Senior Software Engineer

Job Description

At WithSecure™, we protect businesses all over the world. Our SaaS solutions safeguard against modern cyber threats, and our innovative Co-security approach reflects our belief that true protection requires collaboration and shared expertise. No one can solve every cyber security problem alone. Our vision is to become Europe’s flagship in cyber security. Every day, our talented teams work to prevent cyber extortion, secure critical infrastructure, and prevent misuse of sensitive data. At WithSecure, it’s our people who make us exceptional – a diverse community that values passion, purpose, and a commitment to workplace well-being. If you’re ready to make an impact with a company that’s transforming cybersecurity, we’d love to hear from you.

About the role

We are looking for a Senior Software Engineer to join a small, experienced team that builds and operates the web applications and backend services behind our detection and response offering.

The team owns customer-facing security applications, internal tools used daily by our analysts, and the services and reporting pipelines that support them.

This is a hands-on engineering role. You will design, build, and operate production features across the front end and backend, take ownership of the components you work on, and help shape how the team delivers. You will work closely with product management, security analysts, and other engineering teams.

Our front-end applications are built with Vue 3. Our backend technology stack includes Python and Node.js/TypeScript across applications, serverless functions, and reporting pipelines, as well as Rust in several services.

Some parts of the product are mature and evolve carefully, while others are new and still being shaped. We are also actively decommissioning selected legacy components.

AI is an important part of both our products and our engineering practices. We build agents on AWS Bedrock with retrieval over our own documentation, automate the analysis of production alerts and CI failures, and provide AI assistant capabilities to users through our applications.

We also use AI coding assistants in our daily development work across production codebases, with agent instructions maintained in every repository. We expect you to use these tools thoughtfully and to share what works with the rest of the team.

Technical responsibilities

• Design, build, and maintain Vue 3 front-end applications, including shared components, state management, and integrations with GraphQL and REST APIs.

• Build and operate backend services, serverless functions, and reporting pipelines in Python and Node.js/TypeScript.

• Contribute to services written in Rust.

• Contribute to our AI capabilities, including agents, retrieval over internal documentation, and user-facing AI features.

• Work with AWS services, including Lambda, containers, API Gateway, DynamoDB, S3, Step Functions, RDS/PostgreSQL, OpenSearch, Bedrock, and related operational tooling.

• Contribute to infrastructure as code across a mixed toolchain.

• Support the ongoing modernisation of our CI/CD environment, including the migration of build and deployment pipelines from Jenkins to GitHub Actions.

• Take an active part in code review and help maintain a high standard of quality across the codebase.

• Contribute to architecture and design decisions, and own the technical design of the components you build.

• Document your technical decisions clearly so the team can understand and build on them.

• Participate in incident handling and operational support for the services owned by the team, and help improve the tooling that makes this easier.

Team responsibilities

• Participate in sprint and quarterly planning, and help estimate and break down epics into well-defined tickets.

• Take ownership of features from refinement through delivery and operation.

• Raise dependencies and blockers early and work with other teams to resolve them.

• Contribute to the team’s ways of working, including review conventions, ticket standards, and documentation.

• Support colleagues through code review, pairing, and knowledge sharing, and help onboard new team members.

• Help the team use AI coding assistants effectively, including maintaining agent instructions in the repositories you work in.

Qualifications

• Several years of commercial software development experience, including building and operating production services.

• Strong experience building modern front-end applications, preferably with Vue 3.

• Confidence working with JavaScript-based front-end applications. Our Vue codebases use JavaScript rather than TypeScript.

• Solid backend development experience with Python or Node.js/TypeScript, and a willingness to work in both.

• Experience with Rust is an advantage, but a genuine willingness to learn is sufficient.

• Experience working in an agile team, including refining and estimating work in Jira or a similar tool.

• Experience using AI coding assistants in real codebases, with the judgement to review and correct their output.

• Practical AWS experience and an understanding of service-oriented or serverless architectures in production.

• Experience with infrastructure as code (we mainly use Terraform, with some AWS CDK and CloudFormation) and CI/CD pipelines such as GitHub Actions.

• Good written and spoken English.

Nice to have

• Experience building LLM-backed features or agents, such as tool calling, retrieval pipelines, or evaluation.

• Experience migrating CI/CD pipelines (for example from Jenkins to GitHub Actions) or decommissioning legacy components.

• Experience with GraphQL clients and schemas in front-end applications.

• Experience with observability and operations, including metrics, structured logging, alerting, and debugging production issues in AWS.

• Familiarity with Svelte or SvelteKit. We maintain one TypeScript-based SvelteKit application that is being decommissioned, so you may work with it during the transition. New front-end development is focused on Vue 3.

• A background in cyber security or experience building tools for security analysts and incident responders.

Key competencies

• Takes ownership of their work end to end, from design through to running it in production.

• Balances delivering the next increment with keeping the codebase healthy.

• Identifies friction and helps remove its underlying cause.

• Communicates clearly, particularly in writing, and provides enough context for others to act.

• Approaches AI with curiosity and discipline, experiments thoughtfully, communicates honestly about what does not work, and applies appropriate care before changes reach production.

• Shares knowledge through demonstrations, documentation, reviews, pairing, and day-to-day collaboration.

• Works effectively with ambiguity and is comfortable in an environment that combines mature systems with newer technologies.