HLint is triggered

[philderbeast]

I ran hlint over unliftio and unliftio-core and found:

Warnings currently triggered by your code

- [ ] Avoid lambda, 2 hints
- [ ] Avoid lambda using `infix`, 3 hints
- [ ] Eta reduce, 1 hint
- [ ] Move brackets to avoid $, 14 hints
- [ ] Redundant bracket, 34 hints
- [ ] Replace case with maybe, 1 hint
- [ ] Unused LANGUAGE pragma, 12 hints
- [ ] Use <$>, 2 hints
- [ ] Use asum, 4 hints
- [ ] Use camelCase, 19 hints
- [ ] Use const, 4 hints
- [ ] Use even, 3 hints
- [ ] Use fewer imports, 1 hint
- [ ] Use fmap, 13 hints
- [ ] Use lambda-case, 1 hint
- [ ] Use newTVarIO, 3 hints
- [ ] Use readTVarIO, 8 hints
- [ ] Use void, 1 hint
- [ ] Use when, 2 hints

Which of these do we care about?