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# Stability and versioning

C+ is **feature-frozen at v0.0.22**. The contextual builder-block DSL was
the last addition to the language surface. From here the core language
takes **bug fixes only** — no new syntax, no new semantics. New capability
ships in packages and tooling, never in the core language.

This page states what that freeze guarantees, what is still allowed to
change, and how packages version on their own cadence. The
[language specification](/docs/spec) is the normative description of the
frozen surface.

## What the freeze guarantees

- **No new language surface.** The grammar, the keyword set, the type and
  ownership systems, and the desugarings described by the
  [specification](/docs/spec) are fixed. A future release will not add a
  keyword, an operator, a new kind of item, or a new implicit behaviour to
  the core language.
- **Source compatibility.** A program that the v0.0.22 compiler accepts is
  intended to keep compiling, with the same meaning, on later v0.0.x
  compilers. If a later release changes whether a given program compiles,
  that is a bug fix bringing the compiler in line with the specification —
  not a feature — and it is called out as such.
- **A stable target for tools and agents.** Because the surface no longer
  moves, the grammar, the `cpc query` / `cpc mcp` code graph, the
  [error codes](/docs/error-codes), and the `/llms.txt` snapshots describe
  a language that stays put. Tooling built against v0.0.22 does not chase a
  moving syntax.

## What can still change

The freeze is on *language surface*, not on the implementation. The
following are expected to keep improving and are not considered breaking:

- **Bug fixes.** Where the compiler and the [specification](/docs/spec)
  disagree, the compiler is corrected to match the spec (or, rarely, the
  spec is corrected to match the compiler). That can mean a program that
  was wrongly accepted is later rejected, or one that was wrongly rejected
  later compiles.
- **Diagnostics.** Error and warning *wording*, spans, notes, and
  machine-applicable suggestions improve freely. The stable
  [error codes](/docs/error-codes) and their meanings are the contract;
  the exact message text is not.
- **Performance and code generation.** Optimisation, codegen quality, and
  ABI lowering improve over time. The language asks for no runtime tax for
  its safety, and that work continues under the freeze.
- **Tooling.** `cpc` subcommands (`build`, `check`, `run`, `test`, `fmt`,
  `doc`, `query`, `mcp`, `lsp`) and the editor surface evolve and gain
  features — this is where most ongoing work lands.
- **Targets.** Support for additional [targets](/docs/targets) and
  cross-compilation back-ends can be added; adding a target does not change
  the language.
- **The standard library and packages.** `stdlib` and every package under
  `vendor/` evolve on their own cadence (see below).

## The compiler is the authority

The [specification](/docs/spec) is verified against `cpc` and its test
suite, but where the two ever disagree the **compiler wins** — run
`cpc check` or `cpc build` and trust the diagnostic. The in-repo test
suite is the executable conformance record. If you find a case where the
compiler and the spec disagree, that is a bug worth
[reporting](https://github.com/netdur/cplus).

## Packages version independently

The freeze is what makes the package-first model work. Capability that
would once have been a language feature now lives in a package, and each
package carries **its own version** and moves at its own pace:

- A package declares its dependencies and their versions in `Cplus.toml`
  and is resolved under `vendor/`. See
  [Modules and packages](/docs/modules-and-packages) and the
  [package manager](/docs/package-manager).
- A new package, or a new release of an existing one, adds capability
  without touching the language. The compiler that builds it is the same
  frozen v0.0.22 surface.
- This is the intended path for everything additive: UI builders, FFI
  bindings, numeric kernels, embedded peripherals. The
  [packages index](/docs/packages) lists what ships today.

## Documentation versioning

The manual you are reading **tracks the current release**. Every release is
also archived: older versions stay available at `/docs/{version}` and are
**never removed or collapsed** — they are intentional archives, not stale
pages. When you cite the manual, cite the version. `/docs` and
`/llms.txt` are authoritative for the latest release (v0.0.22).

For *why* the language is frozen and why the design is the way it is, see
the [design FAQ](/docs/faq).
