Senior Software Engineer – Security Libraries

Responsibilities

Our client, a leading observability and security platform provider, is seeking a Senior Software Engineer to join their Security Libraries team. We are representing this confidential organization in their search for a polyglot engineer who will contribute across multiple security libraries with expertise in.NET or Java.

In this role, you will:

• Design, build, and own security integrations and detections (WAF, RASP/exploit prevention, API Security, IAST, SCA) across multiple libraries, with .NET and/or Java as your primary focus
• Take projects from prototype to deployed, correct, operable, and maintainable solutions, writing code that safely instruments thousands of applications in production
• Own your systems operationally: monitor production telemetry, debug challenging cross-system issues, and drive down customer-facing problems
• Shape the roadmap by helping define OKRs for the systems you own, breaking features into components other engineers can build in parallel, and driving designs to alignment across security library teams
• Partner with product management, backend, and frontend teams to turn product ideas into capabilities customers actually adopt
• Mentor teammates and act as a force multiplier by raising the bar on code quality and testing
• Represent the organization in relevant language and security communities

What We're Looking For

Required qualifications:

• Expert-level proficiency in at least one of .NET (C#) or Java, with polyglot capabilities to contribute idiomatically across other libraries when needed
• Strong software-engineering fundamentals: consistently ship modular, maintainable code with little guidance
• Product-engineering mindset: care about user experience and product outcomes as much as the code itself
• Experience building and shipping libraries or SDKs consumed by other developers, with understanding of packaging, versioning, and backward compatibility
• Deep care about performance and cost optimization, with experience measuring and improving both
• Operational maturity: take full accountability for what you ship in production
• Clear communication skills in writing and in person, with ability to drive alignment through RFCs and informal collaboration
• BS/MS/PhD in a STEM field or equivalent experience

Bonus qualifications:

• Deep expertise in.NET or Java, including language runtime internals and instrumentation (JVM, bytecode instrumentation, CLR/JIT/GC, IL rewriting)
• Track record of shipping across multiple languages (Go, Node.js, Python, Ruby, PHP, C/C++)
• Application security background: WAF, RASP, SAST/IAST/SCA, threat detection, or secure-by-design practices
• Experience with auto-instrumentation, APM/distributed tracing, or code telemetry and introspection
• History of maintaining open-source projects with public packages (NuGet, Maven)
• Experience with AI-assisted developer tooling or agentic workflows
• Developer-experience or customer-support sensibility

How We Work with You

When you apply through Get A Job.ai, our talent team will review your profile and conduct an initial screening to understand your background and expertise. If there's a strong match, we will submit your candidacy to our client for consideration. Throughout the process, we act as your advocate and partner.

Please apply exclusively through Get A Job.ai and do not contact the client directly, as all applications must be coordinated through our recruiting team to ensure proper consideration.

This is a hybrid position based in Bordeaux, Lyon, Nantes, Paris, or Sophia Antipolis, France.

Pay

Compensation details will be discussed during the screening process and are competitive with senior engineering roles in the observability and security space.

Equal Opportunity: Get A Job.ai is committed to equal employment opportunity. We consider all qualified applicants without regard to race, color, religion, sex, national origin, age, disability, veteran status, or other legally protected characteristics.