AWS SQS

Amazon Simple Queue Service (SQS) is a fully managed message queuing service for decoupling microservices. It offers two queue types: Standard (best-effort ordering, at-least-once delivery) and FIFO (exactly-once, ordered).

Core Concepts

• Standard Queue — unlimited throughput, at-least-once delivery, best-effort ordering
• FIFO Queue — exactly-once processing, strict ordering, 3000 msg/s with batching
• Visibility Timeout — period a message is hidden after being received
• Dead-Letter Queue (DLQ) — destination for messages that fail processing
• Message Group ID — FIFO ordering key for parallel processing within a queue
• Long Polling — reduces empty responses and API costs

Creating Queues

# Create a standard queue
aws sqs create-queue \
  --queue-name order-processing \