platform

Package buildinfo tells the version of the running binary.

Package cache keeps registry answers in memory for a while, so a burst of checks on the same identifier calls an upstream once (ADR 0002).

Package clock gives the commands the system time, pauses and jitter that the use cases take as ports, so the use cases stay testable.

Package config reads the configuration of every command from environment variables into one typed Config, validated as a whole at startup so a command stops before doing anything with a value it cannot use (ADR 0002).

Package csvfile reads the semicolon- or comma-separated files upstream sources publish, record by record, after checking their header.

Package defaults fills the zero fields of a configuration struct with their default value, so every Config in platform follows the same rule: zero means default, negative is invalid.

Package httpclient is the only way out to the network: every source and registry fetches through a Client (ADR 0002).

Package logging builds the structured logger every command writes with: log/slog lines in JSON, personal data masked, the request identifier of the context added (ADR 0002).

Package ratelimit limits the requests of each client with a token bucket per key, in memory and bounded: an idle bucket is forgotten, and the number of buckets is capped.

Package startup is what every command does before its own work: load the typed configuration, build the redacting logger from it and make that logger the log/slog default, so no line written by the command or a library bypasses the masking of personal data (ADR 0002).

Package throttle keeps the registry clients away from an upstream that asked to wait with a Retry-After header (RFC 9110, section 10.2.3), so a check fails fast instead of calling it again too soon.