Experienced Software Engineer – Java/.NET Platform

COMSOL, Inc.; Stockholms kommun; On-site; SEK 650,000 - 900,000; Full time

Benefits offered by this job

A competitive salary

Individual pension plans

Sponsored gym membership

Work-life balance with regular working

Job summary

COMSOL, Inc. in Stockholm seeks an experienced software engineer to help build the platform foundations behind COMSOL Multiphysics.

You will work on runtimes, libraries, build systems, and platform integrations in Java and C#, with automation tooling as a core part of the role. You will contribute to cross‑platform development across Windows, Linux, and macOS, explore API improvements, and help evolve build and development infrastructure.

Qualifications

• M.Sc. or equivalent degree in computer science, engineering, mathematics, or physics.
• Excellent programming skills with proficiency in at least one object-oriented programming language.
• Several years of professional software development experience.

Responsibilities

• Write and review code across the COMSOL platform stack.
• Investigate platform and compatibility issues and contribute to technical specs and design.
• Develop and maintain build and platform infrastructure, and automation tooling.
• Test changes across Windows, Linux and macOS and ensure cross-platform reliability.
• Contribute to the long-term technical direction of the platform team.

Skills

Java

C#

Object-oriented programming

Education

M.Sc. in computer science, engineering, mathematics, or physics

Tools

Build systems

Dependency management

Software packaging

Job description

We are looking for an experienced software engineer to join the team responsible for developing the software platforms underlying COMSOL Multiphysics®. You will work with the runtimes, libraries, build systems, and platform integrations that form the foundation of a large, cross-platform engineering software product. The majority of the development is done in Java and C#, together with build and automation tooling. About COMSOLCOMSOL develops cutting-edge mathematical modeling software that powers innovations in physics and engineering. Our flagship product, COMSOL Multiphysics®, is widely used across all fields of engineering, manufacturing, and scientific research to model multiphysics systems. Our customers leverage our software to understand, predict, and optimize product designs and processes. Founded in Sweden in 1986, COMSOL has expanded globally with 16 offices employing more than 500 people worldwide. RoleBased in our newly renovated office in central Stockholm, you will join the core group developing the user interface, communication, and data layer functionality of the COMSOL product suite. The group is also responsible for the Application Builder, Model Manager, COMSOL Server, and COMSOL Compiler functionality, which customers use to create, manage, deploy, and run simulation models and apps. In this role, you will work on several of the software platforms on which our products are built. This includes the Java and .NET runtimes and their ecosystems, third-party libraries, database connectivity and persistence technologies, application launchers, build systems, and integration of vendored software. The work spans multiple operating systems and a large codebase with a long development history. You will evaluate and integrate new runtime and library versions, investigate compatibility issues, implement or backport APIs and other changes where needed, and develop automation that makes recurring platform and dependency work more efficient and reliable. The role also provides opportunities to evolve the platforms themselves. Depending on your experience and interests, this can include introducing new platform capabilities and APIs, improving how runtimes and third-party components are integrated, evolving build and development infrastructure, and finding better ways to support development across the product organization. You will have room to identify improvements and contribute to the longer-term technical direction of the areas you work with. Responsibilities include writing and reviewing code, investigating platform and compatibility issues, contributing to technical specifications and design, developing build and platform infrastructure, and testing changes across the supported product platforms.

Qualifications

• M.Sc. or equivalent degree in computer science, engineering, mathematics, or physics.
• Excellent programming skills with proficiency in at least one object-oriented programming language.
• Several years of professional software development experience.
• An interest in working with complex software systems and improving the technical foundations on which other development depends.

Experience with the following will be highly valued:

• Large software projects and mature codebases.
• Java and/or .NET runtime environments and their library ecosystems.
• Build systems, dependency management, and software packaging.
• Cross-platform development on Windows, Linux, and macOS.
• Integrating or adapting third‑party and open-source software.
• Build and development automation.
• Designing or evolving software platforms, frameworks, or developer infrastructure.

We also offer:

• A competitive salary
• Individual pension plans
• Sponsored gym membership
• Work-life balance with regular working hours

To ensure a smooth onboarding process, onsite presence is required. Once onboarded, hybrid work options are available.

No background in physics or simulation is required. At COMSOL, you will be part of a company where software developers, mathematicians, physicists, and engineers work together to develop software for science and engineering.Working at COMSOLAt COMSOL, platform engineering is closely connected to product development. You will work on technical foundations used throughout the COMSOL product suite, with opportunities both to ensure that those foundations remain robust and current and to improve how they support future product development. Decisions about runtimes, libraries, build systems, and operating-system support have a direct impact on a complex engineering product with a long lifetime.New team members quickly become essential contributors to ongoing development projects. As the company continues to expand, there are plenty of opportunities for employees to advance in their roles and become leading experts in their areas of focus. This journey will be accompanied by experienced colleagues and a collaborative working environment.