Installation

Compose

The queue stack is included automatically when selecting the queue stack during /ipa.compose. Run the compose skill:

/ipa.compose

Select the queue stack when prompted for stacks to include. The compose step generates Makefile targets, parameter overrides, and cross-stack wiring for the queue tier.

Configuration

Required Parameters

Parameter	Type	Description
Namespace	String	Project namespace prefix for resource naming. 1--12 characters, lowercase alphanumeric and hyphens, must start with a letter.
Environment	String	Deployment environment. Allowed values: dev, staging, prod.
ImageUri	String	Full ECR image URI including tag (e.g., 123456789012.dkr.ecr.us-east-1.amazonaws.com/repo:latest).
AuthIssuer	String	OIDC issuer URL for JWT validation (from Cognito IssuerUrl output).
AuthAudience	String	OIDC client ID for JWT audience validation (from Cognito UserPoolClientId output).

Optional Parameters

Parameter	Type	Default	Description
QueueName	String	jobs	Logical queue name. Physical name: {Namespace}-{Environment}-{QueueName}. 1--30 characters, lowercase alphanumeric and hyphens.
VisibilityTimeout	Number	300	Time in seconds a message is hidden after being received. Must exceed the worker Lambda timeout. Range: 0--43200.
MessageRetentionPeriod	Number	345600	Time in seconds messages are retained in the queue (default: 4 days). Range: 60--1209600.
MaxReceiveCount	Number	3	Number of receive attempts before a message is sent to the dead-letter queue. Range: 1--1000.
CreateDLQ	String	true	Whether to create a dead-letter queue for failed messages. Allowed values: true, false.
FunctionName	String	fn-worker	Worker Lambda function name suffix. 1--24 characters, lowercase alphanumeric and hyphens.
MemorySize	Number	512	Worker Lambda memory allocation in MB. Range: 128--10240.
Timeout	Number	300	Worker Lambda timeout in seconds. Range: 1--900.
ImageCommand	CommaDelimitedList	python,-m,sqs_handler	Worker container CMD override.
EnableJobsTable	String	false	Feature flag: create a DynamoDB jobs table. Allowed values: true, false.
AlarmSnsTopicArn	String	(empty)	SNS topic ARN for alarm actions. Leave empty to keep alarms in a disabled state.

Feature Flags

Flag	Default	Effect
EnableJobsTable	false	Creates a DynamoDB table ({Namespace}_{Environment}_jobs) with pay-per-request billing and SSE. Adds a conditional IAM policy granting the worker read/write access scoped to the table ARN.
CreateDLQ	true	Creates a dead-letter queue ({Namespace}-{Environment}-{QueueName}-dlq) with 14-day retention and SQS-managed encryption. Configures a redrive policy on the main queue with the specified MaxReceiveCount. Creates a DLQ depth alarm.

Wiring

Upstream (inputs from prepare stacks)

Queue Parameter	Source Stack	Source Output	Description
ImageUri	ECR	RepositoryUri	Container image URI for the worker Lambda.
AuthIssuer	Cognito	IssuerUrl	OIDC issuer URL for JWT validation.
AuthAudience	Cognito	UserPoolClientId	OIDC client ID for JWT audience validation.

Downstream (outputs consumed by backend)

Queue Output	Backend Parameter	Description
QueueUrl	SqsQueueUrl	SQS queue URL passed to the backend Lambda environment.
QueueArn	SqsSendQueueArns	SQS queue ARN used to grant the backend Lambda send permissions.

The compose step handles all wiring automatically. No manual cross-stack references are required.

Outputs

Output	Condition	Description
QueueUrl	Always	SQS queue URL. Consumed by the backend stack SqsQueueUrl parameter.
QueueArn	Always	SQS queue ARN. Consumed by the backend stack SqsSendQueueArns parameter.
QueueName	Always	Physical queue name ({Namespace}-{Environment}-{QueueName}).
WorkerFunctionArn	Always	Worker Lambda function ARN.
WorkerFunctionName	Always	Worker Lambda function name.
DlqUrl	CreateDLQ=true	Dead-letter queue URL.
DlqArn	CreateDLQ=true	Dead-letter queue ARN.
JobsTableArn	EnableJobsTable=true	DynamoDB jobs table ARN.
DashboardUrl	Always	Direct URL to the queue CloudWatch dashboard in the AWS Console.