.toml File — Tom's Obvious Minimal Language

TOML (Tom's Obvious Minimal Language) is a configuration file format created by Tom Preston-Werner (GitHub co-founder) in 2013, designed to be a minimal and unambiguous alternative to YAML and JSON for configuration. TOML uses an INI-like syntax with clear semantics — square brackets for sections (tables), dot notation for nested keys, and explicit typing for values including strings, integers, floats, booleans, dates, times, and arrays. TOML avoids YAML's implicit type conversion problems and JSON's lack of comments, providing a clean format specifically optimized for configuration files rather than general data interchange. TOML is the standard configuration format for Rust (Cargo.toml), Python (pyproject.toml per PEP 518), Hugo static site generator, and Netlify. The format supports inline tables, arrays of tables, multi-line strings, and literal strings without escape processing. TOML's specification is precise enough that implementations across different languages produce identical results, avoiding the interoperability issues that plague YAML. The TOML 1.0 specification was released in 2021, marking the format's stability for production use.