Implement passwordless login using WebAuthn passkeys.
WebAuthn Passkey Engineer
WebAuthn, FIDO2, Cross-Platform Security
Best for
- ▸Implementing WebAuthn passkey registration and authentication flows in web applications
- ▸Migrating existing password-based authentication to support passkeys while maintaining fallback options
- ▸Designing cross-device authentication flows using FIDO2 hybrid transport with QR codes
- ▸Configuring conditional UI for username-less login with resident keys
What you'll get
- ▸Detailed code implementation for WebAuthn registration ceremony with proper challenge generation, credential options configuration, and server-side validation steps
- ▸Cross-platform deployment strategy covering browser support matrices, platform authenticator capabilities, and fallback authentication methods
- ▸Security architecture recommendations for credential storage, user verification requirements, and attestation validation policies
Details about your current authentication stack, target platforms, user base type (consumer/enterprise), and specific WebAuthn implementation challenges or requirements.
Step-by-step implementation guidance, code examples for registration/authentication ceremonies, security configuration recommendations, and troubleshooting solutions for cross-platform passkey deployment.
What's inside
“You are a WebAuthn Passkey Engineer. You implement passkey-based authentication across consumer and enterprise applications, covering the full lifecycle from credential strategy through phased migration and account recovery. - **Origin-binding enforcement:** You treat RP ID validation, origin matchi...”
Covers
Not designed for ↓
- ×General OAuth/SAML identity provider integration or enterprise SSO setup
- ×Mobile app biometric authentication without WebAuthn (native Touch ID/Face ID only)
- ×Password manager development or browser extension security
- ×Smart card or traditional PKI certificate authentication systems
SupaScore
89.98▼
Evidence Policy
Standard: no explicit evidence policy.
Research Foundation: 7 sources (4 official docs, 2 web, 1 industry frameworks)
This skill was developed through independent research and synthesis. SupaSkills is not affiliated with or endorsed by any cited author or organisation.
Version History
v6.0 wave-1 repair: re-distilled from masterfile/v2 (truncation incident 2026-06, delta-first rules)
v5.5 distilled from v2 via Claude Sonnet
Pipeline v4: rebuilt with 3 helper skills
Initial release
Works well with
Need more depth?
Specialist skills that go deeper in areas this skill touches.
Common Workflows
Secure Authentication Modernization
Complete migration from legacy authentication to passwordless with comprehensive access controls and governance
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