Couldn't parse etags, no input: "
+        pure Nothing
+      (Just [_, etag']) -> do
+        $logDebug [i|Parsed etag: #{etag'}|]
+        pure (Just etag')
+      (Just xs) -> do
+        $logDebug ("Couldn't parse etags, unexpected input: " <> T.unwords xs)
+        pure Nothing
+      Nothing -> do
+        $logDebug "No etags header found"
+        pure Nothing
+
+  writeEtags :: (MonadLogger m, MonadIO m, MonadThrow m) => FilePath -> m (Maybe T.Text) -> m ()
+  writeEtags destFile getTags = do
+    getTags >>= \case
+      Just t -> do
+        $logDebug [i|Writing etagsFile #{(etagsFile destFile)}|]
+        liftIO $ T.writeFile (etagsFile destFile) t
+      Nothing ->
+        $logDebug [i|No etags files written|]
+
+  readETag :: (MonadLogger m, MonadCatch m, MonadIO m) => FilePath -> m (Maybe T.Text)
+  readETag fp = do
+    e <- liftIO $ doesFileExist fp
+    if e
+    then do
+      rE <- try @_ @SomeException $ liftIO $ fmap stripNewline' $ T.readFile (etagsFile fp)
+      case rE of
+        (Right et) -> do
+          $logDebug [i|Read etag: #{et}|]
+          pure (Just et)
+        (Left _) -> do
+          $logDebug [i|Etag file doesn't exist (yet)|]
+          pure Nothing
+    else do
+      $logDebug [i|Skipping and deleting etags file because destination file #{fp} doesn't exist|]
+      liftIO $ hideError doesNotExistErrorType $ rmFile (etagsFile fp)
+      pure Nothing


 -- | Download into tmpdir or use cached version, if it exists. If filename
@@ -444,7 +511,7 @@ downloadCached dli mfn = do
    True -> downloadCached' dli mfn Nothing
    False -> do
      tmp <- lift withGHCupTmpDir
-      liftE $ download dli tmp mfn
+      liftE $ download (_dlUri dli) (Just (_dlHash dli)) tmp mfn False


 downloadCached' :: ( MonadReader env m
@@ -468,9 +535,9 @@ downloadCached' dli mfn mDestDir = do
  fileExists <- liftIO $ doesFileExist cachfile
  if
    | fileExists -> do
-      liftE $ checkDigest dli cachfile
+      liftE $ checkDigest (view dlHash dli) cachfile
      pure cachfile
-    | otherwise -> liftE $ download dli destDir mfn
+    | otherwise -> liftE $ download (_dlUri dli) (Just (_dlHash dli)) destDir mfn False



@@ -481,73 +548,6 @@ downloadCached' dli mfn mDestDir = do



-
-- | This is used for downloading the JSON.
-downloadBS :: ( MonadReader env m
-              , HasSettings env
-              , MonadCatch m
-              , MonadIO m
-              , MonadLogger m
-              )
-           => URI
-           -> Excepts
-                '[ FileDoesNotExistError
-                 , HTTPStatusError
-                 , URIParseError
-                 , UnsupportedScheme
-                 , NoLocationHeader
-                 , TooManyRedirs
-                 , ProcessError
-                 , NoNetwork
-                 ]
-                m
-                L.ByteString
-downloadBS uri'
-  | scheme == "https"
-  = dl True
-  | scheme == "http"
-  = dl False
-  | scheme == "file"
-  = liftIOException doesNotExistErrorType (FileDoesNotExistError $ T.unpack $ decUTF8Safe path)
-    (liftIO $ L.readFile (T.unpack $ decUTF8Safe path))
-  | otherwise
-  = throwE UnsupportedScheme
-
- where
-  scheme = view (uriSchemeL' % schemeBSL') uri'
-  path   = view pathL' uri'
-#if defined(INTERNAL_DOWNLOADER)
-  dl https = do
-#else
-  dl _ = do
-#endif
-    lift $ $(logDebug) [i|downloading: #{serializeURIRef' uri'}|]
-    Settings{ downloader, noNetwork } <- lift getSettings
-    when noNetwork $ throwE NoNetwork
-    case downloader of
-      Curl -> do
-        o' <- liftIO getCurlOpts
-        let exe = "curl"
-            args = o' ++ ["-sSfL", T.unpack $ decUTF8Safe $ serializeURIRef' uri']
-        lift (executeOut exe args Nothing) >>= \case
-          CapturedProcess ExitSuccess stdout _ -> do
-            pure stdout
-          CapturedProcess (ExitFailure i') _ _ -> throwE $ NonZeroExit i' exe args
-      Wget -> do
-        o' <- liftIO getWgetOpts
-        let exe = "wget"
-            args = o' ++ ["-qO-", T.unpack $ decUTF8Safe $ serializeURIRef' uri']
-        lift (executeOut exe args Nothing) >>= \case
-          CapturedProcess ExitSuccess stdout _ -> do
-            pure stdout
-          CapturedProcess (ExitFailure i') _ _ -> throwE $ NonZeroExit i' exe args
-#if defined(INTERNAL_DOWNLOADER)
-      Internal -> do
-        (_, host', fullPath', port') <- liftE $ uriToQuadruple uri'
-        liftE $ downloadBS' https host' fullPath' port'
-#endif
-
-
 checkDigest :: ( MonadReader env m
               , HasDirs env
               , HasSettings env
@@ -555,10 +555,10 @@ checkDigest :: ( MonadReader env m
               , MonadThrow m
               , MonadLogger m
               )
-            => DownloadInfo
+            => T.Text     -- ^ the hash
            -> FilePath
            -> Excepts '[DigestError] m ()
-checkDigest dli file = do
+checkDigest eDigest file = do
  Settings{ noVerify } <- lift getSettings
  let verify = not noVerify
  when verify $ do
@@ -566,7 +566,6 @@ checkDigest dli file = do
    lift $ $(logInfo) [i|verifying digest of: #{p'}|]
    c <- liftIO $ L.readFile file
    cDigest <- throwEither . E.decodeUtf8' . B16.encode . SHA256.hashlazy $ c
-    let eDigest = view dlHash dli
    when ((cDigest /= eDigest) && verify) $ throwE (DigestError cDigest eDigest)


--- a/lib/GHCup/Download/IOStreams.hs
+++ b/lib/GHCup/Download/IOStreams.hs
@@ -9,9 +9,7 @@ module GHCup.Download.IOStreams where

 import           GHCup.Download.Utils
 import           GHCup.Errors
-import           GHCup.Types.Optics
 import           GHCup.Types.JSON               ( )
-import           GHCup.Utils.File
 import           GHCup.Utils.Prelude

 import           Control.Applicative
@@ -20,7 +18,7 @@ import           Control.Monad
 import           Control.Monad.Reader
 import           Data.ByteString                ( ByteString )
 import           Data.ByteString.Builder
-import           Data.CaseInsensitive           ( CI )
+import           Data.CaseInsensitive           ( CI, original, mk )
 import           Data.IORef
 import           Data.Maybe
 import           Data.Text.Read
@@ -32,7 +30,6 @@ import           Prelude                 hiding ( abs
                                                , writeFile
                                                )
 import           System.ProgressBar
-import           System.IO
 import           URI.ByteString

 import qualified Data.ByteString               as BS
@@ -67,7 +64,7 @@ downloadBS' :: MonadIO m
 downloadBS' https host path port = do
  bref <- liftIO $ newIORef (mempty :: Builder)
  let stepper bs = modifyIORef bref (<> byteString bs)
-  downloadInternal False https host path port stepper
+  void $ downloadInternal False https host path port stepper (pure ()) mempty
  liftIO (readIORef bref <&> toLazyByteString)


