src/workerd/api/

All JavaScript APIs exposed to Workers: HTTP, crypto, streams, WebSocket, Cache, KV, R2, SQL, encoding, events, timers, scheduled/alarm handlers.

STRUCTURE

*.h + *.c++          # Top-level API impls (http, headers, cache, blob, url, events, etc.)
crypto/              # WebCrypto + Node crypto: AES, RSA, EC, DH, HKDF, PBKDF2, X.509, JWK
streams/             # ReadableStream/WritableStream/TransformStream (internal + standard); has README.md
node/                # Node.js compat C++ layer; register new modules in NODEJS_MODULES macro in node.h
pyodide/             # Python Workers Pyodide/Emscripten bridge (7 files)
tests/               # JS integration tests (238 entries); each test = .js + .wd-test pair

WHERE TO LOOK

Task	Files
fetch / Request / Response	http.h, http.c++
Headers	headers.h, headers.c++
WebSocket	web-socket.h, web-socket.c++
Hibernatable WS (DO)	hibernatable-web-socket.h
GlobalScope / addEventListener	global-scope.h, global-scope.c++, basics.h
JS RPC / Fetcher	worker-rpc.h, worker-rpc.c++
Durable Object state	actor-state.h, actor.h
Streams internals	streams/ (see streams/README.md for architecture)
Crypto (WebCrypto)	crypto/crypto.h, crypto/impl.h, crypto/keys.h
Node.js compat (C++)	node/node.h (NODEJS_MODULES macro), per-module .h
URL (legacy vs standard)	url.h (legacy), url-standard.h (spec-compliant)
Encoding (TextEncoder/Dec)	encoding.h; stream variants in streams/encoding.h
Scheduled / Queue / Alarm	scheduled.h, queue.h, actor-state.h
HTMLRewriter	html-rewriter.h
R2 storage	r2-bucket.h, r2-multipart.h
KV / SyncKV	kv.h, sync-kv.h
SQL (DO)	sql.h
Body mixin (shared Req/Res)	http.h — Body class, Body::Initializer OneOf

CONVENTIONS

• global-scope.h forward-declares most API classes; ServiceWorkerGlobalScope registers all nested types
• Node.js compat: add C++ class + register in NODEJS_MODULES(V) macro in node/node.h; experimental modules go in NODEJS_MODULES_EXPERIMENTAL(V)
• URL has dual impl: legacy (url.h) vs standard (url-standard.h); compat flag selects which
• Streams has dual impl: internal (streams/internal.h) vs standard (streams/standard.h)
• Test naming: tests/<feature>-test.js + tests/<feature>-test.wd-test; C++ unit tests: <feature>-test.c++