Full-stack experienced developer needed

I am looking for a senior full-stack software engineer with experience auditing and improving existing applications, ideally with: Node.js, TypeScript and Express. PostgreSQL and Drizzle ORM. Expo and React Native, if applicable to the current build. Application security, authentication and permissions. Software testing, deployment and production readiness. Payment integrations and subscription systems, if applicable. Experience with education, behavioral health or SaaS products is a plus. Initial scope of work 1. Review the existing application Examine the current codebase, architecture, database and integrations. Identify the major components and how they interact. Document any technical limitations, dependencies or significant risks. Assess whether the existing architecture is suitable for the intended pilot. 2. Create a feature inventory For every major feature, document: Feature name and purpose. Intended user and expected behavior. Current implementation status. Whether it has been tested. Bugs, dependencies or missing functionality. Recommendation: keep, fix, complete, defer or remove. 3. Test the application Test key user journeys and existing functionality. Identify reproducible bugs and incomplete workflows. Evaluate error handling, reliability and usability. Document findings and their severity. 4. Conduct a security review Review authentication, authorization and access controls. Check how credentials, API keys and environment secrets are handled. Assess database security, data exposure risks and backup practices. Review payment-related security if payment features are implemented. Identify critical issues that must be addressed before a pilot. 5. Recommend a minimum viable pilot Identify which existing features are essential for the first pilot. Separate essential fixes from optional enhancements. Explain what can reasonably wait until a later version. Identify any additional privacy, compliance or technical requirements relevant to the intended users and data. 6. Provide a written technical report and estimate The final deliverables should include: Feature inventory and implementation status. Prioritized bug and security findings. Recommended minimum pilot scope. Proposed order of work. Estimated time and cost for the recommended fixes and next development phase. Key risks, assumptions and outstanding questions.