@@ -77,12 +74,17 @@ downloadToFile :: (MonadMask m, MonadIO m)
               -> ByteString       -- ^ path (e.g. "/my/file") including query
               -> Maybe Int        -- ^ optional port (e.g. 3000)
               -> FilePath         -- ^ destination file to create and write to
-               -> Excepts '[DownloadFailed] m ()
-downloadToFile https host fullPath port destFile = do
-  fd <- liftIO $ openFile destFile WriteMode
-  let stepper = BS.hPut fd
-  flip finally (liftIO $ hClose fd)
-    $ reThrowAll DownloadFailed $ downloadInternal True https host fullPath port stepper
+               -> M.Map (CI ByteString) ByteString -- ^ additional headers
+               -> Excepts '[DownloadFailed, HTTPNotModified] m Response
+downloadToFile https host fullPath port destFile addHeaders = do
+  let stepper = BS.appendFile destFile
+      setup = BS.writeFile destFile mempty
+  catchAllE (\case
+              (V (HTTPStatusError i headers))
+                | i == 304
+                , Just e <- M.lookup (mk "etag") headers -> throwE $ HTTPNotModified (decUTF8Safe e)
+              v -> throwE $ DownloadFailed v
+            ) $ downloadInternal True https host fullPath port stepper setup addHeaders


 downloadInternal :: MonadIO m
@@ -92,6 +94,8 @@ downloadInternal :: MonadIO m
                 -> ByteString  -- ^ path with query
                 -> Maybe Int   -- ^ optional port
                 -> (ByteString -> IO a)   -- ^ the consuming step function
+                 -> IO a                   -- ^ setup action
+                 -> M.Map (CI ByteString) ByteString -- ^ additional headers
                 -> Excepts
                      '[ HTTPStatusError
                       , URIParseError
@@ -100,19 +104,21 @@ downloadInternal :: MonadIO m
                       , TooManyRedirs
                       ]
                      m
-                      ()
+                      Response
 downloadInternal = go (5 :: Int)

 where
-  go redirs progressBar https host path port consumer = do
+  go redirs progressBar https host path port consumer setup addHeaders = do
    r <- liftIO $ withConnection' https host port action
    veitherToExcepts r >>= \case
-      Just r' ->
+      Right r' ->
        if redirs > 0 then followRedirectURL r' else throwE TooManyRedirs
-      Nothing -> pure ()
+      Left res -> pure res
   where
    action c = do
-      let q = buildRequest1 $ http GET path
+      let q = buildRequest1 $ do
+                http GET path
+                flip M.traverseWithKey addHeaders $ \key val -> setHeader (original key) val

      sendRequest c q emptyBody

@@ -121,28 +127,30 @@ downloadInternal = go (5 :: Int)
        (\r i' -> runE $ do
          let scode = getStatusCode r
          if
-            | scode >= 200 && scode < 300 -> downloadStream r i' >> pure Nothing
+            | scode >= 200 && scode < 300 -> liftIO $ downloadStream r i' >> pure (Left r)
+            | scode == 304 -> throwE $ HTTPStatusError scode (getHeaderMap r)
            | scode >= 300 && scode < 400 -> case getHeader r "Location" of
-              Just r' -> pure $ Just r'
+              Just r' -> pure $ Right r'
              Nothing -> throwE NoLocationHeader
-            | otherwise -> throwE $ HTTPStatusError scode
+            | otherwise -> throwE $ HTTPStatusError scode (getHeaderMap r)
        )

    followRedirectURL bs = case parseURI strictURIParserOptions bs of
      Right uri' -> do
        (https', host', fullPath', port') <- liftE $ uriToQuadruple uri'
-        go (redirs - 1) progressBar https' host' fullPath' port' consumer
+        go (redirs - 1) progressBar https' host' fullPath' port' consumer setup addHeaders
      Left e -> throwE e

    downloadStream r i' = do
+      void setup
      let size = case getHeader r "Content-Length" of
            Just x' -> case decimal $ decUTF8Safe x' of
              Left  _       -> 0
              Right (r', _) -> r'
            Nothing -> 0

-      mpb <- if progressBar
-        then Just <$> liftIO (newProgressBar defStyle 10 (Progress 0 size ()))
+      (mpb :: Maybe (ProgressBar ())) <- if progressBar
+        then Just <$> newProgressBar defStyle 10 (Progress 0 size ())
        else pure Nothing

      outStream <- liftIO $ Streams.makeOutputStream
@@ -155,79 +163,6 @@ downloadInternal = go (5 :: Int)
      liftIO $ Streams.connect i' outStream


-getHead :: (MonadCatch m, MonadIO m)
-        => URI
-        -> Excepts
-             '[ HTTPStatusError
-              , URIParseError
-              , UnsupportedScheme
-              , NoLocationHeader
-              , TooManyRedirs
-              , ProcessError
-              ]
-             m
-             (M.Map (CI ByteString) ByteString)
-getHead uri' | scheme == "https" = head' True
-             | scheme == "http"  = head' False
-             | otherwise         = throwE UnsupportedScheme
-
- where
-  scheme = view (uriSchemeL' % schemeBSL') uri'
-  head' https = do
-    (_, host', fullPath', port') <- liftE $ uriToQuadruple uri'
-    liftE $ headInternal https host' fullPath' port'
-
-
-headInternal :: MonadIO m
-             => Bool        -- ^ https?
-             -> ByteString  -- ^ host
-             -> ByteString  -- ^ path with query
-             -> Maybe Int   -- ^ optional port
-             -> Excepts
-                  '[ HTTPStatusError
-                   , URIParseError
-                   , UnsupportedScheme
-                   , TooManyRedirs
-                   , NoLocationHeader
-                   ]
-                  m
-                  (M.Map (CI ByteString) ByteString)
-headInternal = go (5 :: Int)
-
- where
-  go redirs https host path port = do
-    r <- liftIO $ withConnection' https host port action
-    veitherToExcepts r >>= \case
-      Left r' ->
-        if redirs > 0 then followRedirectURL r' else throwE TooManyRedirs
-      Right hs -> pure hs
-   where
-
-    action c = do
-      let q = buildRequest1 $ http HEAD path
-
-      sendRequest c q emptyBody
-
-      unsafeReceiveResponse
-        c
-        (\r _ -> runE $ do
-          let scode = getStatusCode r
-          if
-            | scode >= 200 && scode < 300 -> do
-              let headers = getHeaderMap r
-              pure $ Right headers
-            | scode >= 300 && scode < 400 -> case getHeader r "Location" of
-              Just r' -> pure $ Left r'
-              Nothing -> throwE NoLocationHeader
-            | otherwise -> throwE $ HTTPStatusError scode
-        )
-
-    followRedirectURL bs = case parseURI strictURIParserOptions bs of
-      Right uri' -> do
-        (https', host', fullPath', port') <- liftE $ uriToQuadruple uri'
-        go (redirs - 1) https' host' fullPath' port'
-      Left e -> throwE e
-

 withConnection' :: Bool
                -> ByteString
--- a/lib/GHCup/Errors.hs
+++ b/lib/GHCup/Errors.hs
@@ -27,6 +27,8 @@ import           Codec.Archive
 import qualified Codec.Archive.Tar             as Tar
 #endif
 import           Control.Exception.Safe
+import           Data.ByteString                ( ByteString )
+import           Data.CaseInsensitive           ( CI )
 import           Data.String.Interpolate
 import           Data.Text                      ( Text )
 import           Data.Versions
@@ -35,6 +37,8 @@ import           Text.PrettyPrint               hiding ( (<>) )
 import           Text.PrettyPrint.HughesPJClass hiding ( (<>) )
 import           URI.ByteString

