Module state 

Pluggable state backend (StateBackend trait + impls). Checkpoint-artifact backend abstraction. Two concrete backends: InProcessBackend for embedded single-process runs, and ObjectStoreBackend for anything durable (local filesystem via file://, or S3/GCS/Azure).

Re-exports

pub use backend::CheckpointAttempt;

pub use backend::CheckpointAttemptRelation;

pub use backend::CheckpointSealInventory;

pub use backend::SealedCommitDescriptor;

pub use backend::SealedCommitDescriptorWriter;

pub use backend::SealedVnodePartial;

pub use backend::SealedVnodeWriter;

pub use backend::StateBackend;

pub use backend::StateBackendDurability;

pub use backend::StateBackendError;

pub use config::StateBackendBuildError;

pub use config::StateBackendConfig;

pub use in_process::InProcessBackend;

pub use object_store::ObjectStoreBackend;

pub use vnode::key_hash;

pub use vnode::owned_vnodes;

pub use vnode::owners_per_domain;

pub use vnode::peer_owners;

pub use vnode::rendezvous_assignment;

pub use vnode::InvalidKeyGroupCount;

pub use vnode::KeyGroupCount;

pub use vnode::Locality;

pub use vnode::NodeId;

pub use vnode::VnodeAssignmentReadGuard;

pub use vnode::VnodeAssignmentSnapshot;

pub use vnode::VnodeLifecycleState;

pub use vnode::VnodeRegistry;

pub use vnode::DEFAULT_CLUSTER_KEY_GROUP_COUNT;

pub use vnode::LOCAL_KEY_GROUP_COUNT;

pub use vnode::MAX_KEY_GROUP_COUNT;

pub use vnode::PARTITIONING_ABI_VERSION;

Modules

backend

The StateBackend trait persists per-checkpoint-attempt vnode artifacts and exposes an exact-attempt durability seal. It is not the hot keyed-state implementation used while operators process records.

config

StateBackendConfig: tagged enum selecting storage for checkpointed vnode artifacts. Three shapes: in_process, local (filesystem path), object_store (S3/GCS/Azure/file URL).

in_process

InProcessBackend — non-durable checkpoint-artifact storage backed by an in-memory hashmap. Used for tests and embedded single-process runs.

object_store

ObjectStoreBackend — durable partial-state storage backed by any object_store implementation (S3, GCS, Azure, LocalFileSystem).

vnode

VnodeRegistry — runtime-configurable virtual node topology.