Key Standard Library Packages

net                  - TCP/UDP/Unix sockets, Dialer, Listener, IPNet
net/http             - HTTP server/client, middleware, handlers, httptest
net/http/httputil    - ReverseProxy, DumpRequest
crypto/tls           - TLS 1.2/1.3, ClientHelloInfo, Config, mTLS
crypto/x509          - Certificate parsing, generation, CA operations
crypto/ecdsa         - ECDSA signing/verification (tokens, mTLS)
crypto/rsa           - RSA key generation
crypto/elliptic      - P-256, P-384 curves
crypto/aes           - AES-256 encryption
crypto/cipher        - GCM, CBC modes
crypto/hmac          - HMAC-SHA256 (request signing, PoW, webhook)
crypto/sha256        - Hashing, PoW challenges, JA3
crypto/md5           - JA3 fingerprint hash (not for security use)
crypto/rand          - Cryptographically secure random (nonces, tokens)
crypto/subtle        - Constant-time comparison (auth paths)
sync                 - Mutex, RWMutex, WaitGroup, Once, Pool, Map
sync/atomic          - Lock-free counters (connection counts, flags)
context              - Cancellation, timeouts, value propagation
encoding/binary      - Packet/protocol parsing (big/little endian)
encoding/json        - JSON encode/decode, streaming, schema validation
encoding/hex         - Hex encoding for fingerprints, tokens
regexp               - WAF pattern matching (pre-compiled)
log/slog             - Structured logging, JSON handler (Go 1.21+)
net/http/pprof       - CPU/heap/goroutine profiling endpoints
expvar               - Runtime metrics exposure (/debug/vars)
testing              - Unit tests, table-driven tests
testing/fuzz         - Fuzz testing for parsers and validators
os/signal            - Signal handling (SIGTERM, SIGHUP, SIGUSR*)
runtime              - GC tuning, goroutine count, stack dumps
html                 - HTML entity unescaping (WAF normalization)
bufio                - Buffered I/O for protocol parsing
io                   - Reader/Writer composition, TeeReader, Pipe
time                 - Timeouts, rate limiting windows, TTL, metrics
container/heap       - Priority queue (task scheduler)