Operating(Senior) Fullstack Engineer (React, TypeScript, Node.js)

Operating (https://www.operating.app) is looking for a (Senior) Fullstack Engineer to help build the modern operating system for consultancies and take ownership of product feature development. You’ll join a small, autonomous engineering team where the core stack is React, TypeScript, Node.js, Postgres, and AWS.

Your role with us

As a Fullstack Engineer, you’ll take end-to-end ownership of meaningful product features in our SaaS platform. You’ll work across the full stack, close to customers and business problems. The focus areas of the role can be adjusted based on your experience and strengths, while the core responsibility remains building high-quality, pragmatic solutions that scale as the product and customer base grow. You’ll work closely with our CTO Mikko Karjalainen and senior engineers, pair when needed, and help shape the future architecture of the platform.

What you’ll do:

• Design and build new product features end-to-end in TypeScript, React, Node, and Postgres
• Own and improve specific domains of the application over time
• Collaborate with product & design to define solutions
• Contribute to our growing engineering standards and processes
• Review Pull Requests, mentor teammates, and raise the bar on quality
• Help scale the platform as customer usage grows: performance, reliability, platform systems

What makes you thrive in this role

You’re pragmatic and product-minded, focusing on outcomes rather than tickets. You’re comfortable with ambiguity and making sensible decisions with imperfect information. You care deeply about user experience and customer impact, and you actively bring your ideas into the team, challenge assumptions when needed, and contribute with a kind, collaborative mindset while taking true ownership of your work.

You are expected to have:

• At least 3 years of full stack experience (startup or SaaS environment strongly preferred)
• Strong experience with React, TypeScript, and Node.js
• Ability to independently drive features from idea to production
• A full working proficiency in English for day-to-day collaboration (Finnish skills are preferred)

Bonus points if you have experience with:

• Multi-tenant SaaS architectures
• Billing, finance, resource planning, or workflow automation software
• Working in a startup or scale-up environment where roles and priorities evolve
• AI, data engineering, integrations, DevOps, or platform engineering (AWS, CI/CD)

Why you’ll love it here

• You’ll have real ownership — your ideas will directly shape the product
• You’ll work on a broad set of product areas, not a tiny slice of a giant system
• Low-hierarchy, high-trust culture
• Opportunity to grow into domain leadership or tech lead roles
• We’re a kind, pragmatic, no-drama team
• Customers love the product — and we talk to them often

Practicalities:

This is a full-time and permanent position with a preferred start date as soon as possible, and you will be employed directly by Operating Solutions Oy. The role is based in Maria01 in Helsinki with a primary focus on working from the office while allowing flexibility for remote work when it makes sense. Salary in this position is approximately 4000–5000 €/month depending on your experience. In addition, you’ll be offered an employee option program, comprehensive occupational healthcare, and everyday benefits including a paid moving day, gym, and sauna access

Interested?

Please submit your CV and motivation letter in PDF-format in English by the latest 11th of January 2026 via our application system. Remember to use the system as we do not accept applications by email. We want to ensure that all applicants can participate in the process equally, and we will take individual accessibility needs into account where necessary.

Learn about Operating here and the team members here. For more information about the position and recruitment process, please contact aTalent’s Senior Recruitment Consultant Kati Hautakoski [+358 50 552 0419, kati.hautakoski(at)atalent.fi] during 19.-22.12.2025 and 7.-9.1.2026. If I’m unable to answer your call right away, please leave a text message and I’ll get back to you as soon as possible.