Crate guide

A reference table of the workspace crates, grouped by layer, so you can find the crate you need and know who it serves before you open src/lib.rs. This complements the architecture orientation, which explains the actor model and the dependency layering these crates fit into. For the model the code implements, see the Protocol Reference.

The Audience column is a hint, not a hard boundary: app-dev crates surface to people building apps, operator crates to people running nodes, and internal crates are workspace plumbing you touch when changing the core.

Note

Crate purposes are grounded in each crate’s src/lib.rs module docs and the workspace Cargo.toml. Where a crate has no module doc, the one-liner is inferred from its modules and the architecture map — treat those as orienting, not authoritative, and read the source before relying on a boundary.

App-facing SDK

What an application author compiles against, plus the host/guest boundary.

Crate	Audience	What it is	Key facts
sdk (+ sdk/macros)	app-dev	Proc-macro SDK for building CRDT apps: #[app::state], #[app::logic], #[app::event], #[app::migrate].	Compiles to WASM. Event handlers may run in parallel — handlers must be commutative, idempotent, and pure. Ships the TestHost unit-test harness.
prelude	internal	Common re-exports for ergonomic imports across crates.	Convenience surface; no logic of its own.
wasm-abi	internal	The WASM ABI shared between host and guest.	Holds schema, embed, normalize, validate, and downgrade of the app ABI.
sys	internal	Low-level system / host ABI bindings at the SDK–runtime boundary.	Thin type definitions; the contract the runtime’s host functions implement.

Protocol core

The deterministic engine: shared types, execution, and the unified causal log.

Crate	Audience	What it is	Key facts
primitives	internal	Core shared types used across the workspace.	ContextId, identities, blobs, CRDT, events, hashes. The layer everything converges on.
crypto	internal	Cryptographic primitives: keys, signing, hashing, shared-key derivation.	Underpins identity and delta signing.
runtime	internal	Wasmer + Cranelift WASM execution engine.	Builds a VMLogic per call, runs the exported method, returns an Outcome (return value, logs, events, storage delta). 50+ host functions.
dag	internal	Pure causal DAG for delta tracking with automatic dependency resolution.	No network or storage deps. Orders changes correctly even when messages arrive out of order.
op	internal	The one Op envelope for the unified causal log.	A data write, writer-set rotation, membership change, or policy change are all the same Op. Defines canonical id and scope_root hashing.
projection	internal	ScopeState — the single deterministic projection of a scope’s op-log.	Same ops, any order, deduped by id, yield the same state and root. acl_view_at resolves the causal-honor authorization view.
authz	internal	The one authorization fold over the op-log.	authorize is a single match over the op payload against an AclView resolved at the op’s causal cut — the forward-only / causal-honor property.
op-adapter	internal	Transitional bridge mapping per-plane operation types onto the unified OpPayload.	Explicitly transitional — slated for deletion once everything runs on the unified payload. Treat its boundaries as moving.

Caution

op / projection / authz / op-adapter are part of the in-progress unified causal log migration. Their exact boundaries are moving targets — check the source before relying on them.

Governance

Local (no-chain) group governance.

Crate	Audience	What it is	Key facts
governance-types	internal	Signed group-operation types for local governance (no chain).	A leaf crate, so governance-store can depend on the op types without pulling in actix.
governance-store	internal	Apply pipeline, broadcast / ack flow, metrics, and notifications for local group governance.	Extracted from calimero-context; callers still reach it via re-export shims in that crate.

Networking & node

The running node: orchestration, contexts, transport, and config.

Crate	Audience	What it is	Key facts
node (+ node/primitives)	internal	Node runtime coordinating sync, storage, networking, and events.	Hosts the NodeManager actor, the SyncManager task, and the GarbageCollector. Owns delta handling and blob caching.
context (+ context/primitives)	internal	The ContextManager actor: contexts, groups, and per-namespace governance DAGs.	30+ message handlers covering execution, governance, membership, and upgrades.
network (+ network/primitives)	internal	The NetworkManager actor wrapping the composed libp2p behaviour stack.	gossipsub, Kademlia, mDNS, relay, rendezvous, hole-punching, streams. Moves opaque bytes only — never imports app types.
config	operator / internal	Node configuration (config.toml) types and loading.	Includes the libp2p network identity config.

Storage

Persistence: the CRDT collections down to the key-value backend.

Crate	Audience	What it is	Key facts
storage	app-dev / internal	CRDT storage collections and the interface over the underlying store.	UnorderedMap / UnorderedSet / Counter / registers; the per-entity merge that drives convergence. Ships the converge property-test harness.
storage-macros	app-dev / internal	Derive macros that wire app state into the storage subtree.	Derives AtomicUnit and friends so #[app::state] structs become storage entities.
store	internal	Column-family key-value abstraction over RocksDB via the Database trait.	Typed keys with compile-time size / column guarantees. Sibling crates add the RocksDB impl, blob store, and at-rest encryption.

Note

Three sibling crates round out the storage backend: store/impl/rocksdb (the RocksDB Database implementation), store/blobs (calimero-blobstore for large binaries), and store/encryption (optional transparent AES-GCM at rest).

Server & tooling

External surfaces, auth, attestation, and the binaries.

Crate	Audience	What it is	Key facts
server (+ server/primitives)	operator / internal	Single Axum HTTP server mounting all public surfaces.	Admin REST, JSON-RPC 2.0, WebSocket, SSE, Prometheus metrics, embedded dashboard SPA. Holds no business logic — delegates to clients.
auth (mero-auth)	operator	Forward-auth service: JWT issue / verify, pluggable providers.	Runs embedded in the server or behind a reverse proxy. user_password is the only shipped provider.
client	app-dev	Trait-based client library for talking to Calimero APIs.	Abstract interfaces for auth, token storage, and API comms; used by tooling and integrations.
meroctl	operator / app-dev	The operator / developer CLI.	Drives nodes: install contexts, call methods, inspect state.
merod	operator	The node daemon binary.	merod --node <name> init then run. Supports --no-default-features for a local-only init build.
tee-attestation	operator / internal	Platform-agnostic TEE attestation generation and verification.	Generates / verifies TDX quotes (Linux with TDX); mock attestation on other platforms for development.

Build / util

Shared plumbing for build scripts and runtime glue.

Crate	Audience	What it is	Key facts
build-utils	internal	Shared build-script utilities for Calimero binaries and crates.	Workspace version reading and git metadata, so build scripts stay DRY.
utils (utils/actix)	internal	Actix helper utilities reused across the actor crates.	Small glue layer for the actor-model code.

Related

Architecture orientationThe actor model and the dependency layering these crates fit into.

Protocol ReferenceThe signed-op DAG and deterministic fold the codebase implements.