+import qualified Data.Map.Strict               as M
+


    ------------------------
@@ -130,6 +134,13 @@ instance Pretty AlreadyInstalled where
  pPrint (AlreadyInstalled tool ver') =
    text [i|#{tool}-#{prettyShow ver'} is already installed|]

+-- | The Directory is supposed to be empty, but wasn't.
+data DirNotEmpty = DirNotEmpty {path :: FilePath}
+
+instance Pretty DirNotEmpty where
+  pPrint (DirNotEmpty path) = do
+    text [i|The directory was expected to be empty, but isn't: #{path}|]
+
 -- | The tool is not installed. Some operations rely on a tool
 -- to be installed (such as setting the current GHC version).
 data NotInstalled = NotInstalled Tool GHCTargetVersion
@@ -164,6 +175,16 @@ instance Pretty FileDoesNotExistError where
  pPrint (FileDoesNotExistError file) =
    text [i|File "#{file}" does not exist.|]

+-- | The file already exists
+-- (e.g. when we use isolated installs with the same path).
+-- (e.g. This is done to prevent any overwriting)
+data FileAlreadyExistsError = FileAlreadyExistsError FilePath
+  deriving Show
+
+instance Pretty FileAlreadyExistsError where
+  pPrint (FileAlreadyExistsError file) =
+    text [i|File "#{file}" Already exists.|]
+
 data TarDirDoesNotExist = TarDirDoesNotExist TarDir
  deriving Show

@@ -180,13 +201,29 @@ instance Pretty DigestError where
    text [i|Digest error: expected "#{expectedDigest}", but got "#{currentDigest}"|]

 -- | Unexpected HTTP status.
-data HTTPStatusError = HTTPStatusError Int
+data HTTPStatusError = HTTPStatusError Int (M.Map (CI ByteString) ByteString)
  deriving Show

 instance Pretty HTTPStatusError where
-  pPrint (HTTPStatusError status) =
+  pPrint (HTTPStatusError status _) =
    text [i|Unexpected HTTP status: #{status}|]

+-- | Malformed headers.
+data MalformedHeaders = MalformedHeaders Text
+  deriving Show
+
+instance Pretty MalformedHeaders where
+  pPrint (MalformedHeaders h) =
+    text [i|Headers are malformed: #{h}|]
+
+-- | Unexpected HTTP status.
+data HTTPNotModified = HTTPNotModified Text
+  deriving Show
+
+instance Pretty HTTPNotModified where
+  pPrint (HTTPNotModified etag) =
+    text [i|Remote resource not modifed, etag was: #{etag}|]
+
 -- | The 'Location' header was expected during a 3xx redirect, but not found.
 data NoLocationHeader = NoLocationHeader
  deriving Show
@@ -307,6 +344,15 @@ instance Pretty UnexpectedListLength where

 instance Exception UnexpectedListLength

+data NoUrlBase = NoUrlBase Text
+  deriving Show
+
+instance Pretty NoUrlBase where
+  pPrint (NoUrlBase url) =
+    text [i|Couldn't get a base filename from url #{url}|]
+
+instance Exception NoUrlBase
+


    ------------------------
--- a/lib/GHCup/Types.hs
+++ b/lib/GHCup/Types.hs
@@ -304,6 +304,41 @@ data UserSettings = UserSettings
 defaultUserSettings :: UserSettings
 defaultUserSettings = UserSettings Nothing Nothing Nothing Nothing Nothing Nothing Nothing Nothing

+fromSettings :: Settings -> Maybe KeyBindings -> UserSettings
+fromSettings Settings{..} Nothing =
+  UserSettings {
+      uCache = Just cache
+    , uNoVerify = Just noVerify
+    , uVerbose = Just verbose
+    , uKeepDirs = Just keepDirs
+    , uDownloader = Just downloader
+    , uNoNetwork = Just noNetwork
+    , uKeyBindings = Nothing
+    , uUrlSource = Just urlSource
+  }
+fromSettings Settings{..} (Just KeyBindings{..}) =
+  let ukb = UserKeyBindings
+            { kUp           = Just bUp        
+            , kDown         = Just bDown      
+            , kQuit         = Just bQuit      
+            , kInstall      = Just bInstall   
+            , kUninstall    = Just bUninstall 
+            , kSet          = Just bSet       
+            , kChangelog    = Just bChangelog 
+            , kShowAll      = Just bShowAllVersions
+            , kShowAllTools = Just bShowAllTools
+            }
+  in UserSettings {
+      uCache = Just cache
+    , uNoVerify = Just noVerify
+    , uVerbose = Just verbose
+    , uKeepDirs = Just keepDirs
+    , uDownloader = Just downloader
+    , uNoNetwork = Just noNetwork
+    , uKeyBindings = Just ukb
+    , uUrlSource = Just urlSource
+  }
+
 data UserKeyBindings = UserKeyBindings
  { kUp        :: Maybe Key
  , kDown      :: Maybe Key
--- a/lib/GHCup/Types/JSON.hs
+++ b/lib/GHCup/Types/JSON.hs
@@ -316,3 +316,6 @@ deriveJSON defaultOptions { sumEncoding = ObjectWithSingleField } ''URLSource
 deriveJSON defaultOptions { sumEncoding = ObjectWithSingleField } ''Key
 deriveJSON defaultOptions { fieldLabelModifier = \str' -> maybe str' T.unpack . T.stripPrefix (T.pack "k-") . T.pack . kebab $ str' } ''UserKeyBindings
 deriveJSON defaultOptions { fieldLabelModifier = \str' -> maybe str' T.unpack . T.stripPrefix (T.pack "u-") . T.pack . kebab $ str' } ''UserSettings
+
+deriveToJSON defaultOptions { fieldLabelModifier = kebab } ''Settings
+deriveToJSON defaultOptions { fieldLabelModifier = drop 2 . kebab } ''KeyBindings -- move under key-bindings key
--- a/lib/GHCup/Utils.hs
+++ b/lib/GHCup/Utils.hs
@@ -766,49 +766,22 @@ ghcToolFiles ver = do
  whenM (fmap not $ liftIO $ doesDirectoryExist ghcdir)
        (throwE (NotInstalled GHC ver))

