Gossamer standard library

One page per module. Source is crates/gossamer-std/src/; this index is regenerated from manifest::ALL_MODULES by gos doc --emit-stdlib.

For receiver methods on built-in types, see Methods by type.

Module	Summary
std::archive::tar	Unix tar reader and writer (USTAR / PAX-aware decode).
std::archive::zip	ZIP archive reader and writer.
std::bufio	Buffered readers, writers, and line scanners.
std::bytes	Byte buffers, builders, and slice helpers.
std::collections	Built-in container types.
std::compress::bzip2	bzip2 encoder / decoder (BZh format).
std::compress::flate	Raw DEFLATE (RFC 1951) encoder / decoder.
std::compress::gzip	gzip encoder / decoder (RFC 1952; flate2-backed).
std::compress::zlib	zlib (RFC 1950) encoder / decoder.
std::compress::zstd	Zstandard encoder / decoder (RFC 8478; libzstd-vendored).
std::context	Request-scoped cancellation, deadlines, and timeouts.
std::crypto::aead	Authenticated encryption with associated data.
std::crypto::blake3	BLAKE3 hashing.
std::crypto::ecdsa	ECDSA over the NIST P-256 curve.
std::crypto::ed25519	Ed25519 digital signatures.
std::crypto::hmac	HMAC-SHA-256 keyed MACs.
std::crypto::insecure	Legacy / broken hashes (MD5, SHA-1). Compat only - never use for new code.
std::crypto::kdf	Password-based key-derivation functions.
std::crypto::password	Argon2id password hashing facade: PHC-string hash / verify / re-hash policy.
std::crypto::rand	Secure random bytes from the host CSPRNG.
std::crypto::sha256	SHA-256 hashing.
std::crypto::sha512	SHA-512 hashing.
std::crypto::subtle	Constant-time comparison helpers.
std::crypto::x509	X.509 certificate parsing.
std::database::sql	Driver-pluggable SQL database access. No driver ships in the box; bring your own (Postgres, MySQL, SQLite, ...) by registering one at startup.
std::encoding::ascii85	ASCII85 / base85 encode / decode.
std::encoding::base32	RFC 4648 base32 (uppercase) encode / decode.
std::encoding::base64	RFC 4648 base64 encode/decode.
std::encoding::binary	Big/little-endian integer packing and varint codecs.
std::encoding::csv	CSV record reader and writer.
std::encoding::hex	Lowercase hex encode/decode.
std::encoding::json	JSON parser, emitter, and derive support.
std::encoding::pem	PEM block encoder and decoder.
std::encoding::toml	TOML 1.0 parsing + emission. Pair with the turbofish from_toml::<Type> for typed decoding (struct auto-derive).
std::encoding::xml	Streaming XML decoder + builder (quick-xml).
std::encoding::yaml	YAML 1.2 parser/emitter (serde_norway-backed).
std::env	Process environment, command-line arguments, working directory.
std::errors	Error construction, wrapping, and chain traversal.
std::flag	Batteries-included CLI argument parsing.
std::fmt	Formatted printing and string interpolation.
std::fs	Filesystem reading, writing, and traversal (Rust std::fs shape).
std::hash::adler32	Adler-32 checksums.
std::hash::crc32	CRC-32 (IEEE) checksums.
std::hash::fnv	FNV-1a non-cryptographic hash (32-bit, 64-bit).
std::html	HTML text escaping and unescaping.
std::html::template	Context-aware HTML templates with auto-escape (text/attr/URL/JS). The context classifier is heuristic - sound for typical server-rendered responses but NOT a content-security-policy substitute; sanitize untrusted HTML fragments with a dedicated sanitizer.
std::http	HTTP/1.1 and HTTP/2 client and server. HTTP/2 negotiates via ALPN over TLS automatically (Go-style); h2c entry points are explicit. Write a handler as a cohort and an arena: cohort { } joins or cancels every goroutine the request spawned before the response is written, and its first child failure becomes the block's Err for the handler to turn into a status; arena { } bump-allocates what the request builds and frees it wholesale on every exit path, with escape checked at compile time. Dependency injection is closure capture - build the router from closures capturing the pool and the configuration.
std::http::chunked	RFC 7230 §4.1 chunked transfer-encoding reader and writer.
std::http::cookie	RFC 6265 cookie parser and Set-Cookie builder.
std::http::csrf	Double-submit-cookie CSRF protection with Origin / Referer allowlist.
std::http::form	application/x-www-form-urlencoded parser and builder.
std::http::health	Liveness and readiness endpoints are ordinary handlers over std::lifecycle: answer 200 from a liveness route, and 200/503 from lifecycle::is_ready() on a readiness route, which drops to false on its own when shutdown begins. A probe registry with per-check timeouts belongs in an application package.
std::http::middleware	Composable middleware: request_id, cors, security_headers, hsts, cache_control, etag, rate_limit, body_limit, timeout, compress_gzip, logger, recoverer, basic_auth, bearer_auth, safe_defaults.
std::http::multipart	RFC 7578 multipart/form-data streaming parser.
std::http::native_client	Goroutine-driven HTTP/1.1 client over std::net (no ureq, no blocking pool).
std::http::proxy	Reverse proxy on top of http::Client. Director-style request mutator + hop-by-hop strip + error handler.
std::http::query	A request's query string is already parsed: read request.query for the raw text and request.query_pairs for the decoded name/value pairs.
std::http::router	Go 1.22-class ServeMux: method-aware path patterns with parameter captures + prefix routes.
