Chatto uses per-file SPDX license metadata following the REUSE specification. The canonical machine-readable license boundary is in REUSE.toml.
The default repository license is the GNU Affero General Public License version
3 or any later version (AGPL-3.0-or-later). This covers the Chatto server,
CLI, and bundled server release artifacts unless a more specific license is
declared.
Apache-2.0 exceptions are used where permissive reuse is intentional. These
include the independently versioned pkg/events, pkg/natsruntime,
pkg/datacrypto, and pkg/appconfig shared framework modules, the
framework-neutral packages/lingua internationalisation runtime, the
standalone frontend source and image, public protocol/API definitions,
generated TypeScript API client/types, documentation, and deployment examples.
The shared modules remain explicitly pre-1.0; their permissive license does not
imply API stability.