Peon is a simple, functional, async-first programming language with a focus on correctness and speed
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The peon programming language

Peon is a simple, functional, async-first programming language with a focus on correctness and speed.

Go to the Manual

Project structure

  • src/ -> Contains the entirety of peon's toolchain
    • src/memory/ -> Contains peon's memory allocator and GC (TODO)
    • src/frontend/ -> Contains the tokenizer, parser and compiler
      • src/frontend/meta/ -> Contains shared error definitions, AST node and token declarations as well as the bytecode used by the compiler
    • src/backend/ -> Contains the peon VM and type system
    • src/util/ -> Contains utilities such as the bytecode debugger and serializer as well as procedures to handle multi-byte sequences
    • src/config.nim -> Contains compile-time configuration variables
    • src/main.nim -> Ties up the whole toolchain together by tokenizing, parsing, compiling, debugging, (de-)serializing and executing peon code
  • docs/ -> Contains documentation for various components of peon (bytecode, syntax, etc.)
  • tests/ -> Contains tests (both in peon and Nim) for the toolchain


  • Araq, for creating the amazing language that is Nim
  • The Nim community and contributors, for making Nim what it is today
  • Bob Nystrom, for his amazing book that inspired me and taught me how to actually make a programming language
  • Njsmith, for his awesome articles on structured concurrency

Project State

Disclaimer: The project is still in its very early days: lots of stuff is not implemented, a work in progress or otherwise outright broken. Feel free to report bugs!

Also, yes: peon is yet another programming language inspired by Bob's book, but it is also very different from Lox, which is an object-oriented, dynamically typed and very high level programming language, whereas peon is a statically-typed, functional language which aims to allow low-level interfacing with C and Nim code while being a breeze to use.

Also, peon will feature structured concurrency with coroutines (think Futures/Fibers but without callback hell). Since, unlike Lox, peon isn't a toy language, there's obviously plans to implement creature comforts like an import system, exception handling, a package manager, etc.


In no particular order, here's a list of stuff that's done/to do (might be incomplete/out of date):


  • Tokenizer (with dynamic symbol table)
  • Parser (with support for custom operators, even builtins)
  • Compiler -> Being written
  • VM -> Being written
  • Bytecode (de-)serializer
  • Static code debugger
  • Runtime debugger/inspection tool

Type system:

  • Custom types
  • Intrinsics
  • Generics -> WIP
  • Functions


  • Pragmas -> WIP (Some pragmas implemented)
  • Attribute resolution
  • method-like call syntax without actual methods (dispatched at compile-time)
  • ... More?

The name

The name for peon comes from my and Productive2's genius and is a result of shortening the name of the fastest animal on earth: the Peregrine Falcon. I guess I wanted this to mean peon will be blazing fast