Senior Full-Stack Engineer (Backend-Focused) (f/m/x)

Are you a versatile developer ready to build something extraordinary? Join us as our software engineer and spearhead the creation of a cutting-edge platform.

Pactos is a venture-backed B2B SaaS start-up based in Munich. We’re revolutionizing the external workforce management with an AI-powered operating system. Used by leading corporates, Pactos help streamline the source-to-pay process with staffing providers in a compliant, scalable, and transparent way. Thus, our customers excel in operation efficiency and re-gain full workforce visibility.

Tasks

• Architect our Application: Design and build modern web applications using TypeScript and NestJS , with a strong focus on scalable backend systems, complex domain modeling, and multi-tenant SaaS architecture.
• End-to-End Ownership: Take full ownership of features from requirements through implementation, testing, and ensuring reliable operation in production.
• Cross-Functional Collaboration: Work closely with product, design, and engineering to continuously evolve a multi-tenant SaaS platform.
• System Optimization & Scaling: Drive best practices for performance, scalability, and maintainability in a growing system.
• Technical Excellence & Mentorship: Contribute to architectural decisions, conduct code reviews, and mentor engineers to foster a high-quality engineering culture.

Requirements

• 3+ years of professional experience in full-stack / backend development
• Demonstrated ability to build scalable, high-performance web applications and implement effective optimization strategies
• Proficiency in modern backend frameworks (e.g., NestJS) and the integration of RESTful APIs, as well as familiarity with relational and non-relational databases (e.g., PostgreSQL)
• Strong advocate for AI and experienced with coding tools (e.g., Claude Code, Codex)
• Excellent analytical and troubleshooting abilities with a passion for clean, maintainable code, as well as experience in agile development methodologies
• Strong interpersonal skills with a proven track record of cross-functional collaboration and glue work
• Highly motivated and proactive, eager to take ownership of the full domain and follow through in a fast-paced, aspiring startup environment
• Fluency in English

Benefits

• Attractive comp + ESOP: Competitive salary plus meaningful equity
• True Ownership: You’ll be among the first, well-experienced developers. Everything is yours to shape. Define our product from day one.
• Speed: We make decisions in hours, not weeks. No politics. No BS.
• Colleagues you’ll want to work with: Pragmatic, product-obsessed, and committed to winning - we're a tight-knit, ambitious team with a builder mindset
• Modern stack, flexible setup: on-site in Munich, outcome-driven, and lots of fun (e.g., Oktoberfest)

Tell us why this role is exciting for you and link some work references you're proud of. Let’s build something bold!