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Long Description
We're looking for a Senior Software Engineer to join one of our Content Management System (CMS) product teams in the UK, working on a key part of the Optimizely platform.
Our CMS is one of the core products in the Optimizely ecosystem. It enables businesses to create, manage, and publish digital content—such as websites, landing pages, and product experiences—across multiple channels. It works alongside other parts of the platform, including experimentation, campaign management, and data services, to support end-to-end digital experience creation and optimization.
We offer both PaaS and SaaS versions of our CMS and are continuously evolving it to be more scalable, composable, and developer-friendly. As part of this team, you'll help build and evolve core CMS capabilities while contributing to the long-term direction of the platform.
Introduction
Job Responsibilities
- Design, build, and maintain scalable, maintainable software systems
- Develop CMS features, add-ons, APIs, and integrations with external systems
- Contribute to system design and architectural decisions
- Ensure product quality through automated testing and operational best practices
- Own services in production, including monitoring and incident handling
- Collaborate with product managers, designers, and engineers to deliver features end-to-end
- Consider real-world usage and customer needs in technical decisions
- Mentor other engineers and contribute to knowledge sharing
- Participate in hiring and help grow the engineering team
Knowledge and Experience
Must have
- ~8+ years of experience in software engineering (flexible depending on experience)
- Strong fundamentals in software design and engineering
- Experience with C# and .NET, and React on the frontend
- Experience with CMS platforms, content modelling, or similar domains
- Experience building and operating cloud-based systems
- Comfortable using AI tools (e.g., Claude or similar) in your daily workflow for problem solving, learning, and improving code quality and delivery speed; able to guide AI-assisted development using structured instructions (e.g., well-defined prompts or Markdown-based instruction files) to generate code in a controlled and maintainable way, with interest or experience in leveraging AI agents to further enhance productivity
- Strong testing mindset, with a focus on building reliable, well-tested systems and maintaining high code quality
- Comfortable working in cross-functional, agile teams
- Strong communication and collaboration skills
Nice to have
- Experience with Optimizely CMS or similar CMS/DXP platforms
- .NET Core / MVC
- SQL (especially MS SQL)
- REST APIs or GraphQL
- Containers and cloud platforms (e.g., Azure)
- Experience building modular systems with continuous delivery
- Experience building AI-powered features (e.g., RAG systems, LLM integrations)
- Degree in Computer Science or equivalent experience
Education
Bachelor’s Degree (Computer Science or engineering preferred) or equivalent work experience
Optimizely is committed to a diverse and inclusive workplace. Optimizely is an equal opportunity employer and does not discriminate on the basis of race, national origin, gender, gender identity, sexual orientation, protected veteran status, disability, age, or other legally protected status.
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