Stability & Versioning

slate follows Semantic Versioning. This page describes which parts of the library are covered by versioning guarantees and what to expect across releases.

Public API surface

The following modules make up the supported public API:

Module	Purpose
slate	Shared types (DetsError, AccessMode, RepairPolicy, TableInfo) and helper functions (error_code, error_message, is_dets_file)
slate/set	Set tables — one value per key
slate/bag	Bag tables — multiple distinct values per key
slate/duplicate_bag	Duplicate bag tables — duplicate key-value pairs allowed

All public functions in these modules are covered by semver guarantees.

Internal surfaces

The Erlang FFI files (dets_ffi.erl and with_table_ffi.erl) are internal implementation details. They are not part of the public API and may change in any release without notice. Do not call FFI functions directly — use the Gleam module APIs instead.

Semver policy

Release type	What changes
Patch (e.g., 1.0.0 → 1.0.1)	Bug fixes only. No new features, no breaking changes.
Minor (e.g., 1.0.0 → 1.1.0)	Backward-compatible additions — new functions, new options. Existing code continues to compile and work.
Major (e.g., 1.0.0 → 2.0.0)	Breaking changes — removed or renamed functions, changed return types, added or removed type variants, new record fields.

Stable error codes

The strings returned by slate.error_code are stable across minor and patch releases. You can safely use them for programmatic matching — for example, in error-handling logic, logging, or metrics.

case slate.error_code(error) {
  "not_found" -> handle_missing()
  "access_denied" -> handle_permission_error()
  code -> log_unexpected(code)
}

The strings returned by slate.error_message are human-readable descriptions intended for display or logging. They may change in any release and should not be used for programmatic matching.

Diagnostics-only surfaces

The UnexpectedError(detail) variant of DetsError wraps unexpected Erlang error terms as a formatted string. The detail string is not a stable API contract — it may change across any release. error_message intentionally returns a generic message for this variant. Use error_code instead for reliable programmatic matching.

Upgrade guidance

• CHANGELOG.md — release history with detailed notes for every version.
• GitHub Releases — tagged releases with download links.

When upgrading across major versions, check the changelog for migration notes and breaking changes. Minor and patch upgrades should be drop-in replacements.