Let's derive HTTP clients from types
summary
Claim: you can derive your HTTP client function from a single type. Implementation details: represent endpoints as literal singleton types, use shapeless witness and HList to build a type‑level API, then run recursive implicit resolution (lazy implicits) to fold into a request structure. Result: a derived function for HTTP4s returning IO[List[User]] that actually works. Caveats: compilation can blow up — uploader reports exponential compile times up to hours — code and a library exist but need performance tuning.
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chapters (14)
- 0:00Intro
- 2:15Summary
- 4:01Benefits and Cost
- 5:48About me
- 12:00API type
- 19:33Derivation
- 29:45Implicit Resolution
- 31:02Data Collection
- 31:58Return Case
- 34:41Putting it all together
- 36:38Derived
- 38:28Two takeaways
- 39:21A shameless plug
- 40:58Questions
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