Application Integration on 🏠

11. Error Handling & Retry Patterns

Mon, 01 Jan 0001 00:00:00 +0000

Error Handling & Retry Patterns — Cross-Cutting Theme#

Before diving into individual services, it’s worth internalizing a set of patterns that appear repeatedly across SQS, SNS, Lambda, API Gateway, DynamoDB, Kinesis, Step Functions, and EventBridge. The exam tests these concepts in context — meaning you’ll see them embedded in scenario questions about specific services — so understanding them as a unified mental model first will save you significant effort later.

12. SQS

Mon, 01 Jan 0001 00:00:00 +0000

SQS (Simple Queue Service)#

Amazon Simple Queue Service (SQS) is a fully managed message queuing service that lets you decouple the components of a distributed application. The core problem it solves is temporal coupling: without a queue, if a downstream service (consumer) is slow, overloaded, or temporarily unavailable, the upstream service (producer) either fails or has to wait. SQS breaks that dependency — producers drop messages into the queue and move on, consumers process at their own pace. 🔗

13. SNS

Mon, 01 Jan 0001 00:00:00 +0000

Amazon Simple Notification Service (SNS) 🔗 is a fully managed pub/sub messaging service. Where SQS decouples a single producer from a single consumer, SNS solves a different problem: broadcasting one message to many recipients simultaneously. A single Publish call to an SNS topic can trigger an email notification, invoke a Lambda function, and drop a copy of the message into an SQS queue — all at once. This makes SNS the natural choice for fan-out architectures and alert pipelines.

14. EventBridge

Mon, 01 Jan 0001 00:00:00 +0000

EventBridge#

Amazon EventBridge is a serverless event bus that connects AWS services, your own applications, and third-party SaaS platforms by routing events from producers to consumers based on rules you define. It exists to solve a fundamental integration problem: how do you let dozens of services react to things that happen in your system without coupling them together? Before EventBridge, you’d wire services directly — Lambda calls SQS, SQS triggers Lambda, Lambda calls another Lambda — creating brittle chains that are hard to change and harder to debug. EventBridge inverts this: producers emit events onto a bus, and any number of consumers subscribe to exactly the events they care about. Neither side knows about the other.

15. Kinesis Data Streams

Mon, 01 Jan 0001 00:00:00 +0000

Kinesis Data Streams#

Modern applications often generate data faster than any single consumer can process it — user clickstreams, IoT sensor readings, application logs, financial transactions. Amazon Kinesis Data Streams 🔗 exists to solve exactly this problem: it lets you ingest large volumes of real-time data, durably store it, and allow one or more consumers to process it independently at their own pace. Unlike SQS, where a message is consumed and gone, Kinesis retains records in order for a configurable window, making it ideal for replay, auditing, and parallel processing by multiple consumers.

16. Step Functions

Mon, 01 Jan 0001 00:00:00 +0000

Step Functions#

Modern applications rarely do just one thing — they chain together multiple operations: validate input, write to a database, call an external API, send a notification, and handle failures at each step. The naive approach is to wire these steps together inside Lambda functions, where one function calls another and so on. This creates tightly coupled, fragile chains that are hard to debug, retry, or modify. AWS Step Functions solves this by letting you define your workflow as a state machine — a visual, auditable graph of steps and transitions that AWS manages for you. You describe what should happen and in what order; Step Functions handles the execution, retries, error handling, and state passing between steps. 🔗

Application Integration on 🏠

11. Error Handling & Retry Patterns

Error Handling & Retry Patterns — Cross-Cutting Theme#

12. SQS

SQS (Simple Queue Service)#

13. SNS

SNS (Simple Notification Service)#

14. EventBridge

EventBridge#

15. Kinesis Data Streams

Kinesis Data Streams#

16. Step Functions

Step Functions#