- Cargo workspace (core, plugins, tui, cli) with drop-in compatible CLI - Python-compatible config file handling, limits, views, rates, MMM, history - process collection via sysinfo + procfs, filters, thresholds, events, actions - 20 core plugins (cpu, percpu, mem, memswap, load, fs, network, diskio, ...) - stdout, stdout-csv, stdout-json, --issue, --modules-list output modes - differential test harness against the Python implementation