Senior Full-Stack Engineer (Business Workflow Platforms) - 21906

Senior Full-Stack Engineer — Business Workflow Platforms

Location: Remote · Must work core hours in U.S. time zones

Employment Type: Full-time · Available as contract (Talent on Demand)

Works with: Lead Developer, alongside the client's in-house engineering team

About the Company

We are a rapidly growing U.S.-based, AI-native product studio. We take companies from idea to launch-ready software in weeks, then partner with them through fast, two-week sprints to build and scale production systems. We have shipped 200+ products and hold a high bar on engineering quality even as we move quickly. Our team is fully distributed, and every engineer owns meaningful, visible work.

About the Role

We are building workflow-heavy business software for one of our clients, inside an existing production codebase shared with the client's own engineering team. We need a full-stack engineer who can safely extend a live system — adding tables, permissions, and workflows without breaking what is already running — and ship four to five features per two-week sprint.

This is an AI-first environment. Tools like Cursor, Claude Code, and coding agents write most of the first draft; you direct them, review every diff, and own what ships. Speed here comes from tooling and judgment, not from skipping tests, reviews, or acceptance criteria. We are looking for a genuine engineer who uses AI to go faster, not someone who leans on it in place of craft.

Key Responsibilities

Backend & Data Model

• Extend an existing production backend and data model — adding tables, permissions, and workflows without breaking live features
• Write data migrations from legacy sources, with reconciliation and duplicate review

Workflow & Business Logic

• Build server-side business rules: state machines, approval gates, independent review steps, and versioned records that keep full history
• Build a shared task engine with owners, backups, due dates, deduplication, and completion evidence

Security & Access Control

• Implement role-based access control scoped by company and assignment, enforced at both the database and the API
• Build an append-only audit log, stale-write protection, and idempotent endpoints so retries never create duplicates
• Build secure file upload and storage with versioning, malware scanning, and time-limited access links

Integrations & APIs

• Integrate email and SMS providers with templates, delivery tracking, retries, and opt-out handling
• Design and build the sync and submission APIs that the companion mobile app depends on

Web Interface & Tooling

• Build work queues, bulk assignment tools, and dashboards in the web interface

Reliability & Delivery

• Add monitoring and alerting, run access reviews and restore tests, and load test before launch
• Work through branches, code review, and feature flags alongside a second engineering team in the same repo

Required Qualifications

• 4+ years building and shipping full-stack web applications to production
• Strong relational database skills: schema design, migrations, query performance, and data integrity
• Experience with role-based access control, audit logging, and multi-tenant data isolation
• Comfort reading and extending a large codebase you did not write, adapting quickly to its stack and conventions
• Experience building workflow-heavy business software: queues, state machines, approvals, and tasks
• Experience with idempotent APIs, retries, and concurrency (stale-write protection, duplicate prevention)
• Integration experience with email and SMS providers and file storage
• Daily, hands-on use of AI coding tools (Cursor, Claude Code, or similar) on production work, with a workflow you can walk us through
• A track record of shipping fast without lowering the bar: automated tests, CI, and reviews that catch what AI gets wrong
• Strong written and spoken English — clear pull requests, precise questions, and the ability to explain tradeoffs to a client team
• Able to work core hours in U.S. time zones

Preferred Qualifications

• Experience with heavily regulated workflows
• Experience setting up agent workflows, project rules, or custom prompts that make a whole team faster with AI
• Experience migrating messy legacy data
• Experience working inside another team's codebase as an outside vendor
• Spanish (the platform is bilingual, though it is not required)

Ideal Candidate Profile

You are a strong engineer who is fast because you have mastered your tools, including AI — not because you cut corners. You are comfortable being dropped into a live codebase you did not write, and you make changes that do not break things. You think in systems: permissions, edge cases, concurrency, and what happens on a retry. You write clearly, ask precise questions, and can hold your own in front of a client's engineering team. You would rather own a problem end to end than wait for a fully specified ticket.

Why Join Us

You will build real production systems used by real businesses, ship visible work every sprint, and work inside a lean, high-caliber team that trusts your judgment. If you want to work at the frontier of AI-assisted engineering without lowering your standards, this is that seat.