# Callisto

**Source:** https://github.com/callisto-lang/compiler

GitHub - callisto-lang/compiler: The Callisto compiler of the 13th month, and other language extras



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**[compiler](/callisto-lang/compiler)**
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The Callisto compiler of the 13th month, and other language extras

[callisto.mesyeti.uk](https://callisto.mesyeti.uk "https://callisto.mesyeti.uk")

### License

[MIT license](/callisto-lang/compiler/blob/main/LICENSE)

[76
stars](/callisto-lang/compiler/stargazers) [8
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# callisto-lang/compiler

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## Folders and files

| Name | | Name | Last commit message | Last commit date |
| --- | --- | --- | --- | --- |
| Latest commit   History[474 Commits](/callisto-lang/compiler/commits/main/)   474 Commits | | |
| [.gitub-temp-disabled/workflows](/callisto-lang/compiler/tree/main/.gitub-temp-disabled/workflows "This path skips through empty directories") | | [.gitub-temp-disabled/workflows](/callisto-lang/compiler/tree/main/.gitub-temp-disabled/workflows "This path skips through empty directories") |  |  |
| [docs](/callisto-lang/compiler/tree/main/docs "docs") | | [docs](/callisto-lang/compiler/tree/main/docs "docs") |  |  |
| [editors](/callisto-lang/compiler/tree/main/editors "editors") | | [editors](/callisto-lang/compiler/tree/main/editors "editors") |  |  |
| [examples](/callisto-lang/compiler/tree/main/examples "examples") | | [examples](/callisto-lang/compiler/tree/main/examples "examples") |  |  |
| [source](/callisto-lang/compiler/tree/main/source "source") | | [source](/callisto-lang/compiler/tree/main/source "source") |  |  |
| [std @ 4c0918c](/callisto-lang/std/tree/4c0918cfa12a9b80f65732b044a0a0c11365204e "std") | | [std @ 4c0918c](/callisto-lang/std/tree/4c0918cfa12a9b80f65732b044a0a0c11365204e "std") |  |  |
| [.gitattributes](/callisto-lang/compiler/blob/main/.gitattributes ".gitattributes") | | [.gitattributes](/callisto-lang/compiler/blob/main/.gitattributes ".gitattributes") |  |  |
| [.gitignore](/callisto-lang/compiler/blob/main/.gitignore ".gitignore") | | [.gitignore](/callisto-lang/compiler/blob/main/.gitignore ".gitignore") |  |  |
| [.gitmodules](/callisto-lang/compiler/blob/main/.gitmodules ".gitmodules") | | [.gitmodules](/callisto-lang/compiler/blob/main/.gitmodules ".gitmodules") |  |  |
| [LICENSE](/callisto-lang/compiler/blob/main/LICENSE "LICENSE") | | [LICENSE](/callisto-lang/compiler/blob/main/LICENSE "LICENSE") |  |  |
| [README.md](/callisto-lang/compiler/blob/main/README.md "README.md") | | [README.md](/callisto-lang/compiler/blob/main/README.md "README.md") |  |  |
| [STYLE.md](/callisto-lang/compiler/blob/main/STYLE.md "STYLE.md") | | [STYLE.md](/callisto-lang/compiler/blob/main/STYLE.md "STYLE.md") |  |  |
| [TODO.md](/callisto-lang/compiler/blob/main/TODO.md "TODO.md") | | [TODO.md](/callisto-lang/compiler/blob/main/TODO.md "TODO.md") |  |  |
| [dub.json](/callisto-lang/compiler/blob/main/dub.json "dub.json") | | [dub.json](/callisto-lang/compiler/blob/main/dub.json "dub.json") |  |  |
| [flake.nix](/callisto-lang/compiler/blob/main/flake.nix "flake.nix") | | [flake.nix](/callisto-lang/compiler/blob/main/flake.nix "flake.nix") |  |  |
| View all files | | |

## Repository files navigation

* [README](#)
* [MIT license](#)

