Senior Optimizely Developer – (C#/.NET, CMS, Web Experimentation) - 100% Remote - W2 Contract

Senior Optimizely Developer – (C#/.NET, CMS, Web Experimentation) - 100% Remote - W2 Contract Optomi, in partnership with a global leader in infrastructure engineering software and digital solutions, is seeking a Senior Optimizely Developer to fulfill a contract position with a client based in Exton, PA.

The ideal candidate will be a senior full-stack engineer with deep expertise across both Optimizely CMS and Optimizely Web Experimentation.

This individual will serve as a technical expert within a rapidly evolving Digital Marketing organization, building scalable CMS architecture while also developing sophisticated A/B tests, personalized web experiences, and frontend experimentation.

This is an opportunity for someone who enjoys working at the intersection of engineering, marketing, product, UX, and conversion optimization while leveraging AI-assisted development tools to accelerate delivery. What the Right Professional Will Enjoy!

The opportunity to serve as a technical expert for Optimizely within a major digital transformation, helping shape how a global organization builds and delivers its digital experiences.

The opportunity to work across both backend CMS engineering and frontend experimentation rather than being limited to traditional CMS development.

The opportunity to build sophisticated A/B tests, personalization campaigns, reusable web components, and integrations that directly impact the digital customer experience.

The opportunity to work within a forward-thinking engineering culture that encourages the use of AI-assisted development tools such as GitHub Copilot and ChatGPT to accelerate development, testing, and experimentation.

Apply Today If Your Background Includes: 5+ years of full-stack web development experience with 3+ years of hands-on development within the Optimizely/Episerver ecosystem.

Deep experience developing and supporting Optimizely CMS, including reusable blocks, page templates, content models, and scalable CMS architecture. Strong backend development experience with C#, .NET Core, and MVC.

Hands-on experience with Optimizely Web Experimentation, including developing and deploying complex A/B, split, and multivariate tests. Advanced frontend development experience with JavaScript/ES6+, HTML5, CSS3/SASS, and modern frontend technologies such as React, Vue, or jQuery.

Strong experience with DOM manipulation and dynamic content rendering for sophisticated experimentation use cases. Understanding of Optimizely-specific concepts including Project JS, visual tags, audience targeting, anti-flicker techniques, and caching behaviors.

Experience building personalized digital experiences based on audience segments, customer attributes, or account-based marketing strategies.

Experience developing APIs and integrations between Optimizely and enterprise platforms such as Salesforce, Marketo, Adobe Commerce, or similar systems. Experience optimizing enterprise websites for performance, scalability, security, and Core Web Vitals.

Experience with Git and modern CI/CD pipelines, including Azure DevOps, GitHub Actions, or similar technologies. Experience performing cross-browser and cross-device testing and troubleshooting issues such as layout shifts, flicker, and inconsistent experiment behavior.

Experience working closely with Product, CRO, Marketing, and UX/UI teams to translate business ideas and Figma designs into production-ready digital experiences. Experience establishing development standards, technical best practices, and governance for enterprise web platforms.

Demonstrated interest in leveraging AI-assisted development tools to accelerate coding, debugging, testing, and delivery. Experience with Optimizely Feature Experimentation/Full Stack, server-side testing, or feature flagging is a plus.

Experience supporting complex enterprise B2B websites, lead-generation funnels, and gated content experiences is preferred. Active Optimizely CMS or Web Experimentation certifications are a plus.