2.2 KiB
HACKING
Design decisions
Using Excepts as a beefed up ExceptT
This is an open variant, similar to plucky or oops and allows us to combine different error types. Maybe it is too much and it's a little bit unergonomic at times. If it really hurts maintenance, it will be removed. It was more of an experiment.
No use of filepath or directory
Filepath and directory have two fundamental problems: 1. they use String as filepath (see AFPP as to why this is wrong) and 2. they try very hard to be cross-platform at the expense of low-level correctness. Instead, we use the hpath libraries for file and filepath related stuff, which also gives us stronger filepath types.
No use of haskell-TLS
I consider haskell-TLS an interesting experiment, but not a battle-tested and peer-reviewed crypto implementation. There is little to no research about what the intricacies of using haskell for low-level crypto are and how vulnerable such binaries are. Instead, we use either curl the binary (for FreeBSD and mac) or http-io-streams, which works with OpenSSL bindings.
Optics instead of lens
They're a little safer (less Monoid weirdness with view) and have better error messages. Consider the following wit lens
> view (_Just . to (++ "abc")) Nothing
""
vs optics
view (_Just % to (++ "abc")) Nothing
<interactive>:2:1: error:
• An_AffineFold cannot be used as A_Getter
• In the expression: view (_Just % to (++ "abc")) Nothing
In an equation for ‘it’: it = view (_Just % to (++ "abc")) Nothing
Strict and StrictData on by default
Kazu Yamamoto explained it in his PR very well. I like to agree with him. The instances where we need non-strict behavior, we annotate it.
Code style and formatting
- Brittany
- mtl-style preferred
- no overly pointfree style