# Everruns 0.20.0: Register capabilities on a running runtime

> A2A delegation in the everruns crate becomes an opt-in feature, and a running Framework runtime can register new capabilities without a restart.

Source: <https://everruns.com/docs/changelog/2026-08-19-everruns-0-20-0/>

Date: 2026-08-19
Products: Platform, Framework, CLI
Category: Release

## Highlights

* **Register capabilities on a running runtime**: A host holding `Arc<InProcessRuntime>` can now make a capability discovered after composition resolvable without rebuilding the runtime, via `register_capability`/`is_capability_registered`. Registration stays separate from activation, and readers always see a consistent registry snapshot ([#3224](https://github.com/everruns/everruns/pull/3224)).
* **A2A delegation is now opt-in**: Outbound A2A delegation moved behind a new `a2a` Cargo feature, off by default, so the standard build no longer drags a second HTTP/TLS stack into consumers that only run the local runtime. Hosts that delegate to remote A2A agents enable the `a2a` feature explicitly ([#3221](https://github.com/everruns/everruns/pull/3221)).

## In the changelog

* [A2A delegation in the everruns crate is now an opt-in feature](https://everruns.com/docs/changelog/2026-08-18-a2a-delegation-opt-in/)
* [Register a capability on a running Framework runtime](https://everruns.com/docs/changelog/2026-08-19-register-capabilities-running-runtime/)

Before upgrading, read the breaking changes: [A2A delegation in the everruns crate is now an opt-in feature](https://everruns.com/docs/changelog/2026-08-18-a2a-delegation-opt-in/).

See the [GitHub release](https://github.com/everruns/everruns/releases/tag/v0.20.0) and the [full release notes](https://github.com/everruns/everruns/blob/main/CHANGELOG.md#0200---2026-08-19) for every pull request in this version.