Lead Full Stack Engineer

Stealth Startup; Stockholms län; Hybrid; SEK 800,000 - 1,100,000; Full time

Benefits offered by this job

Flexible hybrid work

Wellness allowance

Pension benefits

Professional development

Job summary

Stealth Startup in Sweden is seeking a Senior / Lead Full-Stack Developer to join a small, highly capable team and stay hands-on while guiding product and engineering practices. You will build production software on the Kotlin/Spring Boot and React/TypeScript stack, shape architecture and APIs, and lead technical discussions while advancing testing, observability and delivery in a rapidly growing company.

The role offers flexibility with a hybrid work model, modern tools, and opportunities for

Qualifications

• At least 6 years of professional software engineering experience.
• Deep experience with Kotlin/Spring Boot and React/TypeScript.
• Experience building a product or substantial codebase from the ground up.
• Strong judgement across architecture, APIs, data modelling and testing.
• A track record of raising engineering standards through technical leadership.
• Excellent English and a proactive, ownership-driven mindset.

Responsibilities

• Build production software across the Kotlin and React stack.
• Establish strong foundations for new products and services.
• Shape architecture, APIs, data models and technical standards.
• Improve testing, observability and delivery.
• Lead technical discussions and support other engineers.
• Help us make better use of AI-assisted development.

Skills

Kotlin

Spring Boot

React

TypeScript

REST APIs

MongoDB

Cloud

Kubernetes

CI/CD

Observability

AI coding tools

Tools

GitHub Copilot

Claude Code

Job description

We are building advanced technologies for mission critical scenarios and we would like you to join our team.

Our vision is to empower every first responder and frontline professional facing uncertainty.

We build technology that connects people, information and critical services enabling clearer communication, faster decisions and coordinated action when every second counts.

Now we’re looking for a Senior / Lead Full-Stack Developer to help us build what comes next.

What you’ll do

You’ll join a small, highly capable team and remain hands-on while influencing how our products and engineering practices evolve.

You will:

• Build production software across our Kotlin and React stack
• Establish strong foundations for new products and services
• Shape architecture, APIs, data models and technical standards
• Improve testing, observability and delivery
• Lead technical discussions and support other engineers
• Help us make better use of AI-assisted development

The role can be shaped around either a senior individual contributor or technical lead profile.

• Kotlin and Spring Boot
• React and TypeScript
• REST APIs and MongoDB
• Cloud infrastructure and Kubernetes
• Modern CI/CD, testing and observability
• AI coding assistants and agentic tools

Who you are

• At least 6 years of professional software-engineering experience
• Deep experience with Kotlin/Spring Boot and React/TypeScript
• Experience building a product or substantial codebase from the ground up
• Strong judgement across architecture, APIs, data modelling and testing
• A track record of raising engineering standards through technical leadership
• Excellent English and a proactive, ownership-driven mindset

You already use tools such as Claude Code, GitHub Copilot, Cursor or similar and understand how AI is changing the way software is designed, reviewed and shipped.

Experience in safety-critical or high-availability environments is a plus, as is familiarity with cloud platforms, Kubernetes and modern CI/CD.

You’ll build technology with tangible real-world impact and help shape our products during an exciting period of international growth.

We offer flexible hybrid working, modern tools, opportunities for professional development, a wellness allowance and competitive pension benefits.

Most importantly, you’ll help give the people who protect our communities technology they can trust in their most demanding moments.