Use the C++20 libraries to build actions, stream data through nodes, connect peers, and embed A11 directly in a native application. The components under cpp/a11/ are independently linkable, so an application can depend on the layers it uses. Python binds the same runtime objects with pybind11 and follows the same behavioural contract.

How the pieces fit together

A11 is a stack of independently linkable components:

concurrency — the fiber-aware task/future primitives (a11::Task, executors, schedulers) every asynchronous operation is built on. Awaitables returned across the runtime "resolve when ..." some work completes.
data — the wire value types (a11::data::Chunk, a11::data::NodeFragment, a11::data::WireMessage) and the a11::data::SerializationRegistry that maps application objects to and from chunks.
stores — a11::stores::ChunkStore, the ordered, appendable log that holds a stream's data, with ChunkStoreReader/ChunkStoreWriter cursors over it. The default LocalChunkStore keeps data in memory; the interface is a pluggable extension point.
nodes — a11::nodes::AsyncNode, the unit of streaming state (an ordered sequence of chunks, keyed by sequence number) that one side writes and another reads, optionally mirrored to a peer over a wire stream. NodeMap groups the nodes of a peer.
net — a11::net::WireStream, the transport abstraction, and its implementations (in-process, WebSocket/HTTP2, HTTP SSE, WebRTC) plus the signalling used to establish peer connections. A wire stream's delivery is unordered but synchronised on closure.
actions — a11::actions::Action, the schema-described unit of work whose typed input/output ports are async nodes, together with ActionRegistry and the ActionSchema family that describe an action's interface.
service — a11::service::Session, the connection-scoped runtime that attaches wire streams, dispatches incoming action calls against a registry, and tracks their lifetimes so a connection can drain and close cleanly.
obs — native OpenTelemetry tracing emitted directly from C++.

Where to start

Streaming and storage: a11::nodes::AsyncNode, a11::stores::ChunkStore.
Actions and dispatch: a11::actions::Action, a11::actions::ActionRegistry.
Networking: a11::net::WireStream, a11::service::Session.

For task-oriented walkthroughs shared by the language APIs, see the main A11 documentation. Build and linking instructions are in BUILDING.md.