Learn

Idempotency is essential for reliable distributed systems. When networks fail and clients retry requests, idempotency prevents duplicate transactions—no double charges, no duplicate orders.

Key Concepts

Why Idempotency Matters

Every API that processes payments, creates orders, or modifies state needs idempotency. Without it, network failures and client retries create duplicate transactions. Learn why →

Duplicated vs Repeated Operations

Idempotency protects against duplicates from retries while allowing legitimate repeated operations. Use a different idempotency key for each distinct business operation. Learn the difference →

Client Key Strategies

How should you generate idempotency keys? Learn patterns for managing keys in your client applications. See strategies →

IETF Specification

This library implements the IETF draft standard for idempotency keys. Understanding the spec helps you implement idempotency correctly and interoperate with other systems. Read the spec compliance guide →

What You'll Learn

• The problem duplicates create in distributed systems
• How the idempotency-key pattern works
• What the IETF specification requires
• Implementation details for each requirement