The CLI

dynamic-config-cli is command-line diagnostics for configuration this crate loads: the dynamic-config binary.

cargo install dynamic-config-cli

A CLI cannot see an application's #[dynamic_config] attribute or its builder, so it builds the load from flags — explain is the command-line form of check(), pointed at one path. What the flags describe must match what the application declares, or the answer is about a different load; the flags exist because that is the honest boundary, not a limitation to engineer away.

explain — every layer's answer for one path

dynamic-config explain pool.max_size \
    --file config.toml --file secrets.toml \
    --key db --env APP_ --profile-env APP_ENV

Prints what every layer supplies for the path and which one wins — the same table AppConfig::explain(..) renders in code — except that values print as *** by default: a published diagnostic tool cannot ask its user to already know which paths are sensitive, so seeing values is the deliberate act, --show-values. --env-file adds .env layers, repeatable like --file.

diff — which paths moved between two documents

dynamic-config diff config-yesterday.toml config-today.toml --key db

Paths only, never values — the audit half of a change, holding the same line every other diagnostic holds.

Completions and the manual

dynamic-config completions bash > /etc/bash_completion.d/dynamic-config
dynamic-config man > /usr/local/share/man/man1/dynamic-config.1

MSRV 1.85; Beta, like every crate here — the flag surface is settled, and the diagnostics it prints hold the library's own guarantees.