Environment variables

Recognised by the make run / make linux / etc. entry points.

Var	Values	Default	Effect
`DEBUG`	`y` / `n`	`n`	`y` routes UART to a PTY, enables richer logging, and turns off release optimisations. Always set `DEBUG=n` when benchmarking.
`LOG`	`trace` / `debug` / `info` / `warn` / `error` / `off`	`info`	xlogger verbosity. `trace` is per-instruction.
`X_HARTS`	integer ≥ 1	`1`	Guest hart count (cooperative scheduler).
`X_FILE`	path	set by per-target Makefile	ELF to execute. Don't set manually — let `make run` resolve it.
`DIFFTEST`	`0` / `1`	`0`	Compile-in QEMU / Spike difftest backends.
`AM_HOME`	path	`${workspace}/xam`	Where xam HAL sources live.
`XEMU_HOME`	path	`${workspace}/xemu`	Where xemu workspace lives.
`XLIB_HOME`	path	`${workspace}/xlib`	Where xlib (klib) sources live.

CI-only

Var	Effect
`ECC_DISABLED_HOOKS`	Disable specific Everything-Claude-Code plugin hooks by hook ID.
`ECC_HOOK_PROFILE`	`minimal` / `standard` / `strict` — coarse toggle.

Runtime (xdb REPL)

Not env vars — commands inside the monitor. See The xdb debugger.