[![](https://camo.githubusercontent.com/4bdb739c0513e67abf8868948c01b60d12189f18d85f06ebb6abd6cf6e156804/68747470733a2f2f63616c6c6973746f2e6d6573796574692e756b2f6c6f676f5f736861646f772e706e67)](https://camo.githubusercontent.com/4bdb739c0513e67abf8868948c01b60d12189f18d85f06ebb6abd6cf6e156804/68747470733a2f2f63616c6c6973746f2e6d6573796574692e756b2f6c6f676f5f736861646f772e706e67)

# The Callisto Programming Language

[Website](https://callisto.mesyeti.uk/) |
[Docs](https://callisto.mesyeti.uk/docs) |
[Awesome List](https://github.com/callisto-lang/awesome-callisto) |
[Discord](https://discord.com/invite/QHAtc4GWq7)

**Callisto** is a stack-based imperative programming language with stack safety enforced
by the compiler (which is optional).

It also has a subset called CallistoScript made to compile to scripting languages like
Lua, while keeping its low level features (like direct access to memory).

## Supported targets

* x86 real mode - MS-DOS, bare metal
* x86\_64 - Linux, macOS, FreeBSD (partial)
* ARM64 - Linux, macOS
* Uxn - Varvara
* Lua

## Build

```
dub build --compiler=ldc
```

The compiler executable will be called `cac`

Warning

Compilation may freeze due to a bug in the Digital Mars D compiler. If this happens,
compile with this command: `dub build --compiler=ldc`.

If that doesn't work, then run with `--compiler=ldc2` instead.

## Run example programs

Make sure you get the standard library

```
git submodule update --remote
```

Then compile example programs like this

```
cac examples/exampleNameHere.cal -i std
```

The output executable will be called `out`. Any example programs that require extra flags
for compilation will have a compile command in a comment at the top of the source file.

## IRC Channel

Join `#callisto-lang` on irc.libera.chat.

## About

The Callisto compiler of the 13th month, and other language extras

[callisto.mesyeti.uk](https://callisto.mesyeti.uk "https://callisto.mesyeti.uk")

### Topics

[programming-language](/topics/programming-language "Topic: programming-language")
[compiler](/topics/compiler "Topic: compiler")
[x86-64](/topics/x86-64 "Topic: x86-64")
[concatenative](/topics/concatenative "Topic: concatenative")
[concatenative-language](/topics/concatenative-language "Topic: concatenative-language")
[concatenative-programming-language](/topics/concatenative-programming-language "Topic: concatenative-programming-language")
[uxn](/topics/uxn "Topic: uxn")
[uxntal](/topics/uxntal "Topic: uxntal")

### Resources

[Readme](#readme-ov-file)

### License

[MIT license](#MIT-1-ov-file)

### Uh oh!

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[Activity](/callisto-lang/compiler/activity)

[Custom properties](/callisto-lang/compiler/custom-properties)

### Stars

[**76**
stars](/callisto-lang/compiler/stargazers)

### Watchers

[**1**
watching](/callisto-lang/compiler/watchers)

### Forks

[**8**
forks](/callisto-lang/compiler/forks)

[Report repository](/contact/report-content?content_url=https%3A%2F%2Fgithub.com%2Fcallisto-lang%2Fcompiler&report=callisto-lang+%28user%29)

## [Releases 23](/callisto-lang/compiler/releases)

[Beta 0.13.0 - Modules part 1

Latest

Nov 15, 2025](/callisto-lang/compiler/releases/tag/b0.13.0)

[+ 22 releases](/callisto-lang/compiler/releases)

## [Packages 0](/orgs/callisto-lang/packages?repo_name=compiler)

No packages published

### Uh oh!

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## [Contributors 7](/callisto-lang/compiler/graphs/contributors)

### Uh oh!

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## Languages

* [D
  99.6%](/callisto-lang/compiler/search?l=d)
* [Nix
  0.4%](/callisto-lang/compiler/search?l=nix)

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