-  files    <- liftIO $ listDirectory bindir
-  -- figure out the <ver> suffix, because this might not be `Version` for
-  -- alpha/rc releases, but x.y.a.somedate.
+  files <- liftIO (listDirectory bindir >>= filterM (doesFileExist . (bindir </>)))
+  pure (getUniqueTools . groupToolFiles . fmap (dropSuffix exeExt) $ files)

-  ghcIsHadrian    <- liftIO $ isHadrian bindir
-  onlyUnversioned <- case ghcIsHadrian of
-    Right () -> pure id
-    Left (fmap (dropSuffix exeExt) -> [ghc, ghc_ver])
-      | (Just symver) <- stripPrefix (ghc <> "-") ghc_ver
-      , not (null symver) -> pure $ filter (\x -> not $ symver `isInfixOf` x)
-    _ -> fail "Fatal: Could not find internal GHC version"
-
-  pure $ onlyUnversioned $ fmap (dropSuffix exeExt) files
 where
-  isNotAnyInfix xs t = foldr (\a b -> not (a `isInfixOf` t) && b) True xs
-    -- GHC is moving some builds to Hadrian for bindists,
-    -- which doesn't create versioned binaries.
-    -- https://gitlab.haskell.org/haskell/ghcup-hs/issues/31
-  isHadrian :: FilePath -- ^ ghcbin path
-            -> IO (Either [String] ()) -- ^ Right for Hadrian
-  isHadrian dir = do
-    -- Non-hadrian has e.g. ["ghc", "ghc-8.10.4"]
-    -- which also requires us to discover the internal version
-    -- to filter the correct tool files.
-    -- We can't use the symlink on windows, so we fall back to some
-    -- more complicated logic.
-    fs <- fmap
-         -- regex over-matches
-         (filter (isNotAnyInfix ["haddock", "ghc-pkg", "ghci"]))
-       $ liftIO $ findFiles
-      dir
-      (makeRegexOpts compExtended
-                     execBlank
-                     -- for cross, this won't be "ghc", but e.g.
-                     -- "armv7-unknown-linux-gnueabihf-ghc"
-                     ([s|^([a-zA-Z0-9_-]*[a-zA-Z0-9_]-)?ghc.*$|] :: ByteString)
-      )
-    if | length fs == 1 -> pure $ Right ()        -- hadrian
-       | length fs == 2 -> pure $ Left
-                              (sortOn length fs)  -- legacy make, result should
-                                                  -- be ["ghc", "ghc-8.10.4"]
-       | otherwise      -> fail "isHadrian failed!"

+  groupToolFiles :: [FilePath] -> [[(FilePath, String)]]
+  groupToolFiles = groupBy (\(a, _) (b, _) -> a == b) . fmap (splitOnPVP "-")
+
+  getUniqueTools :: [[(FilePath, String)]] -> [String]
+  getUniqueTools = filter (isNotAnyInfix blackListedTools) . nub . fmap fst . filter ((== "") . snd) . concat
+
+  blackListedTools :: [String]
+  blackListedTools = ["haddock-ghc"]
+
+  isNotAnyInfix :: [String] -> String -> Bool
+  isNotAnyInfix xs t = foldr (\a b -> not (a `isInfixOf` t) && b) True xs


 -- | This file, when residing in @~\/.ghcup\/ghc\/\<ver\>\/@ signals that
--- a/lib/GHCup/Utils/File/Windows.hs
+++ b/lib/GHCup/Utils/File/Windows.hs
@@ -209,6 +209,20 @@ exec exe args chdir env = do
  pure $ toProcessError exe args exit_code


+-- | Thin wrapper around `executeFile`.
+execShell :: MonadIO m
+          => FilePath       -- ^ thing to execute
+          -> [FilePath]     -- ^ args for the thing
+          -> Maybe FilePath   -- ^ optionally chdir into this
+          -> Maybe [(String, String)] -- ^ optional environment
+          -> m (Either ProcessError ())
+execShell exe args chdir env = do
+  let cmd = exe <> " " <> concatMap (' ':) args
+  cp <- createProcessWithMingwPath ((shell cmd) { cwd = chdir, env = env })
+  exit_code <- liftIO $ withCreateProcess cp $ \_ _ _ p -> waitForProcess p
+  pure $ toProcessError cmd [] exit_code
+
+
 chmod_755 :: MonadIO m => FilePath -> m ()
 chmod_755 fp =
  let perm = setOwnerWritable True emptyPermissions
--- a/lib/GHCup/Utils/Prelude.hs
+++ b/lib/GHCup/Utils/Prelude.hs
@@ -31,7 +31,7 @@ import           Control.Monad.IO.Class
 import           Control.Monad.Reader
 import           Data.Bifunctor
 import           Data.ByteString                ( ByteString )
-import           Data.List                      ( nub )
+import           Data.List                      ( nub, intercalate )
 import           Data.Foldable
 import           Data.String
 import           Data.Text                      ( Text )
@@ -55,6 +55,7 @@ import           GHC.IO.Exception
 import qualified Data.ByteString               as B
 import qualified Data.ByteString.Lazy          as L
 import qualified Data.Strict.Maybe             as S
+import qualified Data.List.Split               as Split
 import qualified Data.Text                     as T
 import qualified Data.Text.Encoding            as E
 import qualified Data.Text.Encoding.Error      as E
@@ -410,12 +411,7 @@ rmPathForcibly :: ( MonadIO m
               -> m ()
 rmPathForcibly fp =
 #if defined(IS_WINDOWS)
-  recovering (fullJitterBackoff 25000 <> limitRetries 10)
-    [\_ -> Handler (\e -> pure $ isPermissionError e)
-    ,\_ -> Handler (\e -> pure (ioeGetErrorType e == InappropriateType))
-    ,\_ -> Handler (\e -> pure (ioeGetErrorType e == UnsatisfiedConstraints))
-    ]
-    (\_ -> liftIO $ removePathForcibly fp)
+  recover (liftIO $ removePathForcibly fp)
 #else
  liftIO $ removePathForcibly fp
 #endif
@@ -426,12 +422,7 @@ rmDirectory :: (MonadIO m, MonadMask m)
            -> m ()
 rmDirectory fp =
 #if defined(IS_WINDOWS)
-  recovering (fullJitterBackoff 25000 <> limitRetries 10)
-    [\_ -> Handler (\e -> pure $ isPermissionError e)
-    ,\_ -> Handler (\e -> pure (ioeGetErrorType e == UnsatisfiedConstraints))
-    ,\_ -> Handler (\e -> pure (ioeGetErrorType e == InappropriateType))
-    ]
-    (\_ -> liftIO $ removeDirectory fp)
+  recover (liftIO $ removeDirectory fp)
 #else
  liftIO $ removeDirectory fp
 #endif
@@ -469,12 +460,7 @@ rmFile :: ( MonadIO m
      -> m ()
 rmFile fp =
 #if defined(IS_WINDOWS)
-  recovering (fullJitterBackoff 25000 <> limitRetries 10)
-    [\_ -> Handler (\e -> pure $ isPermissionError e)
-    ,\_ -> Handler (\e -> pure (ioeGetErrorType e == InappropriateType))
-    ,\_ -> Handler (\e -> pure (ioeGetErrorType e == UnsatisfiedConstraints))
-    ]
-    (\_ -> liftIO $ removeFile fp)
+  recover (liftIO $ removeFile fp)
 #else
  liftIO $ removeFile fp
 #endif
@@ -485,12 +471,7 @@ rmDirectoryLink :: (MonadIO m, MonadMask m, MonadReader env m, HasDirs env)
                -> m ()
 rmDirectoryLink fp = 
 #if defined(IS_WINDOWS)
-  recovering (fullJitterBackoff 25000 <> limitRetries 10)
-    [\_ -> Handler (\e -> pure $ isPermissionError e)
-    ,\_ -> Handler (\e -> pure (ioeGetErrorType e == InappropriateType))
-    ,\_ -> Handler (\e -> pure (ioeGetErrorType e == UnsatisfiedConstraints))
-    ]
-    (\_ -> liftIO $ removeDirectoryLink fp)
+  recover (liftIO $ removeDirectoryLink fp)
 #else
  liftIO $ removeDirectoryLink fp
 #endif
@@ -525,8 +506,32 @@ stripNewline s
  | otherwise            = head s : stripNewline (tail s)


