# basics hello-world values variables mutation literals constants for if-else case arrays sum range floats slices maps nesting functions returns varadic closures recursion defer panic recover pointers new structs fields methods embedding interfaces ok-guards errors # concurrency goroutines concurrency channels buffering directions synchronization select timeouts scatter-gather rate-limiting burstable-rate-limiting worker-pool # core libraries sort sort-by-function string-functions string-formatting regexs bytes json sha1-hashes time epoch elapsed timers tickers rand number-parsing enumerable urls # systems file-open file-read file-write command-line-arguments command-line-flags env signals exit spawn exec reading-input users line-filter # network clients tcp-client http-client http-client-basic https-client redis postgres email # network servers tcp-server # web apps http-server-basic http-server-canonical-host http-server-graceful-shutdown http-server-log http-server-middleware http-server-routing http-server-static-dynamic http-server-static-select http-server-static http-server-status-code http-server https-server