## ADDED Requirements

### Requirement: Key-Value Store Interface
The system SHALL define an `IKeyValueStore` interface with operations: get, put, query, delete, scan, batchGet, and batchWrite, parameterized by key schema. The interface SHALL be defined in terms of capabilities, not AWS API shapes.

#### Scenario: Interface implementable by multiple backends
- **WHEN** a provider implements `IKeyValueStore`
- **THEN** it SHALL be implementable by SQLite (local dev), PostgreSQL (production VPS), or DynamoDB (production AWS) without changes to the interface

### Requirement: Queue Interface
The system SHALL define an `IQueue` interface with operations: send, receive, delete, and deadLetter, parameterized by FIFO mode, visibility timeout, and DLQ configuration.

#### Scenario: Interface supports queue semantics
- **WHEN** a provider implements `IQueue`
- **THEN** it SHALL support message send, receive with visibility timeout, message deletion, and dead-letter routing

### Requirement: Object Store Interface
The system SHALL define an `IObjectStore` interface with operations: put, get, delete, and list, parameterized by event notification configuration.

#### Scenario: Interface supports object operations
- **WHEN** a provider implements `IObjectStore`
- **THEN** it SHALL support storing, retrieving, deleting, and listing objects by key, and emitting event notifications on changes

### Requirement: Event Bus Interface
The system SHALL define an `IEventBus` interface with operations: publish, subscribe, and matchRules, parameterized by event patterns.

#### Scenario: Interface supports event routing
- **WHEN** a provider implements `IEventBus`
- **THEN** it SHALL support publishing events, subscribing to event patterns, and matching events against rules

### Requirement: State Machine Interface
The system SHALL define an `IStateMachine` interface that supports starting executions, tracking state transitions, and handling retries and error catching.

#### Scenario: Interface supports workflow execution
- **WHEN** a provider implements `IStateMachine`
- **THEN** it SHALL support executing a defined state machine with input, tracking transitions between states, and handling errors

### Requirement: Compute Interface
The system SHALL define an `ICompute` interface with an invoke operation accepting event, context, and timeout parameters, parameterized by runtime, handler path, and environment variables.

#### Scenario: Interface supports handler invocation
- **WHEN** a provider implements `ICompute`
- **THEN** it SHALL support invoking a handler function with an event payload and context, enforcing timeout, and returning the result

### Requirement: Provider Lifecycle
Each provider interface SHALL include start, stop, and healthCheck lifecycle operations so that LDK can manage provider instances during environment startup and shutdown.

#### Scenario: Provider startup and shutdown
- **WHEN** LDK starts the local environment
- **THEN** each provider instance SHALL be started via its start method and stopped via its stop method on shutdown, with healthCheck available to verify readiness

### Requirement: Interface Package Independence
The provider interfaces SHALL be published as a standalone package (`ldk-interfaces`) that depends on no other LDK packages, enabling independent provider development.

#### Scenario: Provider depends only on interfaces
- **WHEN** a developer creates a new provider implementation
- **THEN** they SHALL only need to depend on `ldk-interfaces`, not on `ldk-core` or `ldk-cli`
