Senior Product Engineer

Company Description

TestFactors is an independent company focused on helping SAP SuccessFactors clients and partners test faster, more accurately, and with greater control. The company delivers an AI-powered platform that automates testing activities and streamlines quality assurance. Its solutions provide full traceability from test to defect to retest, enabling more transparent and reliable testing cycles. TestFactors reduces testing effort and cost from initial implementation through ongoing sustainment, supporting long-term customer success.

Role Description

TestFactors is a small team building the testing platform for SAP SuccessFactors. Enterprise HR and IT teams use us to manage test cycles, generate test scripts from their configuration, and run those scripts automatically against their SuccessFactors tenants. We are hiring an engineer who owns outcomes, not tickets. You'll take a product area, learn the customer problem behind it, and carry it all the way through: design, API, UI, tests, deploy, and production. Then you'll keep it working. When something you own breaks, you find out first and you fix the whole class of problem, not just the one bug.

What You'll Do

• Own a product area end to end: talk with customers and SuccessFactors consultants, turn their problem into a clear outcome, then ship it across our Rails API and React frontend
• Improve AI test script generation, which turns customer configuration workbooks into test scripts using large language models, and prove each gain with benchmarks and grading, not opinion
• Make our browser runner (Playwright) more reliable as it drives real SuccessFactors tenants across multiple roles, test data and approval chains, and make it explain clearly why a run failed
• Deploy what you build, watch it in production, and handle incidents in your area, treating multi-tenant access control, SOC 2 and penetration testing as part of the job
• Keep the codebase healthy: AI coding agents write a large share of our code, and you'll be the judgment behind them, reviewing hard, simplifying, removing duplication, and saying no to complexity, including to the founder

What We're Looking For

• 5+ years building production web applications, including features you owned from first conversation to production support
• Deep backend experience. Ruby on Rails is strongly preferred; if your background is another framework, show us you can learn a large codebase fast
• Strong PostgreSQL: schema design, query performance, avoiding N+1 queries, safe migrations
• Comfort with React and TypeScript, enough to ship a complete feature without handing off the UI
• Daily use of AI coding tools, together with the habit of reading their output critically
• Clear writing: you can explain a trade-off in a paragraph and a production incident in a page
• You take responsibility. You close loops, you don't wait to be told, and you're comfortable pushing back

Nice to Have

• SAP SuccessFactors experience (Employee Central, Position Management, role-based permissions), from implementation, consulting or testing
• Browser automation with Playwright or a similar tool, on complex enterprise apps
• Evaluating LLM output: benchmarks, graders, prompt changes measured against a baseline
• SOC 2, multi-tenant security, or identity and SSO integrations
• Experience on a small team or as an early engineer at a startup

How We Build

• The simplest solution wins. We would rather delete code than add an abstraction
• Every feature comes with its tests: RSpec on the API, Vitest and Playwright on the frontend
• We fix root causes. One bug report is a reason to look for the same mistake everywhere
• AI agents are a core part of how we work. You're expected to use them well and to catch it when they're wrong
• We write things down. Plans, runbooks and the issue tracker are kept current, because a small, remote team depends on it

Our Stack

• API: Ruby on Rails 8 (API-only), PostgreSQL with PgBouncer, Solid Queue for background jobs, AnyCable and Redis for real-time updates, Pundit for access control
• Frontend: React 18, TypeScript, Vite, TanStack Query, Tailwind and shadcn/ui
• AI: Claude models on AWS Bedrock, pgvector for search, and our own evaluation tooling
• Infrastructure: AWS EC2, Cloudflare, Sentry

What Success Looks Like

• 30 days: you've shipped a fix or a small feature to production, and you can explain how a test script travels from workbook to automated run
• 60 days: you own one product area. You've shipped a meaningful improvement in it and closed out its open issues
• 90 days: customers and the team come to you for that area. You've cut a whole category of failures, with numbers to show it