The Mica compiler is a single statically linked executable plus its standard library. It has no runtime of its own to install and no daemon to run.

What you need

Two system packages, and nothing else:

PackageWhy
binutilsMica emits assembly and hands it to as and ld. It has no built-in assembler or linker.
libc6-devCompiled programs link against the C library and its startup objects.

On Debian or Ubuntu the package pulls both in automatically:

sudo apt install ./mica_<version>_<arch>.deb

The compiler binary itself is statically linked, so it has no library dependencies of its own — the two packages above are for the programs it produces, not for running the compiler.

Supported systems. 64-bit Linux with glibc, on x86_64 (x86-64-v3 or later — Intel Haswell, AMD Zen) or AArch64 (ARMv8.0-A). There is no Windows or macOS build; see platform and toolchain.

Download

amd64
Download 6.7.0
File
mica_6.7.0_amd64.deb
Size
3.2 MB
Built
2026-07-22
SHA-25689d104fb2f53388f40f8f80036abcb2fc9d58ad099948cab5cc0b330c0244f33

Version 6.7.0, built from commit de623e10. Verify a download with sha256sum against the hash above.

Install

# from the directory holding the .deb
sudo apt install ./mica_<version>_<arch>.deb

apt resolves binutils and libc6-dev for you. If you use dpkg directly, install the dependencies afterwards:

sudo dpkg -i mica_<version>_<arch>.deb
sudo apt-get install -f

Check it worked

mica --version

Then compile something. Save this as Hello.mica:

program Hello;

imp
    WriteLn : std;

begin
    WriteLn("hello from mica");
end.

and build it:

mica --compile --link --optimize release \
     --platform linux,amd64,utf-8 \
     --source Hello.mica --build build
./build/Hello

You should see hello from mica. Substitute arm64 for amd64 on an AArch64 machine.

What gets installed

Path
/usr/bin/micathe compiler driver
/usr/lib/mica-stdlib-<arch>.athe standard library
/usr/lib/mica-stdlib-fixedarena-<arch>.afreestanding deployment class
/usr/lib/mica-stdlib-mc-<arch>.amulticore tasking
/usr/lib/mica-stdlib-fixedarena-mc-<arch>.aboth
/usr/lib/mica-stdlib-utf-8.external, …-utf-32.externalpublished import surfaces
/usr/lib/contracts/curated C, POSIX and Linux interop contracts

You do not normally name any of these. The compiler resolves the right archive from the --platform, --memory-class and --tasking you ask for, and reads the contracts when a program imports a system function.

One thing that catches people out

The string encoding is fixed per binary, and the format specifier follows it. Under utf-8 a string is %s; under utf-32 it is %ls. Get it wrong and the compiler tells you exactly which specifier it expected — it checks format strings at compile time rather than letting a mismatch reach the output.

Building for the other architecture

Cross-compiling — producing an AArch64 binary on an x86_64 machine, or the reverse — needs the cross binutils, plus a user-mode emulator if you want to run the result:

sudo apt install binutils-aarch64-linux-gnu qemu-user-binfmt
export QEMU_LD_PREFIX=/usr/aarch64-linux-gnu

Then name the target architecture in --platform:

mica --compile --link --optimize release \
     --platform linux,arm64,utf-8 \
     --source Hello.mica --build build

You also need the standard library for that architecture, which means installing the package built for it.

See also