| context | Package context defines the Context type, which carries deadlines, cancellation signals, and other request-scoped values across API boundaries and between processes. |
| crypto/rsa | Package rsa implements RSA encryption as specified in PKCS #1 and RFC 8017. |
| crypto/x509 | Package x509 implements a subset of the X.509 standard. |
| encoding/json | Package json implements encoding and decoding of JSON as defined in RFC 7159. |
| encoding/pem | Package pem implements the PEM data encoding, which originated in Privacy Enhanced Mail. |
| errors | Package errors implements functions to manipulate errors. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| golang.org/x/net/context/ctxhttp | Package ctxhttp provides helper functions for performing context-aware HTTP requests. |
| io | Package io provides basic interfaces to I/O primitives. |
| io/ioutil | Package ioutil implements some I/O utility functions. |
| math | Package math provides basic constants and mathematical functions. |
| mime | Package mime implements parts of the MIME spec. |
| net/http | Package http provides HTTP client and server implementations. |
| net/url | Package url parses URLs and implements query escaping. |
| strconv | Package strconv implements conversions to and from string representations of basic data types. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |
| sync | Package sync provides basic synchronization primitives such as mutual exclusion locks. |
| time | Package time provides functionality for measuring and displaying time. |