Back End Developer Sitecore Web Security Service

As a Back-End Developer focused on Sitecore XM 10.2 security and stability, the consultant will strengthen the resilience of Elia Group's digital platforms. The consultants work will ensure that our websites and communication systems are secure, performant, and ready to transition toward Sitecore XM Cloud.

The consultant will collaborate closely with architects, DevOps engineers, and IT Security teams to implement secure coding practices, improve platform performance, and ensure full compliance with Elia's security policies.

Key Responsibilities:

· Maintain and stabilize the existing Sitecore XM 10.2 platform until cutover to XM Cloud.

· Implement and continuously improve secure development practices for Sitecore and .NET.

· Perform vulnerability scanning, patching, and remediation for Sitecore instances, pipelines, and modules.

· Conduct regular code reviews with a focus on performance, scalability, and security.

· Align with solution and security architects on technical standards and architecture evolution.

· Optimize platform performance through caching, database tuning, and CDN/WAF improvements.

· Strengthen observability by enhancing monitoring, logging, and alerting (e.g., Application Insights, Azure Monitor or similar application).

· Participate in the definition and adoption of SLA/OLA, incident, and change management processes.

· Ensure coexistence readiness with XM Cloud - including content parity validation, cache/purge coordination, and unified incident communication.

· Support the feature freeze policy on legacy XM 10.2: only security, compliance, and stability fixes unless approved via CAB.

· Stay current with emerging web security standards, Sitecore patches, and .NET frameworks.

· Document all technical and security changes following Elia's governance and audit requirements.

Do you have experience in Writing skills?, Do you have a Master's degree?, · Bachelor's or Master's degree in Computer Science, Information Technology, or equivalent professional experience.

· Minimum of 5 years recent experience in Sitecore back-end development with a security and performance focus.

· 5+ years of professional experience in back-end development with C#/.NET.

· Proven experience with Sitecore XM 10.2 (installation, pipelines, configuration, patching, and performance optimization).

· An excellent knowledge of English and a basic knowledge of French and/or Dutch

· Strong knowledge of web application security principles (OWASP, secure headers, encryption, CSRF, XSS prevention).

· Experience with DevOps & CI/CD pipelines for Sitecore deployments (Azure DevOps, GitHub Actions, or similar).

· Experience with working with Sitecore XM 10.2 on-premises with manual deployment procedure

· Hands-on experience with SQL Server performance tuning and Sitecore content delivery scaling.

· Experience with WAF/CDN configurations in combination with Traditional Sitecore XM 10.2 on-premises (e.g., F5, Azure Front Door, Cloudflare).

· Practical knowledge of application observability tools such as Application Insights, Seq, Kibana, or similar software.

· Excellent collaboration skills; ability to work effectively with architects, DevOps, and security teams.

· TOGAF 10.2 understanding and document writing skills

· 5+ years of hands-on Sitecore C# experience

· Familiarity with DevOps practices and tools for Sitecore deployments.

· Strong problem-solving and analytical skills.

· Excellent communication and collaboration skills.

· Ability to work independently and as part of a team.

· Understanding of infrastructure (on-prem + cloud combination)

· Passion for learning new technologies and staying up to date with industry trends, * Has the consultant had at least 3 years of recent experience in Sitecore back-end development with a focus on security and performance?

• Has the consultant demonstrated strong knowledge of web application security principles?