CIAM (Customer Identity & Access Management) is where IAM meets real product constraints: conversion rates, support costs, fraud, privacy regulation, and at-scale reliability.
This page is vendor-agnostic by design: the concepts apply whether you use a homegrown stack or a CIAM platform.
The goal
Registration is not “create a user.” It is a risk-managed funnel:
- Get the minimum viable data to start a session
- Establish an account binding you can rely on later
- Avoid creating an easy fraud API
Design patterns
Progressive onboarding
- Start with email/phone + verification
- Delay higher-friction steps (KYC, address, payment) until there is a reason
Double opt-in where it matters
- Email verification before enabling high-risk actions
- Rate-limit verification resend flows
Common pitfalls
- Treating registration endpoints as public APIs without abuse controls
- Using “email exists” errors that enable enumeration
- Storing raw PII before you have a clear retention purpose
Checklist
- Bot protection / rate limiting
- Enumeration-safe messaging
- Verified email/phone signals
- Audit trail (when + how the account was created)