CodeNext - Staff Software Engineer (f/m/d)
SonarSource
Software Engineering
bochum, germany
Posted on Feb 20, 2026
Who is Sonar?
Sonar helps prevent code quality and code security issues from reaching production, amplifies developers' productivity in concert with AI assistants, and improves the developer experience with streamlined workflows. Sonar analyzes all code, regardless of who writes it — your internal team, genAI, or third parties — resulting in more secure, reliable, and maintainable applications. Rooted in the open source community, Sonar’s solutions support over 30 programming languages, frameworks, and infrastructure technologies. Today, Sonar is used by +7M developers and 400K organizations worldwide, including the DoD, Microsoft, NASA, MasterCard, Siemens, and T-Mobile.
We believe in developing great products that are supported by great internal teams and a strong culture. We are highly committed to and obsessed with the company, users, each other, and our open source community. We have high standards and hold each other accountable for acting with positivity, dedication, thoughtfulness, empathy, and passion daily.
We are deliberate with our decisions with high clarity of intention. At the same time, we feel extreme urgency and move forward quickly.
And lastly, we are highly effective and operationally efficient. We operate collectively as One Team to accomplish our goals.
At Sonar, CODE is more than just an acronym – it's a mindset that defines daily operations.
Why You Should Apply:
At Sonar, we’re a group of brilliant, motivated, and driven professionals working hard to help supercharge developers to build better, faster. Sonar helps to continuously improve code quality and code security while reducing developer toil. This means that developers can focus on doing more of what they love and less of what they don’t. Our solutions don’t just solve symptoms of problems – we help fix issues at the source – for all code, whether it's developer-written, AI-generated, or from third parties.
We have a dynamic culture with employees worldwide and hub offices in the USA, Switzerland, the UK, Singapore, and Germany. Team members should be able to come to work every day, work on a product they are proud of, love what they do, and feel energized by their peers. With our roots deep in the open source community, we’re all about the mission: supercharge developers to build better, faster.
The Impact You Will Have:
The Sonar Code Next team is looking for a visionary Staff Software Engineer to join a fast-paced, dynamic group at the intersection of Large Language Models (LLMs), static analysis, and programming languages. As a technical leader in this team, you’ll directly influence AI-driven solutions by designing and scaling the tools and infrastructure that make these initiatives possible. In this hands-on, high-impact role, you’ll focus on architecting methodologies that enhance code quality—ensuring that all solutions are scalable, maintainable, and ready for global production. Working on cutting-edge, AI-driven projects, you’ll architect and steer the boundaries of automated code quality and security.
Our mission is to harness our expertise in static analysis and LLMs to advance AI’s ability to understand, generate, and improve code. We develop prototypes grounded in cutting-edge research, testing innovations across the LLM development lifecycle—from data processing and model training to benchmarking. Our approach leverages techniques such as supervised fine-tuning (SFT), direct preference optimization (DPO), reinforcement learning from human feedback (RLHF), and retrieval-augmented generation (RAG) to enhance model performance and code quality.
What You Will Do Daily:
- Architect and oversee the tooling and infrastructure to support AI-driven solutions for code quality and security across diverse language ecosystems.
- Lead the design and optimization of AI-focused experiments, creating robust systems to evaluate modern techniques, including fine-tuning, RAG, DPO, and RLHF.
- Write scalable, production-quality code mainly in Python, and sometimes in Java, TypeScript, or Rust, to support AI workflows, dataset processing, and evaluation frameworks.
- Design and maintain high-throughput benchmarking pipelines to assess LLM performance in generating clean, maintainable code.
- Process and refine complex datasets, ensuring they’re structured and optimized for training and evaluation.
- Define the integration strategy between AI systems and static analysis tools, enabling AI-assisted insights for developers.
- Collaborate with static analysis experts and AI researchers to translate experimental research into scalable, working software architectures.
- Ensure the scalability, reliability, and maintainability of AI tooling as it transitions from research-driven experimentation to enterprise production.
The Experience You Will Need:
- Proven mastery of software engineering with deep proficiency in Python as well as experience in other languages such as Java, C++, Rust, or JS/TS.
- Advanced software architecture foundation, including distributed systems, complex algorithms, enterprise CI/CD, and best practices for building global-scale software.
- Deep curiosity about LLMs, static analysis, and the nuances of multiple programming languages, recognizing their specific strengths and challenges.
- Genuine interest in AI-driven software development and a proven ability to lead projects integrating AI with developer tools.
- Pragmatic approach to problem-solving, balancing high-level technical strategy with the hands-on building of production-ready systems.
- Self-driven mindset with the technical authority to challenge the status quo, yet remain humble and open to learning and feedback.
- Bonus points for hands-on experience with LLM-related projects, static analysis, or deep expertise in compiler theory.
- Leadership and Ownership: You can take a complex vision from concept to completion, guiding others through technical uncertainty.
Why You Will Love It Here:
- Our culture and mission set us apart. We have a dynamic work culture that values respect and kindness and embraces the right to fail (and get right back up again!).
- Great people make a great company. We value people skills as much as technical skills and strive to keep things friendly while still being passionate leaders in our domains.
- We have a flexible work policy that includes 3 days in-office and 2 days work-from-home each week for those located near our office locations; some locations such as Dubai, India, Japan and Australia operate fully remotely.
- We have a growth mindset. We love learning and believe continuous education is critical to our success. In an ever-changing industry, new skills are necessary, and we're happy to help our team acquire them.
- As the leader in our field, our products and services are as strong as our internal team members.
- We embrace transparency with regular meetings, cascading messages and updates on the growth and success of our organization.
Benefits of Working With Sonar:
- Pension Scheme: 1st Pillar (Unterstützungskasse): Automatic, financed by Sonar, 3% of gross salary, an additional benefit in addition to your salary.
- Pension Scheme:2nd Pillar (bAV): Voluntary, 15% contribution by Sonar from social security savings.
- We encourage usage of our robust time-off allocations with 28 PTO days for our employees based out of the Geneva region, plus additional days based on seniority and circumstances.
- Sonar recognizes holidays on working calendar days. If the holiday date occurs on a Saturday, we will recognize the day on the preceding Friday. If the holiday date occurs on a Sunday, we will recognize the day on the following Monday.
- Public transport reimbursement of 60% for annual subscription.
- Global workforce with employees in 20+ countries representing 35+ unique nationalities.
- We have an annual kick-off somewhere in the world where we meet to build relationships and goals for the company.
We Value Diversity, Equity, and Inclusion:
At Sonar, we believe that our diversity is our strength. We are a global company that values and respects different backgrounds, perspectives, and cultures.
We are committed to fostering a diverse and inclusive work environment where everyone feels valued and empowered to contribute their best. We are proud to be an equal opportunity employer and welcome all qualified applicants, regardless of race, color, religion, gender, gender identity or expression, sexual orientation, national origin, genetics, disability, age, or veteran status.
All offers of employment at Sonar are contingent upon the precise results of a comprehensive background check and reference verification conducted before the start date.
Applications that are submitted through agencies or third party recruiters will not be considered.