xtc

xtc is an ObjC-like language that compiles to 6502 assembly for the Atari 8-bit family amongst other targets. On machines that need it, it treats bank-switched RAM as a first-class resource — programs spread code and data across paged windows and grow well beyond normal RAM limits, with the compiler deciding what lives where — and the language provides Classes (single inheritance from a root class, with Protocols for cross-class behaviour), and automatic reference counting on top of fixed-width types to optimise the best performance out of machines from 8 to 64 bits.

For the Atari 8-bit ranges, the toolchain presents as a cross-compiler with three pieces: xtc, the compiler (.xt source → 6502 assembly, or straight to a runnable Atari .xex); xta, a two-pass assembler that emits XEX with RUNAD/INITAD and banked preload; and xts, a headless simulator that runs .xex files with the same memory-model semantics the codegen targets.

These pages cover the language and its toolchain:

• Language reference — syntax, types, memory models, classes, inheritance, ARC, and inline assembly. Start here for what xtc is.
• Standard library — the classes shipped under support/lib/, with method signatures and example usage — what’s already built for you.
• Compiler usage — CLI flags, optimisation levels, allocator and memory-model selection, banking, and linker scripts — how to get the best output.
• Future work — the in-progress back-end rebuild around an architecture-neutral IR with pluggable backends: a native arm64 backend and a redesigned FPGA 6502 core with a hidden hardware stack.

Prebuilt binaries for macOS, Linux, and Windows are on the Downloads page.