MicroHs, a tiny Haskell Compiler

on YouTube ↗01h 06m

" summary

MicroHs is a tiny Haskell compiler that translates Haskell to Turner-style combinators, emits a C byte array, then uses a C compiler to produce a compact runtime-linked executable. It produces a ~300 KB binary (vs ~37 MB when built with GHC), recompiles itself in ~8–11s, and measures ~3 ns per combinator reduction. It supports cross-compilation and runs on microcontrollers (Morse demo), serializes cached graphs for fast incremental builds.

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" chapters (28)

1. 0:00· Introducing Lennart Augustsson
2. 1:50· What is microHs? A small Haskell compiler
3. 3:22· Live installation demo
4. 5:14· Interactive mode and math with complex numbers
5. 6:37· Compiling and running Haskell programs
6. 8:10· Comparing binary sizes: microHs vs. GHC
7. 10:13· Cross-compilation & WebAssembly support
8. 14:02· Why build another Haskell compiler?
9. 16:12· Combinator-based compilation (Turner-style)
10. 17:02· Running on bare metal and microcontrollers
11. 19:54· microHs vs. GHC: Speed and binary size
12. 21:16· Implemented language extensions
13. 23:22· Limitations: No Template Haskell, some concurrency
14. 24:00· microCabal: Building packages without full Cabal
15. 26:00· Compiler architecture overview
16. 27:48· Serialization and caching
17. 30:00· Church & Scott encoding of data types
18. 33:15· Overview of SKI combinators
19. 36:02· Optimization rules and combinator reduction
20. 38:10· Self-optimizing properties of combinators
21. 40:14· Specialization and dictionary elimination
22. 44:23· The C runtime and performance: ~3ns per reduction
23. 46:22· Garbage collection: bitmap-based strategy
24. 49:28· Compilation statistics: combinators, GC, runtime
25. 51:19· Serialization formats and portability
26. 53:28· Running microHs on microcontrollers (Morse demo)
27. 54:10· Community contributions & thanks
28. 55:26· Audience Q&A: Hardware execution, performance, IO, etc.

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