Senior Full-Stack Engineer (Freelance)

About the Project

An early-stage healthcare startup needs a freelance engineer to stabilize an existing credentialing and job-matching platform before launch.

The product is largely built with AI assistance. You'll work directly with the founder to execute an established plan, fix issues, and prepare it for broader use.

What You'll Do

• Fix broken or inconsistent workflows across the frontend, backend, database, background jobs, storage, and integrations.
• Refactor existing code without disrupting working functionality.
• Improve access controls, profile relationships, and sensitive healthcare data handling.
• Stabilize document uploads, processing, downloads, and AI extraction workflows.
• Diagnose regressions and verify fixes with automated tests, logs, and production evidence.
• Prioritize launch blockers and preserve existing security and privacy safeguards.

Who We're Looking For

Must Have

• 5–8+ years of professional software development, with experience stabilizing and launching existing SaaS products.
• 3+ years building production TypeScript and React applications, plus strong Node.js experience.
• Ownership of at least one SaaS product through launch and post-release operations.
• PostgreSQL and ORM experience.
• REST API design, validation, authentication, authorization, and contract management.
• Background jobs, queues, retries, idempotency, leases, and failure recovery.
• Secure file handling, object storage, PDFs, and document processing.
• AI document extraction pipelines with human review and correction.
• Vitest, Playwright, integration testing, and browser debugging.
• Monorepo or multi-package workspace experience.
• Deployment, observability, performance analysis, and incident response.

You should be comfortable inheriting a complex codebase: understand the architecture before changing it, trace issues across systems, and fix underlying causes while preserving existing controls.

Nice to Have

• React Query, component libraries, and Drizzle ORM.
• Healthcare, credentialing, staffing, HR, insurance, or regulated SaaS experience.
• HIPAA-related development, provider licensing, or professional verification workflows.
• Multi-tenant applications, complex permissions, or marketplace products.
• AWS/S3-compatible storage, Stripe, email, messaging, or external registry integrations.
• Accessibility, responsive design, security reviews, and threat modeling.

Tools & Technologies

• Application: TypeScript, Node.js, React
• Data & APIs: PostgreSQL, ORMs, REST
• Testing: Vitest, Playwright
• Processing: Background jobs, queues, object storage, PDFs, AI document extraction

Hiring Process

• Initial interview to discuss relevant experience and fit.
• Possible codebase review after signing an NDA.
• Possible discussion of your technical assessment and stabilization approach.
• Arc will coordinate interviews, contracts, and next steps.

Ready to Apply?

If you've helped bring an existing SaaS product to launch and are comfortable working through a complex codebase, we'd like to hear from you. You don't need every preferred qualification to apply.