Senior Full-Stack Developer (React / Node.js) (m/f/x)

Senior Full-Stack Developer (NodeJS/Typescript)

Department: Business Partner Transparency

Employment Type: Permanent - Full Time

Location: Madrid

Description

As a Senior Full-Stack Developer, you’ll play a key role in shaping the future of Business Partner Transparency (BPT) within our osapiens HUB. This enterprise‑grade platform helps companies comply with critical ESG regulations like:

• The German Supply Chain Due Diligence Act (LkSG) – ensuring suppliers uphold human rights and environmental standards.
• The Whistleblower Directive – providing secure, anonymous reporting channels.
• The Corporate Sustainability Due Diligence Directive (CSDDD) – upcoming EU‑wide sustainability compliance.

Our osapiens HUB is a modern, enterprise‑grade development platform that enables businesses to build powerful applications without worrying about infrastructure, scaling, or failover. You’ll help develop and refine this cutting‑edge, serverless ecosystem while delivering meaningful solutions for international clients.

This role is based in Madrid, where you'll collaborate with a talented, forward‑thinking team. We embrace a hybrid work model, with three days a week in the office, ensuring the perfect balance between in‑person collaboration and remote flexibility.

Key Responsibilities

• Design, build, and optimize full‑stack features using modern back‑end technologies, ensuring scalability and maintainability.
  Front End experience is good to have.
• Develop and enhance innovative software solutions that automate complex compliance workflows for businesses of all sizes.
• Collaborate closely with product managers, designers, and engineers in small, agile squads (5-7 people) to define, refine, and implement features.
• Ensure high‑quality, secure, and efficient code through rigorous reviews, automated testing, and continuous integration/deployment (CI/CD) practices.
• Own the architecture and design of JavaScript‑based solutions, optimizing for performance, reliability, and user experience.
• Contribute to technical strategy and decision‑making, identifying opportunities for innovation and process improvements.
• Mentor and support junior developers, fostering a culture of learning and technical excellence within the team.

Skills, Knowledge and Expertise

• Strong experience in full‑stack development with a focus on Backend (Node:JS and TypeScript) React.JS is desirable.
• Expertise in web services development and integration (REST, GraphQL, etc.).
• Familiarity with Git for version control and collaboration.
• Strong product mindset – you think beyond code, considering user experience, business impact, and scalability.
• Agile experience – comfortable working in sprints, participating in stand‑ups, and iterating quickly.
• Excellent communication skills in English (C1). Spanish is a bonus but not necessary.

Benefits

• A purpose‑driven mission with and for global industry pioneers in tackling complex challenges.
• Room for creativity through collaborative teamwork and an open communication culture.
• Flexibility and team bonding with our hybrid work options.
• Fuel for your growth journey, both personally and professionally.
• Sustainable mobility options, promoting eco‑friendly commuting solutions.
• Fun team events and outings with our global teams.
• Inspiring workspaces in Madrid and beyond.
• 25 days of vacation.
• Health Care Insurance.
• Other perks.