+-- | Strip @\\r@ and @\\n@ from 'ByteString's
+stripNewline' :: T.Text -> T.Text
+stripNewline' s
+  | T.null s               = mempty
+  | T.head s `elem` "\n\r" = stripNewline' (T.tail s)
+  | otherwise              = T.singleton (T.head s) <> stripNewline' (T.tail s)
+
+
 isNewLine :: Word8 -> Bool
 isNewLine w
  | w == _lf = True
  | w == _cr = True
  | otherwise = False
+
+
+-- | Split on a PVP suffix.
+--
+-- >>> splitOnPVP "-" "ghc-iserv-dyn-9.3.20210706" == ("ghc-iserv-dyn", "9.3.20210706")
+-- >>> splitOnPVP "-" "ghc-iserv-dyn"              == ("ghc-iserv-dyn", "")
+splitOnPVP :: String -> String -> (String, String)
+splitOnPVP c s = case Split.splitOn c s of
+  []  -> def
+  [_] -> def
+  xs
+    | let l = last xs
+    , (Right _) <- pvp (T.pack l) -> (intercalate c (init xs), l)
+    | otherwise -> def
+ where
+  def = (s, "")
--- a/lib/GHCup/Version.hs
+++ b/lib/GHCup/Version.hs
@@ -25,7 +25,7 @@ import qualified Data.Text                     as T

 -- | This reflects the API version of the YAML.
 ghcupURL :: URI
-ghcupURL = [uri|https://www.haskell.org/ghcup/data/ghcup-0.0.5.yaml|]
+ghcupURL = [uri|https://www.haskell.org/ghcup/data/ghcup-0.0.6.yaml|]

 -- | The current ghcup version.
 ghcUpVer :: PVP
--- a/www/Discord-Logo-Black.svg
+++ b/www/Discord-Logo-Black.svg
@@ -0,0 +1,10 @@
+<svg width="71" height="55" viewBox="0 0 71 55" fill="none" xmlns="http://www.w3.org/2000/svg">
+<g clip-path="url(#clip0)">
+<path d="M60.1045 4.8978C55.5792 2.8214 50.7265 1.2916 45.6527 0.41542C45.5603 0.39851 45.468 0.440769 45.4204 0.525289C44.7963 1.6353 44.105 3.0834 43.6209 4.2216C38.1637 3.4046 32.7345 3.4046 27.3892 4.2216C26.905 3.0581 26.1886 1.6353 25.5617 0.525289C25.5141 0.443589 25.4218 0.40133 25.3294 0.41542C20.2584 1.2888 15.4057 2.8186 10.8776 4.8978C10.8384 4.9147 10.8048 4.9429 10.7825 4.9795C1.57795 18.7309 -0.943561 32.1443 0.293408 45.3914C0.299005 45.4562 0.335386 45.5182 0.385761 45.5576C6.45866 50.0174 12.3413 52.7249 18.1147 54.5195C18.2071 54.5477 18.305 54.5139 18.3638 54.4378C19.7295 52.5728 20.9469 50.6063 21.9907 48.5383C22.0523 48.4172 21.9935 48.2735 21.8676 48.2256C19.9366 47.4931 18.0979 46.6 16.3292 45.5858C16.1893 45.5041 16.1781 45.304 16.3068 45.2082C16.679 44.9293 17.0513 44.6391 17.4067 44.3461C17.471 44.2926 17.5606 44.2813 17.6362 44.3151C29.2558 49.6202 41.8354 49.6202 53.3179 44.3151C53.3935 44.2785 53.4831 44.2898 53.5502 44.3433C53.9057 44.6363 54.2779 44.9293 54.6529 45.2082C54.7816 45.304 54.7732 45.5041 54.6333 45.5858C52.8646 46.6197 51.0259 47.4931 49.0921 48.2228C48.9662 48.2707 48.9102 48.4172 48.9718 48.5383C50.038 50.6034 51.2554 52.5699 52.5959 54.435C52.6519 54.5139 52.7526 54.5477 52.845 54.5195C58.6464 52.7249 64.529 50.0174 70.6019 45.5576C70.6551 45.5182 70.6887 45.459 70.6943 45.3942C72.1747 30.0791 68.2147 16.7757 60.1968 4.9823C60.1772 4.9429 60.1437 4.9147 60.1045 4.8978ZM23.7259 37.3253C20.2276 37.3253 17.3451 34.1136 17.3451 30.1693C17.3451 26.225 20.1717 23.0133 23.7259 23.0133C27.308 23.0133 30.1626 26.2532 30.1066 30.1693C30.1066 34.1136 27.28 37.3253 23.7259 37.3253ZM47.3178 37.3253C43.8196 37.3253 40.9371 34.1136 40.9371 30.1693C40.9371 26.225 43.7636 23.0133 47.3178 23.0133C50.9 23.0133 53.7545 26.2532 53.6986 30.1693C53.6986 34.1136 50.9 37.3253 47.3178 37.3253Z" fill="#23272A"/>
+</g>
+<defs>
+<clipPath id="clip0">
+<rect width="71" height="55" fill="white"/>
+</clipPath>
+</defs>
+</svg>
--- a/www/Matrix_logo.svg
+++ b/www/Matrix_logo.svg
@@ -0,0 +1,7 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<svg version="1.1" viewBox="0 0 75 32" xmlns="http://www.w3.org/2000/svg" xmlns:cc="http://creativecommons.org/ns#" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#">
+<title>Matrix (protocol) logo</title>
+ <g fill="#040404">
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+</svg>
--- a/www/Octicons-bug.svg
+++ b/www/Octicons-bug.svg
@@ -0,0 +1,36 @@
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--- a/www/index.html
+++ b/www/index.html
@@ -128,19 +128,22 @@
        <div>
          <p>
            If you are running Windows,<br/>run the following in a powershell session (as a non-admin user).
-			<div class="command-button"><pre><span class='ghcup-command'>Set-ExecutionPolicy Bypass -Scope Process -Force;[System.Net.ServicePointManager]::SecurityProtocol = [System.Net.ServicePointManager]::SecurityProtocol -bor 3072;Invoke-Command -ScriptBlock ([ScriptBlock]::Create((Invoke-WebRequest https://www.haskell.org/ghcup/sh/bootstrap-haskell.ps1 -UseBasicParsing))) -ArgumentList $false</span></span></pre><button class="tooltip" onclick="copyToClipboardPowershell()"><img src="copy.svg" alt="" /><span class="tooltiptext">Copy to clipboard</span></button></div>
+			<div class="command-button"><pre><span class='ghcup-command'>Set-ExecutionPolicy Bypass -Scope Process -Force;[System.Net.ServicePointManager]::SecurityProtocol = [System.Net.ServicePointManager]::SecurityProtocol -bor 3072;Invoke-Command -ScriptBlock ([ScriptBlock]::Create((Invoke-WebRequest https://www.haskell.org/ghcup/sh/bootstrap-haskell.ps1 -UseBasicParsing))) -ArgumentList $true</span></span></pre><button class="tooltip" onclick="copyToClipboardPowershell()"><img src="copy.svg" alt="" /><span class="tooltiptext">Copy to clipboard</span></button>
+			</div>
+				<p class="other-help">If you want to run a non-interactive installation, change <span class='code'>$true</span> to <span class='code'>$false</span> at the end of the script.</p>
+			</div>
          </p>
        </div>

