Networking & protocols
Networking core371+ →
xrtNet / Tcp / Udp / NetServer / NetStream — connections, listening (SHARED / REUSE_PORT), datagrams, address resolution
TLS 1.2 / 1.3252+ →
xrtTls / Tls12 / Tls13 — handshake, records, session resumption PSK / Ticket; plus the tls_server / tls_client / tls_stream volumes
Certificates / ASN.1123+ →
xrtX509 / Der / Pem — chain building and validation, name constraints, CRL, system trust stores
HTTP / 1.1149 →
xrtHttp / Http1 — the parser (35 error codes), ResponseWrite, Chunk, BodyRead; http1_net / http1_tls volumes
WebSocket104 →
xrtWs — frames, streams, Upgrade, permessage-deflate, refcounted reads/writes; the websocket_stream volume
Crypto / hashing100+ →
The SHA family, HMAC / HKDF / PBKDF2, AES, RSA / ECDSA / Ed25519; the hash / compress volumes
Data & text
Dynamic values116 →
xrtValue — object / array / tree construction and access, reference counting; a full practice chapter in ch. 18
JSON / XSON65 →
xrtJsonParse / Stringify; the xson streaming variant
Strings / Unicode133 →
xrtStr / Utf8 / Utf16 / Utf32 — views, conversion, casing, validation
Regex / patterns91 →
xrtRegex / RegexSet / Pattern — NFA regex, batch precompiled route patterns; a full practice chapter in ch. 17
Templates32 →
xrtTemplateCompile / Render — {$var} and {#foreach}; a full practice chapter in ch. 19
Containers≈160 →
Map / Array / List / Set / AVL / Stack / Buffer / SlotMap (each module its own volume)
System & concurrency
Concurrency≈220 →
xrtCo coroutines / Channel (Go-style) / Task / Future / Executor (work-stealing) / Thread — each module its own volume
Files / paths118 →
xrtFile (with the file_async volume) / Path / Dir — sync and async IO, directory trees, path normalization
Memory≈90 →
xrtMem / Temp (the temporary allocator) / Pool; the memory_debug / memory_stats volumes add canary / UAF / reports
Logging76 →
xrtLog — levels, formatting, multiple outputs (replacing bare printf)
Processes / system≈40 →
xrtProcess (child processes / pipes) / Signal / Environment
All 91 modules3,030 →
The xrt site's API search page (Ctrl+K, 6,276 indexed functions); the unlisted small domains (Time / Atomic / Math / Random / Html / Codec …) make up the remainder