toml

Parses/produces TOML, a simple hand-editable config format, into/from serde types. Used in crates/app/src/config.rs to read/write TrangoConfig at $XDG_CONFIG_HOME/trango/config.toml. Chosen for the same reason Cargo.toml itself uses it: easy for a user to open and fix by hand, unlike JSON or a binary format; integrates directly with serde, which trango already needed for this feature.

Pitfall

A missing or corrupt config file falls back to defaults rather than erroring — a persisted setting is a convenience, not something trango should refuse to start over.