| encoding/json | Package json implements encoding and decoding of JSON objects as defined in RFC 4627. |
| golang.org/x/blog/content/context/userip | Package userip provides functions for extracting a user IP address from a request and associating it with a Context. |
| golang.org/x/net/context | Package context defines the Context type, which carries deadlines, cancelation signals, and other request-scoped values across API boundaries and between processes. |
| net/http | Package http provides HTTP client and server implementations. |