Thread by @graninas

I'm learning ZIO (by @jdegoes), and I can say this framework has so much in common with my frameworks.

ZIO is based on Free monads.

All my frameworks (Node, Hydra, frameworks at @juspay) are based on Free monads.

1/

ZIO and Hydra programs are values which can be interpreted due to the Free monadic nature. Free monads is the best approach to separate interface and implementation. Free monadic programs are simple, maintainable and testable.

2/

In ZIO, there is a notion of Runtime. It’s a place for keeping resources, such as a thread pool.

Not by chance, my frameworks share the same design. There is the Runtime structure which hides a lot of implementation details about the internal stuff.

3/

By default, ZIO provides: Console, System, Clock, Random, Scheduler, and on the JVM, Blocking.

By default, Hydra provides: CLI, Random, Logging, STM-like state, Threads, (scheduler in the form of the Haskell STM runtime), SQL DB, KV DB, HTTP client API.

4/

I had a hard time debating with haskellers why Free monads are the most beneficial approach to build real world applications.

I believe it wasn’t easy for @jdegoes to convince the Scala community that ZIO is a great technology.

5/

Number of contributors to ZIO: more than 300.

Number of contributors to Hydra: 4.

(Number of contributors to Juspay’s frameworks is greater than 20)

6/

Number of commercial ZIO clients: more than 15. And increasing.

Number of commercial Hydra clients: 0. And there is no hope to attract any.

(But Juspay uses own frameworks of the same design though)

7/

Free monads in Scala: in active usage.

Free monads in Haskell: mythologized, diminished, considered harmful.

8/

Scala: strives for success.

Haskell: avoids success at all costs.

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