Building a cross-site SSO layer to unify login across a main site and ticketing subdomain
A custom WordPress plugin that enabled single sign-on between two sites, reducing friction for ticket purchase and account access.
Date
Nov. 25 - Dec. 25
Client
Global organisation (event ticketing)
Category
Authentication, WordPress plugins, integrations
PLACEMENT
Production platform (main site + ticketing subdomain)
The Situation.
A global organisation ran its primary website on one domain, with ticket sales handled on a separate subdomain. Users expected one account, but the split created repeated login friction and support overhead.
The Challenge
The requirement was straightforward on paper, one login across both sites. In practice, it needed to be secure, reliable, and compatible with existing WordPress constraints.
Key problems to solve:
Making authentication seamless without confusing users
Handling session and state across two WordPress installs
Ensuring the ticketing flow stayed stable under real purchase behaviour
Working across stakeholders in different time zones
What I implemented.
SSO plugin design Built a custom plugin to coordinate authentication between the main site and the ticketing subdomain.
Token and session handling Implemented a secure handshake approach so users could move between sites without repeated logins.
User state consistency Ensured account states and permissions remained aligned across both environments.
Practical rollout approach Shipped changes safely with controlled testing, limiting the risk to live ticket sales.
The Outcome.
Users experienced a more continuous journey between browsing and ticket purchase, with fewer authentication issues and less support intervention.