Senior Full-Stack Developer (Platform Audit & Multi-Tenant Hardening) - PT - Worldwide

About the project

Kausmos is a live wedding-planning platform: planners manage guest lists across multiple events per wedding, send outreach via WhatsApp/SMS/email, and each guest gets a personalized RSVP link. The product is built and in market. This engagement is not net-new feature work — it's a senior technical audit of an existing production system.

What we need

• Full platform audit: code quality, architecture soundness, and security posture
• Verify multi-tenant isolation is correctly enforced — no cross-tenant data leakage across planners/weddings, guest links, RLS policies, and any Supabase-level access control
• Identify and prioritize gaps: correctness bugs, race conditions, auth/session issues, RLS misconfigurations
• Testing: assess current test coverage, add/strengthen tests where it matters most given the hour budget
• Deliver a clear, prioritized findings report (not just a fix-everything pass) — client needs guidance, not just a diff

Who we're looking for

• Senior full-stack engineer, comfortable owning an audit independently with minimal hand-holding
• Strong hands-on experience with Supabase/PostgreSQL, specifically Row Level Security and multi-tenant data isolation — this is not a "read the docs as you go" engagement
• Production experience with React + Node.js on Vercel
• Can communicate findings clearly to founder — plain-language risk summaries, not just ticket dumps
• Efficient: this is a capped-hours engagement, so time management and prioritization matter as much as technical depth
• Reliable: consistent availability and communication for the duration of the engagement

Deliverables

• Audit findings report
• Confirmation (with evidence) that multi-tenant isolation holds, or a documented list of gaps and fixes
• Test coverage added/improved for critical paths
• Recommendations for anything out of scope that the client should address next