Senior Web Developer with Sitecore Experience

HLK, a full-service digital agency with offices in St. Louis and Chicago, is looking for a Senior Web Developer with Sitecore experience to join our growing Technology Group. At HLK, Senior Developers use a variety of technologies and APIs to build robust systems for sharing information and serving customer-centric web experiences to users worldwide.

This role will play a key part in client platform migrations while also continuing to design, build, and optimize digital solutions that support long-term client needs. The successful candidate should possess significant experience in Sitecore 9.x and ideally exposure to Sitecore XM Cloud and the modern composable ecosystem. A Sitecore Professional Developer Certification is a big plus.

The successful candidate must have an insatiable desire to learn, explore and implement technology solutions for our clients while aligning with the agency’s core values: Be Curious, Be Thoughtful, and Be Brave.

• Significant experience developing data-driven web applications.
• Expert-level grasp of .NET (Framework and .NET Core) and MVC architecture.
• Strong front-end skills (Semantic HTML5, CSS, JavaScript, and associated frameworks and tooling).
• Ability to utilize new development technologies to find creative solutions for websites and web applications.
• Ability to assess, use, and create REST and GraphQL APIs.
• Strong knowledge of Sitecore development, customization, and integration, including experience with Sitecore 9.x and an understanding of XM Cloud, Sitecore Headless Services, and JSS/SXA.
• Familiarity with Azure PaaS, containers, and cloud-native development for Sitecore deployments.
• Experience with content serialization and migration tools (Sitecore CLI, Sitecore Content Serialization, Unicorn).
• Ability to architect scalable, high-performing technology solutions with a focus on maintainability and security.
• Ability to work within a collaborative team environment.
• Deep experience with source control tools like Git and modern CI/CD pipelines.
• Experience leveraging AI-assisted development tools (e.g., GitHub Copilot, ChatGPT Codex, or similar) to accelerate coding, improve code quality, generate test cases, and streamline documentation.
• Desire to learn continuously and mentor junior developers.
• Ability to write technical documentation and create application flow diagrams to be used by the development team during programming stages.

• 7+ years of professional programming experience required.
• Strong communication skills (both in person and in writing).
• Experience with modern data management practices.
• Strong planning and solution architecture skills.
• Solid grasp of web security concepts.
• Experience with Agile methodology and collaborative workflows.

• Sitecore Professional Developer Certification, Sitecore XM Cloud or Sitecore 10+ certification.
• Exposure to modern front-end frameworks (React, Next.js, Angular) for headless Sitecore implementations.
• Knowledge of Sitecore composable products (Content Hub, Personalize, Search).Experience using AI tools for content migration, code refactoring, or QA automation.
• Basic server administration and networking knowledge.
• Firm grasp of modern best practices for analytics, SEO, user experience, and online marketing strategies.