| errors | Package errors implements functions to manipulate errors. |
| flag | Package flag implements command-line flag parsing. |
| github.com/gorilla/websocket | Package websocket implements the WebSocket protocol defined in RFC 6455. |
| io | Package io provides basic interfaces to I/O primitives. |
| log | Package log implements a simple logging package. |
| net/http | Package http provides HTTP client and server implementations. |
| time | Package time provides functionality for measuring and displaying time. |
| unicode/utf8 | Package utf8 implements functions and constants to support text encoded in UTF-8. |