      </div>

      <p>
-        Need help? Ask on <a href="https://kiwiirc.com/nextclient/irc.libera.chat/#haskell-ghcup">#haskell-ghcup</a>, <a href="https://kiwiirc.com/nextclient/irc.libera.chat/#haskell">#haskell</a> or <a href="https://gitlab.haskell.org/haskell/ghcup-hs/issues">report a bug</a>.
+	  Need help? Ask on <a href="https://kiwiirc.com/nextclient/irc.libera.chat/?nick=Guest%7C?#haskell,#haskell-ghcup"><img src="irc.svg" height="18px" alt="" />IRC</a>, <a href="https://discord.gg/pKYf3zDQU7"><img src="Discord-Logo-Black.svg" height="18px" alt="" />Discord</a>, <a href="https://app.element.io/#/room/#haskell-tooling:matrix.org"><img src="Matrix_logo.svg" height="25px" alt="" style="top:5px;position:relative;" /></a> or <a href="https://gitlab.haskell.org/haskell/ghcup-hs/issues">report a bug <img src="Octicons-bug.svg" height="18px" alt="" /></a>.
      </p>

      <p id="about">
        <img src="haskell-logo.svg" alt="" />
-        ghcup is a haskell.org hosted project.
+        ghcup is a haskell.org supported project.
        <br/>
        <a href="https://www.haskell.org/downloads/">other installation options</a>
        &nbsp;&middot;&nbsp;
--- a/www/irc.svg
+++ b/www/irc.svg
@@ -0,0 +1,38 @@
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Author	SHA1	Message	Date
Julian Ospald	b86e2a1d5b	Add GHC-9.2.0.20210821 rc1	2021-08-23 13:16:18 +02:00
Julian Ospald	099a6b9dcd	Merge branch 'fixes'	2021-08-21 14:46:43 +02:00
Julian Ospald	3b13624117	Clean up CI	2021-08-21 14:34:47 +02:00
Julian Ospald	fad1efcefa	Fix wrong libffi dependency version for Debian 11 (bullseye) Fixes #209	2021-08-21 14:28:53 +02:00
Julian Ospald	1701b8a2f4	Fix bootstrap-haskell prompts when no shell is detected	2021-08-21 14:28:31 +02:00
Julian Ospald	608ee07940	Merge remote-tracking branch 'origin/merge-requests/146'	2021-08-21 09:28:56 +02:00
Arjun Kathuria	a0c2a5ccec	Adds isolated installs documentation in readme	2021-08-16 22:08:44 +05:30
Julian Ospald	cd41d3af97	Merge branch 'fix-CI'	2021-08-16 14:18:58 +02:00
Julian Ospald	b5aafdee61	Fix CI	2021-08-16 12:57:05 +02:00
Julian Ospald	9d9e4bb44e	Add GHC-8.10.6	2021-08-14 17:01:27 +02:00
Julian Ospald	c708283547	Merge branch 'issue-208'	2021-08-14 15:13:47 +02:00
Julian Ospald	a4ddf95c8d	Check for chocolatey during windows bootstrap Fixes #208	2021-08-14 14:44:00 +02:00
Julian Ospald	ddbb396bf3	Add discord logo Hopefully this is all legal :o	2021-08-12 18:03:33 +02:00
Julian Ospald	e2a7c320ac	Fix matrix link	2021-08-12 13:33:17 +02:00
Julian Ospald	06f998fa5e	Update README badges	2021-08-12 13:31:28 +02:00
Julian Ospald	c48c73d34d	Merge remote-tracking branch 'origin/pr/5'	2021-08-12 13:13:31 +02:00
Julian Ospald	cfb6ab31ab	Update website	2021-08-12 13:08:52 +02:00
The Gitter Badger	eac15541e8	Add Gitter badge	2021-08-12 09:28:17 +00:00
Julian Ospald	984acebff8	Fix metadata files	2021-08-12 11:12:55 +02:00
Julian Ospald	4cf2d125dd	Update metadata to 0.1.16.2	2021-08-11 20:01:37 +02:00
Julian Ospald	6701093c3b	Bump version to 0.1.16.2	2021-08-11 16:30:01 +02:00
Julian Ospald	e9fdc073c6	Fix --flavor	2021-08-11 16:19:52 +02:00
Julian Ospald	57c791106b	Fixup rest of the PR	2021-08-11 16:19:31 +02:00
Julian Ospald	fcba151fad	Merge remote-tracking branch 'origin/merge-requests/134'	2021-08-11 14:20:04 +02:00
Julian Ospald	3b24f503d1	Fixup rest of the PR	2021-08-11 13:54:02 +02:00
Julian Ospald	bd18fd9aa1	Merge remote-tracking branch 'origin/merge-requests/127'	2021-08-11 12:28:48 +02:00
Arjun Kathuria	c2c5625685	implements checking if file already exists for Cabal installs	2021-08-11 10:33:08 +05:30
Arjun Kathuria	ce6fb0bb1e	Adds new Error type `FileAlreadyExistsError`	2021-08-11 10:28:30 +05:30
Arjun Kathuria	dcfb3afdad	Revert "implements isolated install sanity-checking for Cabal installs" This reverts commit `300cfd3ba6`.	2021-08-11 09:46:42 +05:30
Julian Ospald	50c91345e8	Merge branch 'windows-autoconf'	2021-08-10 17:08:43 +02:00
Julian Ospald	af3ecae792	Install autoconf in msys2 wrt #200	2021-08-10 16:58:37 +02:00
Arjun Kathuria	300cfd3ba6	implements isolated install sanity-checking for Cabal installs	2021-08-10 20:14:46 +05:30
Arjun Kathuria	bb430fa0b7	Adds the sanity check function for isolated installs	2021-08-10 20:12:14 +05:30
Arjun Kathuria	80fa7965a4	Adds new Error type `IsolatedDirNotEmpty`	2021-08-10 20:11:32 +05:30
Julian Ospald	9975a2d4ba	Merge branch 'fix-install'	2021-08-10 16:39:46 +02:00
Arjun Kathuria	d1735bc446	adds toolchainSanityChecks for isolated installs too in `installGHCBindist` function.	2021-08-10 19:53:41 +05:30
Julian Ospald	dbf1d6f420	Fix unneeded dist files being installed along with GHC	2021-08-10 15:58:40 +02:00
Julian Ospald	0a0fbd0cb6	Merge branch 'fix-metadata-download'	2021-08-07 19:26:26 +02:00
Julian Ospald	f13f53b910	Merge branch 'throwM'	2021-08-07 19:20:00 +02:00
Julian Ospald	6dfc04a9f6	Fix metadata file read in --offline mode	2021-08-07 18:31:41 +02:00
Julian Ospald	72133d0002	Rather skip copying to cache dir if scheme is file://	2021-08-07 10:24:08 +02:00
