🏞️ An ergonomically typed programming language.
Clone or download
Failed to load latest commit information.
apps some cleanup - rewrite tee Jun 22, 2018
bench fix linux build and tests - implement pkg-config link-ins Oct 2, 2018
docs add name assignment to midway pattern match terms - proliferate botto… Nov 15, 2018
lib clean up AST rendering a bit Nov 15, 2018
play add name assignment to midway pattern match terms - proliferate botto… Nov 15, 2018
src clean up AST rendering a bit Nov 15, 2018
tests add name assignment to midway pattern match terms - proliferate botto… Nov 15, 2018
.dockerignore rename nil to null - tons of other fixes to get tests passing again o… Dec 23, 2017
.gitignore move sources into src dir Dec 31, 2017
.lldb-script initial commit Jun 4, 2016
.travis.yml some cleanup Mar 9, 2017
CMakeLists.txt replace gc with Boehm conservative GC Sep 25, 2018
Dockerfile fix linux build and tests - implement pkg-config link-ins Oct 2, 2018
LICENSE get most basic memory management scenarios working - added tons of de… Mar 1, 2017
Makefile allow for brew installed llvm on macos Sep 14, 2018
README.md update readme Jun 21, 2018
TODO.md update readme Jun 21, 2018
VERSION some cleanup Mar 9, 2017
docker-build.sh introduce "link in" syntax for requiring linker flags Dec 10, 2017
docker-run.sh try fixing docker Jun 18, 2018
docker-test.sh test fixes Jun 19, 2018
expect-tests.sh optimize expect-tests Jun 21, 2018
expect.zion fix expect tests - allow for finding modules in the local dir Jun 24, 2018
llvm-build.sh fix rpath to ensure dylib loads at runtime Jul 17, 2018
llvm.list wip Aug 26, 2017
type_parser.cpp wip Jun 14, 2018
types.md rename def to fn May 17, 2018
ubuntu-setup.sh try to fix travis ci builds Sep 11, 2017
zion.jpg add link_names - alter the link statement syntax to allow for 'link l… Feb 3, 2017


Zion Language

Build Status

About Zion

  • imperative
    • strict (deterministic ordering of operations)
    • impure by default (with purity available)
    • caters to sequential statements and special control flow forms (like for, if, while as much as it does to expressions)
  • functional
    • first-class anonymous functions
    • capture by value (NB: types can define their internal mutability)
  • strongly-typed
    • unsafe casts are possible, but conspicuous
  • statically type-checked
    • support for compile-time type-expression evaluation
    • types are/can be inferred
    • polymorphism
      • parametric
      • ad-hoc (though currently w/o type classes)
  • algebraic data types
    • product types
    • sum types
    • pattern matching with robust coverage analysis
  • some-cost abstractions
    • garbage collection
    • deterministic destruction via
      • with special-form
      • defer for block-level determinism

Zion prefers correctness and refactorability over performance. Zion targets scenarios where scalability is intended to happen horizontally, not vertically. That being said, Zion tries to be fast, using static compilation. Zion is built on LLVM.

User Roles

  • In industry there are two primary archetypes of programming language users, Workers and Librarians. Experienced developers wear either of these hats, switching back and forth as necessary. This switching can happen as new dependencies and integrations are initiated and completed within the scope of feature or product work.
    • Workers build trustworthy applications that solve problems. Workers demand a pleasant and ergonomic experience in order to remain focused on reaching their objectives.
    • Librarians extend the capabilities of the language by
      • Creating bindings to external libraries,
      • Integrating functionality
      • Exposing extrinsic data via serialization that maintains type-safety and ergonomics to the Workers.


  • Keep it simple, when possible.
  • Keep it readable, when possible.
  • Make algebraic data types compelling for state modeling.
  • Reduce pain near process boundaries. Be opinionated on how to make serialization as comfortable as possible while retaining static type safety.


  • Solving heavy compute/FPU problems is a non-goal in the near future. Solve those problems at a lower level, and use the FFI to access those components. Favor algorithmic scaling over bit twiddling and fretting over L1 cache hits.
  • Pause-free execution remains a back-burner goal. (ie: Enabling Game loops, high-speed trading platforms, life support monitoring, embedded systems, etc...) However, in a future version, once language development settles down a bit, this will get more attention.
  • In-language concurrency and asynchronicity will get treatment in the future. These can currently be solved at other levels of the stack (hint: use OS processes.) This is not because it's not important. But, basic ergonomics of the language come first.

Syntax Examples

Zion syntax is in the C family.

module hello_world

fn main() {
	print("Hello, world!")

Comments use #.

fn favorite_number(x int) bool {
	# This is a comment
	return x == 12

Zion is strict by default, not lazy. Memory is managed using garbage collection.

Types are declared as follows:

# Declare a structure type (aka product type, aka "struct")
type Vector2D has {
	x float
	y float

type Mammal is {
    Giraffe(name str, age int, number_of_spots int)
    Lion(name str, age int)
    Mouse(fur_color str)
    Bison(favorite_national_park NationalPark)

type NationalPark is {

Development Environment Setup

You'll need LLVM. Zion is using the release_40 checkpoint of LLVM currently. The llvm-build.sh script will clone the LLVM (and clang, etc...) sources from github onto your machine, and try to build them. It will attempt to install into the $HOME/opt/llvm/release_40/{MinSizeRel,Debug} directories. Theoretically you only need the MinSizeRel build to work with, however it can be useful to drop into the Debug build from time to time. That will require repointing your config as appropriate.

Add the following to your .bashrc (or equivalent), assuming you have cloned Zion into $HOME/src/zion:

export PATH="$LLVM_DIR/bin:$PATH"
export ZION_PATH=$ZION_SRC:$ZION_SRC/lib:$ZION_SRC/tests:$HOME/var/zion