Cargo feature matrix

Important

Dependency examples use 12.0.0-rc.1, the planned first v12 RC. Do not request it from crates.io before it is published; use path dependencies from this source checkout during development.

This page is the public feature contract for the 16 packages in the Rullst release train. The package manifests remain the machine-readable source of truth. The matrix explains the behavior those names select in v12 and makes the default build visible before an application adopts optional integrations.

Cargo features are additive across a dependency graph. An application can disable a package’s defaults at the dependency edge, but it cannot disable a feature enabled by another dependency. Inspect the final selection with:

cargo tree -e features

The release gates compile every package with no default features, every public umbrella feature in isolation, representative domain-package boundaries, and the complete workspace with all features. The isolated umbrella list is checked automatically against rullst/Cargo.toml, so a newly added public feature cannot silently escape the matrix. See check-feature-boundaries.sh for the exact individual checks.

Umbrella crate: rullst

The default rullst dependency enables orm and queue-sqlite. Applications that only need the HTTP runtime can opt out:

[dependencies]
rullst = { version = "12.0.0-rc.1", default-features = false }

The three strict-* backend features are supported as single selections. Feature unification can activate more than one; the current deterministic precedence is PostgreSQL, then MySQL, then SQLite. Do not depend on that precedence as backend negotiation. Select one strict backend in an application, or select none to use SQLx Any.

Shared-local SQLite composition profile

A bounded single-host application may compose the following umbrella features over one file-backed SQLite URL:

[dependencies]
rullst = { version = "12.0.0-rc.1", default-features = false, features = [
  "auth-sqlite",
  "capital-quota-sql",
  "mail-sqlite",
  "messaging-sqlite",
  "oauth-sqlite",
  "queue-sqlite",
] }

The stores use distinct fixed table namespaces. Initialize/check them sequentially, keep application readiness false until every required component is healthy, and reuse exactly the same URL, quotas, namespaces, and keys after restart. Close every handle before file-level backup or restore. The dedicated facade_recovery test proves restart, idempotency, encrypted-secret plaintext absence, queue recovery, aggregate readiness, and isolated fail-closed corruption for this exact profile.

Sharing the file is not a cross-domain transaction or a multi-host design. The host still owns permissions, encryption-key custody, a consistent whole-file backup procedure, recovery drills, contention policy, and domain authorization. Prefer separate databases when failure isolation or write throughput is more important than simple local operation.

Runtime and data crates

rullst-core

Default features: none.

Core’s process-local Radar and span collector do not require telemetry. That feature is specifically for OpenTelemetry/OTLP integration. The rullst.client v1 codec and bounded #[server_function] transport are available without a feature flag; only the explicit generated route exists on native targets, while the same annotated function becomes its Wasm caller. Identity, authorization and tenant policy remain application layers.

rullst-orm

Default features: none. With no strict-* feature, public pool and database aliases use SQLx Any.

The strict backend selection rules and precedence are the same as the umbrella crate. SQLx drivers remain implementation dependencies; strict-* selects concrete public types and query paths rather than acting as a driver download switch.

The Polyglot features expose capability-specific APIs under rullst_orm::polyglot; they do not participate in a shared cross-backend transaction. The base deterministic document store and the MongoDB/SurrealDB adapters implement DocumentInventory for an application-operated bounded snapshot/restore contract; it does not supply online isolation or managed backup. Turso can additionally be selected explicitly by #[orm(backend = "turso")] and the blank/API scaffold. See the Polyglot Persistence guide.

rullst-orm-macros

Default features: none. #[derive(Orm)] uses a fail-closed structured parser: unknown/duplicate options, missing persisted targets, conflicting relations, unsafe identifiers, and SQLx mappings that generated persistence cannot honor are compile errors. The exact derive grammar and its raw soft-delete-expression boundary are defined in the packaged crate README and the SST.

rullst-connect

Default features: none. Provider clients and framework-independent OAuth/OIDC types remain available without a web-framework adapter.

rullst-messaging

Default features: none. The deterministic process-local broker, versioned envelope, idempotency, consumer groups, leases, retry, dead-letter, and purge contracts are available without optional dependencies. Remote broker adapters are not implemented and therefore are not represented by placeholder features.

rullst-iot

Default feature: std.

rullst-capital

Default feature: axum.

rullst-mail

Default features: none. HTTP mail providers remain available without SMTP.

rullst-auth

Default features: none.

The umbrella crate exposes these as auth-jwt and auth-sqlite; both enable auth, while auth-sqlite also enables auth-jwt.

rullst-security

Default features: none.

The umbrella crate exposes this as security-redis, which also enables security.

Dashboard crates

rullst-nexus and rullst-studio both have no default features and expose the same database selection boundary:

Use the same single-selection rule described for rullst-orm.

Packages without optional features

These packages have no public optional Cargo features in v12:

No optional feature does not mean that a provider is contacted automatically. External integrations still require explicit runtime configuration and use the documented deterministic offline behavior for empty or mock_* credentials.

Selection recipes

Minimal HTTP runtime:

rullst = { version = "12.0.0-rc.1", default-features = false }

SQLite application using the release default:

rullst = "12.0.0-rc.1"

PostgreSQL application with explicit domain integrations:

rullst = {
    version = "12.0.0-rc.1",
    default-features = false,
    features = ["strict-postgres", "auth", "security", "telemetry"]
}

Embedded IoT model without the standard library:

rullst-iot = { version = "12.0.0-rc.1", default-features = false }

Experimental IoT fixtures are deliberately separate:

rullst-iot = {
    version = "12.0.0-rc.1",
    default-features = false,
    features = ["experimental-simulators"]
}