Dasel is a command-line tool and library for querying, modifying, and transforming data across multiple structured formats.
Dasel solves the problem of working with heterogeneous data formats by providing a unified query syntax that works identically across JSON, YAML, TOML, XML, CSV, HCL, INI, and KDL. Rather than learning format-specific tools or writing separate parsing logic for each format, users write a single selector expression that applies to any supported format. The tool can extract values, modify them in place, delete entries, and convert data between formats, all through the same consistent interface. It supports recursive descent to search nested structures and conditional search operations to find matching values anywhere in a document.
Dasel suits developers and DevOps engineers who regularly manipulate configuration files or structured data in scripts and pipelines. It is particularly valuable when working with mixed-format environments where data needs to flow between JSON APIs, YAML configurations, TOML settings, and other formats. The tool integrates easily into shell scripts and command-line workflows, and it also provides a Go library for programmatic use in larger applications. The README does not compare it to alternatives, so no comparative positioning is available.
The project maintains active development with regular updates and bug fixes. The tool has comprehensive documentation covering installation, usage patterns, and advanced features. Shell completion support is built in for major shells including Bash, Zsh, Fish, and PowerShell. Prebuilt binaries are distributed for Linux, macOS, and Windows, reducing friction for users who do not want to build from source.
