Senior Full-Stack Engineer
Build modern Node.js and React applications end to end, with real influence on architecture, scalability, and quality in a high-traffic environment.
About the Company
Avaron helps you find assignments that match your skills and ambitions. As a permanently employed consultant with us, you get competitive terms – combined with the variety and growth that a consulting career offers.
About the Assignment
You will help build and evolve modern web applications end to end in an environment where scalability, reliability, and performance are central. The assignment combines frontend and backend development, with a strong focus on TypeScript, robust APIs, and solutions tailored for both web and mobile clients.
You will work close to engineering, product, and business stakeholders, contributing to software that needs to perform well in production at scale. Clean architecture, observability, automated quality assurance, and secure delivery are important parts of how the work is done. This is a strong opportunity for you if you enjoy hands-on development while influencing technical decisions in a high-traffic environment.
Job Description
- You will build and maintain modern full-stack applications using Node.js, React, and TypeScript.
- You will design and develop APIs and orchestration layers that support web and mobile clients.
- You will contribute to system design decisions around caching, scalability, reliability, performance optimization, and observability.
- You will help ensure high software quality through unit testing, automated quality assurance, and maintainable test coverage.
- You will drive engineering best practices around clean code, code reviews, CI/CD, security, and maintainability.
- You will collaborate closely with engineering, product, and business teams to move work forward effectively.
- You will work in an Agile setup with sprint planning, estimation, iterative delivery, and continuous improvement.
Requirements
- Strong full-stack engineering experience with deep expertise in Node.js and React.
- Proficiency in TypeScript and hands-on experience building scalable, maintainable, and strongly typed codebases.
- Strong understanding of system design principles, including caching strategies, scalability, reliability, performance optimization, and observability.
- Proven experience building and operating large-scale, high-traffic applications in production environments.
- Hands-on experience with modern Node.js frameworks.
- Strong expertise in unit testing and automated quality assurance using Vitest or Jest.
- Strong knowledge of software engineering best practices, including clean code, testing, code reviews, CI/CD, security, and maintainability.
- Ability to collaborate effectively across engineering, product, and business teams.
- Practical experience working in Agile environments.
Nice to have
- Experience designing Backend-for-Frontend (BFF) architecture.
- Experience creating APIs and orchestration layers tailored for web and mobile clients.
- Previous experience with Fastify.
What We Offer
- Permanent employment at Avaron AB
- Occupational pension
- Wellness allowance of SEK 5,000 per year
Application
Selections are made on an ongoing basis – apply as soon as you can.
- Platser
- Stockholm
- Distansarbete
- Hybridarbete
Stockholm
Om Avaron AB
Avaron förser företag i hela Sverige med tekniska konsulter och specialister. Vi fokuserar på IT, mjukvaruutveckling, teknik, projektledning och andra tekniska domäner. Grundat 2018 av en mjukvaruingenjör som tröttnade på bemanningsföretag som inte förstod rollerna de rekryterade till.