Coatl

Coatl follows an ancient, sleek serpent aesthetic: fluid paths, precise control, and minimal friction.

Coatl is a native systems language focusing on x86_64 and AArch64 Linux backends. The compiler is implemented in Rust.

Documentation

The official documentation is available on the GitHub Wiki: https://github.com/euxaristia/Coatl/wiki

Quick Start

Here is a simple "Hello, world!" program in Coatl (examples/hello.coatl):

import "std/io"

fn main() returns i32 {
  io.print("Hello, world!\n")
  return 0
}

Build and install the compiler:

cargo build --release

Build a native x86_64 Linux binary:

./target/release/coatl examples/hello.coatl -o /tmp/hello
/tmp/hello

Build x86_64 assembly:

./target/release/coatl examples/hello.coatl -o /tmp/hello.s

Emit textual IR:

./target/release/coatl examples/hello.coatl -o /tmp/hello.ir

Core Tooling

Usage:

coatl <input.coatl|input.ir> [-o output] [--arch=<arch>]

Output format is inferred from the -o extension:

• .s — assembly source
• .ir — textual IR
• anything else — linked ELF binary

Environment flags:

• CC — override the C compiler/linker (default: cc)
• --arch=x86_64|aarch64 — target architecture (default: x86_64)

Terminal Raw Mode Intrinsics

For terminal games on Linux, Coatl exposes:

• __tty_get_mode(fd: i32, out_ptr: i32) -> i32
• __tty_set_raw(fd: i32, mode_ptr: i32, vmin: i32, vtime: i32) -> i32
• __tty_restore(fd: i32, mode_ptr: i32) -> i32
• __tty_get_size(fd: i32, out_ptr: i32) -> i32

Behavior:

• Native (Linux): backed by termios (ioctl), returns 0 on success or errno on failure.
• Non-TTY stdin is preserved: calls fail with errno from the OS (for example ENOTTY).

Caveats:

• Raw mode should always be restored before process exit.

Validation

Run all tests:

cargo test

Repository Layout

• examples/ — sample programs
• tests/ — integration and smoke suites
• src/ — compiler source (Rust)
• runtime/ — intrinsics assembly (intrinsics.s, intrinsics_aarch64.s)
• std/ — standard library modules
• man/ — manual pages

Safety & Memory Model

Coatl is a low-level systems language. It is not memory safe and provides fewer guardrails than C.

• Manual Memory: Memory is accessed via raw intrinsics (__mem_load/__mem_store) with integer addresses. No pointers or bounds checks.
• System Access: Direct interaction with Linux system calls via assembly templates.