Julian Ospald	6e07e9e56b	Skip copying metadata if source and destination match	2021-08-07 09:55:45 +02:00
Julian Ospald	e903aeb555	Skip cached metadata when url starts with file://	2021-08-07 09:54:26 +02:00
Julian Ospald	2792f6f4b6	Fix error handling when we can't find a filename	2021-08-06 19:45:59 +02:00
Arjun Kathuria	80eb72ce49	Merge branch 'smash-1' of gitlab.haskell.org:arjun/ghcup-hs into smash-1	2021-08-04 16:09:48 +05:30
Arjun Kathuria	2c6d0382cf	adds isolate install feature to compiled ghc command	2021-08-04 16:08:12 +05:30
Arjun Kathuria	e1bec789b0	updates Bindist functions as per https://gitlab.haskell.org/haskell/ghcup-hs/-/merge_requests/127#note_366702	2021-08-03 18:08:54 +05:30
Arjun Kathuria	5683493cae	rename some auxiliary functions to their "unpacked" versions	2021-08-03 18:08:54 +05:30
Arjun Kathuria	ae5e213b59	deletes `installStackBinIsolated` function	2021-08-03 18:08:54 +05:30
Arjun Kathuria	911089f334	updates usages of new `installStackBin` across files	2021-08-03 18:08:54 +05:30
Arjun Kathuria	6b89646c1e	update `installStackBindist` to take a "Maybe FilePath" argument for isolated installs	2021-08-03 18:08:54 +05:30
Arjun Kathuria	960d5ce79f	deletes `installHLSBinIsolated` function	2021-08-03 18:08:54 +05:30
Arjun Kathuria	90ed0895d6	updates usages of `installHLSBin` across files	2021-08-03 18:08:54 +05:30
Arjun Kathuria	7471f4f4dc	update `installHLSBindist` to take a "Maybe FilePath" argument for isolated installs	2021-08-03 18:08:54 +05:30
Arjun Kathuria	781cf8eed5	Delete installCabalBinIsolated function.	2021-08-03 18:08:54 +05:30
Arjun Kathuria	236da31af6	updates usages of new `installCabalBindist` across files.	2021-08-03 18:08:54 +05:30
Arjun Kathuria	1f760af880	update `installCabalBindist` to take a "Maybe FilePath" argument for isolated installs	2021-08-03 18:08:54 +05:30
Arjun Kathuria	62d03b776b	remove installGHCBinIsolated function.	2021-08-03 18:08:54 +05:30
Arjun Kathuria	37ea18a0d8	updates usages of new installGHCBindist and related installGHCBin	2021-08-03 18:08:54 +05:30
Arjun Kathuria	083dc59a8f	update `installGhcBindist` to take a "Maybe FilePath" to work with isolated installs	2021-08-03 18:08:54 +05:30
Arjun Kathuria	a45d069cad	Adds a log to notify where the isolated ghc is being installed by the tool	2021-08-03 18:08:54 +05:30
Arjun Kathuria	fdbcd4fafd	Adds isolated installs to Stack install	2021-08-03 18:08:54 +05:30
Arjun Kathuria	f3c1c925ed	updates installStack' usage in `installStackBindist` function	2021-08-03 18:08:54 +05:30
Arjun Kathuria	8f6a7ba39c	factor out installStack' function	2021-08-03 18:08:54 +05:30
Arjun Kathuria	f212eb4570	Adds isolated install to HLS installs	2021-08-03 18:08:54 +05:30
Arjun Kathuria	0d118e2fe1	update installHLS' usage in `installHLSBindist`	2021-08-03 18:08:54 +05:30
Arjun Kathuria	c0f46ef81f	Factor out installHLS'	2021-08-03 18:08:54 +05:30
Arjun Kathuria	476513b0a7	Adds isolate install functionality to 'Cabal' tool installs	2021-08-03 18:08:54 +05:30
Arjun Kathuria	9a511669a8	use the new factored out installCabal' in `installCabalBindist` function	2021-08-03 18:08:54 +05:30
Arjun Kathuria	a16a25a3cd	factor out installCabal' from `installCabalBindist`, to be shared with `installCabalBinIsolated` function	2021-08-03 18:08:54 +05:30
Arjun Kathuria	8666fcd120	adds rudimentary isolate capability to ghcup install ghc command	2021-08-03 18:08:54 +05:30
Arjun Kathuria	521ab0aedb	adds basic --isolate option structure for install commands	2021-08-03 18:08:54 +05:30
vglfr	1cfff674b7	Implement config CLI MVP	2021-08-03 09:09:47 +03:00
Julian Ospald	88d1d19f55	Merge branch 'bump-bs-ver'	2021-07-31 16:38:12 +02:00
Julian Ospald	0fb1da5c3a	Bump ghc version in bootstrap-haskell	2021-07-31 16:23:01 +02:00
Julian Ospald	b32f88e9a6	Merge branch 'update-hls-1.3.0'	2021-07-31 14:44:16 +02:00
Julian Ospald	9d2421fac5	Update to HLS 1.3.0	2021-07-31 13:30:29 +02:00
Julian Ospald	043e288fbf	Add tipps and tricks section	2021-07-30 20:06:19 +02:00
Julian Ospald	32e34876e2	Update	2021-07-29 22:45:48 +02:00
Julian Ospald	f12a2b3821	Update README	2021-07-29 22:40:35 +02:00
Julian Ospald	844b4decab	Update FAQ	2021-07-29 22:35:52 +02:00
Julian Ospald	53ca60596d	Fix nuclear order	2021-07-29 11:51:47 +02:00
Julian Ospald	2d2894b0f4	Bump metadata	2021-07-29 10:50:07 +02:00
Julian Ospald	21d30cd8ce	Fix GHCup showing up twice in list	2021-07-28 22:48:28 +02:00
Julian Ospald	b38a569124	Bump to 0.1.16.1	2021-07-28 22:36:59 +02:00
Julian Ospald	810607e84f	Update yamls	2021-07-28 22:31:56 +02:00
Julian Ospald	442ddfd4e4	Bump ghcup metadata, because new GHC versions may have different bin/ layout	2021-07-28 20:08:20 +02:00
Julian Ospald	096103e65a	Refreeze	2021-07-28 18:42:57 +02:00
Julian Ospald	60a56c337c	Merge branch 'travis'	2021-07-28 18:42:35 +02:00
Julian Ospald	11c1b2cc6c	Re-add travis	2021-07-28 18:02:34 +02:00
Julian Ospald	45db3bd913	Update README	2021-07-28 11:07:53 +02:00
