Toolchain

Commands

Check, format, inspect, run, build, test, and manage an Echo project.

Surface

run compiles and executes through one clang -O0 -g link and libecho_runtime. --jit executes the same LLVM IR in-process. Debug metadata carries per-statement source lines and checker kind labels for locals. Commands that analyze a program take its entry file and resolve the closed import graph from there.

xo check <entry.echo>
xo fmt <file.echo>
xo lex <file.echo>
xo ast <file.echo>
xo ir <entry.echo>
xo run [--jit] [-O <level>] <entry.echo> [args...]
xo build [-O <level>] <entry.echo> -o <out>
xo test <path>
xo repl
xo lsp
xo get <package[@version]> [--deps]
xo home
xo cache status|clean|gc|doctor
xo index scan [roots...]
xo tools grammar tree-sitter --output <dir>

Optimization

-O accepts 0, 1, 2, 3, or z. Both AOT run and build default to level 0.

Gates

scripts/gate changed for a tight loop. scripts/gate workspace before broad commits. scripts/gate web for this site. Language changes should keep the Echo 2026 suite (e26) green.