Exec plugins

The single biggest reason a Nagios migration stalls is “we have 400 plugins and nobody wants to rewrite them.” jaque’s answer: don’t. Any executable that speaks the Nagios exec convention — exit 0/1/2/3 for OK/WARNING/CRITICAL/UNKNOWN, with output (optionally carrying |-delimited perfdata) on stdout — runs on jaque unmodified, and this is permanent supported surface, not a deprecation runway: vendor monitoring plugins, in-house scripts written a decade ago, anything a check_command in an imported config resolves to, all of it keeps working without a rewrite deadline.

See Legacy exec plugins for the protocol detail, the perfdata format, and process-group timeout handling. WASM checks exist alongside this for new work you’d rather sandbox and ship as one file, not to replace it.