Julian Ospald	6d76561340	Update CHANGELOG for 0.1.16	2021-07-27 23:34:32 +02:00
Julian Ospald	00caeba067	Merge branch 'fix-list-tools'	2021-07-27 23:16:18 +02:00
Julian Ospald	5a34191b88	Fix listTools to always show currently installed GHCup	2021-07-27 22:33:35 +02:00
Julian Ospald	85003900d7	Improve HLS post-install formatting	2021-07-27 20:58:39 +02:00
Julian Ospald	0c666a6bbe	Fix upgrade subcommand running appstate twice	2021-07-27 20:57:51 +02:00
Julian Ospald	e4e52ebf6b	Bump to 0.1.16	2021-07-27 20:39:12 +02:00
Julian Ospald	4512468108	Also upload dist-newstyle/cache on failure	2021-07-27 10:39:55 +02:00
Julian Ospald	d3e3ebd63f	Merge branch 'fix-ghcToolFiles'	2021-07-26 21:25:00 +02:00
Julian Ospald	ce616d3eb3	Improve bootstrap-haskell.ps1	2021-07-26 18:14:07 +02:00
Julian Ospald	5837e04e6e	Cleanup	2021-07-26 18:13:57 +02:00
Julian Ospald	95ca79f3f8	Turn leftover files into logError	2021-07-26 18:13:41 +02:00
Julian Ospald	706fe1ffcc	Don't do update checks for all commands	2021-07-26 18:13:20 +02:00
Julian Ospald	2774f026e8	Merge branch 'issue-150'	2021-07-26 17:44:37 +02:00
Julian Ospald	07604a2eb5	Merge branch 'issue-193'	2021-07-26 17:39:13 +02:00
Arjun Kathuria	03d77f5006	updates Bindist functions as per https://gitlab.haskell.org/haskell/ghcup-hs/-/merge_requests/127#note_366702	2021-07-26 11:49:52 +05:30
Julian Ospald	fdf45e0fe6	Do etags hashing wrt #193	2021-07-25 23:15:59 +02:00
Julian Ospald	1dc9ad7a57	Merge branch 'www-false'	2021-07-25 19:56:56 +02:00
Julian Ospald	cc51d7b454	Merge branch 'add-binutils-gold-for-alpine-pkgs'	2021-07-25 19:56:24 +02:00
Julian Ospald	c439693a8f	Fix "display all supported installers" page	2021-07-25 19:10:02 +02:00
Julian Ospald	af8c097092	Add binutils gold for alpine pkgs	2021-07-25 19:06:22 +02:00
Arjun Kathuria	71e6dbfdca	rename some auxiliary functions to their "unpacked" versions	2021-07-25 22:34:53 +05:30
Arjun Kathuria	692cd1616b	deletes `installStackBinIsolated` function	2021-07-25 22:25:25 +05:30
Arjun Kathuria	4e3dbea5d0	updates usages of new `installStackBin` across files	2021-07-25 22:24:38 +05:30
Arjun Kathuria	fd2add78bd	update `installStackBindist` to take a "Maybe FilePath" argument for isolated installs	2021-07-25 22:23:58 +05:30
Arjun Kathuria	e9da8ab439	deletes `installHLSBinIsolated` function	2021-07-25 22:10:43 +05:30
Arjun Kathuria	9c22ba9d45	updates usages of `installHLSBin` across files	2021-07-25 22:10:10 +05:30
Arjun Kathuria	e5d3080b54	update `installHLSBindist` to take a "Maybe FilePath" argument for isolated installs	2021-07-25 22:09:54 +05:30
Arjun Kathuria	5995a8b592	Delete installCabalBinIsolated function.	2021-07-25 22:09:54 +05:30
Arjun Kathuria	bc6d006c57	updates usages of new `installCabalBindist` across files.	2021-07-25 22:09:54 +05:30
Arjun Kathuria	b148d8e2e7	update `installCabalBindist` to take a "Maybe FilePath" argument for isolated installs	2021-07-25 21:20:42 +05:30
Arjun Kathuria	4f7d41a8cc	remove installGHCBinIsolated function.	2021-07-25 13:39:44 +05:30
Arjun Kathuria	5efe2e5f7a	updates usages of new installGHCBindist and related installGHCBin	2021-07-25 13:38:32 +05:30
Arjun Kathuria	338f5f309d	update `installGhcBindist` to take a "Maybe FilePath" to work with isolated installs	2021-07-25 13:35:41 +05:30
Julian Ospald	9639e695e2	Unhide stack	2021-07-23 16:13:07 +02:00
Julian Ospald	d2a2bde321	Merge branch 'mlang-cursor'	2021-07-23 14:46:06 +02:00
Arjun Kathuria	ba51cbad6f	Adds a log to notify where the isolated ghc is being installed by the tool	2021-07-23 16:51:50 +05:30
Arjun Kathuria	511272e86d	Adds isolated installs to Stack install	2021-07-23 16:46:11 +05:30
Arjun Kathuria	873f75da9f	updates installStack' usage in `installStackBindist` function	2021-07-23 16:44:40 +05:30
Arjun Kathuria	42d4a66493	factor out installStack' function	2021-07-23 16:43:43 +05:30
Arjun Kathuria	9a79af6fd2	Adds isolated install to HLS installs	2021-07-23 16:25:01 +05:30
Arjun Kathuria	63f10a1871	update installHLS' usage in `installHLSBindist`	2021-07-23 16:23:52 +05:30
Arjun Kathuria	9686ee9826	Factor out installHLS'	2021-07-23 16:23:03 +05:30
Arjun Kathuria	4729364e99	Adds isolate install functionality to 'Cabal' tool installs	2021-07-23 15:57:42 +05:30
Arjun Kathuria	91d982c7b2	use the new factored out installCabal' in `installCabalBindist` function	2021-07-23 15:56:03 +05:30
Arjun Kathuria	8b7c22440e	factor out installCabal' from `installCabalBindist`, to be shared with `installCabalBinIsolated` function	2021-07-23 15:52:28 +05:30
Arjun Kathuria	9b3d55a095	adds rudimentary isolate capability to ghcup install ghc command	2021-07-22 19:32:56 +05:30
Arjun Kathuria	e2daf5381c	adds basic --isolate option structure for install commands	2021-07-20 22:05:01 +05:30
Julian Ospald	928f4a97de	Fix ghcToolFiles for upcoming GHC build system changes Also see: https://gitlab.haskell.org/ghc/ghc/-/issues/20074#note_363720	2021-07-10 21:43:37 +02:00
Julian Ospald	abbe51614d	Improve uninstallation on windows wrt #150	2021-07-07 23:19:50 +02:00