std::http::session	Signs and verifies a session payload. The cookie itself - name, attributes, expiry, a server-side store, id rotation on privilege change, revocation - is application policy and belongs in a session package built on these two.
std::http::sse	Server-Sent Events (text/event-stream) emitter with heartbeat ticks and retry hint.
std::http::state	Dependency injection is closure capture: build the router from closures that capture the pool, the cache, and the configuration, and each handler reads what it captured. A captured heap value is shared, so one map serves every request.
std::http::static_files	Caching static-file handler: ETag, Last-Modified, byte ranges, MIME sniff.
std::http::websocket	RFC 6455 WebSocket support. Server-side accept + send_text / send_binary / ping / pong / close.
std::http_h3	HTTP/3 over QUIC. std::http_h3 is the retained 0.27 spelling; no std::http::h3 alias.
std::httptest	Fixtures for testing HTTP code. A handler is a function from a request to a response, so record calls one in memory; a test that is about the wire builds an http::Server, binds port 0, and reads the address back.
std::image	Opaque RGBA8 image handles with PNG and JPEG codecs.
std::io	Stream-oriented I/O abstractions and process standard streams.
std::iter	Sequence adapters: map, filter, fold, zip, enumerate, chain, etc. A Vec argument is traversed eagerly; an Iterator argument keeps the adapter lazy and answers with another iterator.
std::jwt	RFC 7519 tokens. Signs with HS256 / HS384 / HS512, ES256, and EdDSA; verifies those plus the RS256 / RS384 / RS512 family every mainstream identity provider mints with. Claims cross the boundary as JSON text.
std::lifecycle	Process readiness and graceful shutdown, with systemd sd_notify. Shutdown is observed, not dispatched: wait for it, then drain with ordinary statements - spawn(|| serve()), lifecycle::ready(), lifecycle::await_shutdown(), then the cleanup.
std::math	Mathematical constants and f64 functions (Go's math package shape).
std::math::big	Arbitrary-precision integers (num-bigint).
std::math::bits	Integer bit-manipulation operations (Go's math/bits shape).
std::math::rand	Deterministic pseudo-random number generation.
std::metrics	Prometheus-compatible primitives (Counter, Gauge, Histogram) and a Registry rendering the standard text-exposition format.
std::mime	RFC 2045 media type parsing, parameter extraction, and extension lookup.
std::net	TCP/UDP networking primitives.
std::net::ip	String-level IPv4 / IPv6 parsing and classification helpers.
std::net::netip	Typed IP-address parsing, classification, and addr:port helpers (Go's net/netip shape).
std::net::smtp	Sends one message per call, so an application can mail a password reset, an address verification, a magic link, or a security notice. A pool, a queue, retries, and bounce handling are application policy and belong in a package built on these. Port 465 speaks TLS from the first byte; any other port starts in the clear and upgrades through STARTTLS when the server offers it, and credentials are refused rather than sent to a server offering no encryption.
std::net::url	Network URL parsing and component escaping; never use filesystem-path rules.
std::option	Data-last Option combinators for pipeline chaining: map, filter, unwrap_or, and_then, etc.
std::os	Operating-system identity.
std::os::exec	Deprecated compatibility facade for child processes; new code uses std::process.
std::os::signal	POSIX-style signal subscription (Go's os/signal shape).
std::os::user	POSIX user / group lookup. Unix-backed by nix; Windows falls back to env vars.
std::panic	Panic / catch_unwind integration.
std::path	Lexical filesystem-path operations; platform path grammar, no URL parsing.
std::pprof	Runtime profiles in the text format go tool pprof reads, plus a Chrome-trace scheduler capture.
std::process	Canonical process control and child-process API; std::os::exec is compatibility-only.
std::regex	Compiled regular expressions (Rust regex crate syntax; no backreferences or look-around).
std::result	Data-last Result combinators for pipeline chaining: map, map_err, unwrap_or_else, etc.
std::runtime	Goroutine / scheduler introspection and tuning.
std::slog	Structured, levelled logging.
std::sort	Explicit stable ordering and sorted-sequence search, the deliberate counterpart to Vec's unstable inherent sort.
std::strconv	Conversions between strings and primitive numeric types.
std::strings	String operations.
std::sync	Synchronisation primitives beyond channels.
std::testing	Assertions and sub-test harness helpers.
std::thread	OS-thread scheduling hints and CPU introspection; user concurrency uses goroutines, not thread spawning.
std::time	Wall-clock and monotonic time facilities.
std::tls	Rustls-backed TLS support exposed through http::serve_tls and net::TcpStream TLS upgrades. The configuration constructors are host-runtime internals, not Gossamer callables.
std::trace	W3C trace-context-compatible distributed tracing. Identifier types, request-scoped SpanContext, process-level Tracer, and OTLP JSON export.
std::unicode	Unicode general-category predicates, casing, normalization, and segmentation.
std::utf16	UTF-16 encoding/decoding and surrogate pair helpers.
std::utf8	UTF-8 validation and scalar decoding.
std::uuid	UUID v4 (random) and v7 (timestamp-ordered) generation, parse, and normalize.
std::validate	Trait-based field validation: implement Validate, collect FieldErrors into Errors.