| flag | Package flag implements command-line flag parsing. |
| github.com/prometheus/client_golang/prometheus | Package prometheus is the core instrumentation package. |
| math | Package math provides basic constants and mathematical functions. |
| math/rand | Package rand implements pseudo-random number generators suitable for tasks such as simulation, but it should not be used for security-sensitive work. |
| net/http | Package http provides HTTP client and server implementations. |
| time | Package time provides functionality for measuring and displaying time. |