Fulltime Freelance Software Developer Jobs in Riverside, CA

ETAP empowers customers to make informed decisions throughout the life cycle of their projects with innovative software solutions for electrical systems. By applying ETAP solutions, customers experience continuous intelligence during design and engineering and into operations and maintenance using a unified electrical digital twin platform. ETAP supports customers in their digital transformation and sustainable energy transitions for a green and smart future, helping them to prioritize safety, maximize reliability, and stay resilient.

Our employees' passion for excellence, innovation, and customer satisfaction is our most-prized resource. If you share that passion - and want to be part of a company that leads the energy transition towards a cleaner and more resilient world for future generations - we invite you to join us!

ETAP is committed to creating a diverse work environment and is proud to be an Equal Opportunity Employer.

Job Title:Senior Software Engineer

Location:Irvine, CA

Employment Type: Full-Time/ Hybrid

We are seeking a Senior Software Engineer to lead the design and development of our Microgrid Controller (MGC) platform. This role sits at the intersection of systems architecture, real-time controls, Linux engineering, and distributed energy systems, and plays a key role in advancing how modern microgrids are monitored and controlled globally.

You will work on improving system reliability, performance, security, and scalability across the MGC platform, including Linux (RHEL 9.x) environments, APIs, networking, databases, and automated testing frameworks.

• Design and enhance the MGC Linux (RHEL 9.x) platform for high reliability and performance
• Develop APIs and firmware-level REST integrations for scalable system deployment
• Work with Docker-based containerization and deployment workflows
• Integrate and support industrial communication systems and protocols
• Optimize network configuration including routing, firewalls, and security
• Build and maintain MongoDB and SQL-based data systems for telemetry and persistence
• Implement cybersecurity and system hardening across components
• Develop CI/CD pipelines and automated testing frameworks
• Collaborate with cross-functional teams and mentor junior engineers

• 7+ years of software engineering experience
• Strong experience in C#, .NET Framework, and WPF
• Solid Linux (RHEL preferred) system integration experience
• Experience with REST APIs, Docker, and MongoDB
• Background in CI/CD, system integration, and automation testing

• Python
• Experience with industrial protocols (Modbus, DNP3, IEC 61850)
• Exposure to distributed control systems or embedded/Linux environments
• Knowledge of cybersecurity in critical infrastructure systems
• Strong leadership and mentoring experience

• Opportunity to shape next-generation microgrid technology
• Global, innovation-driven engineering environment

Salary Range: 113,500.00 - 170,500.00 USD Annual

This pay range represents the minimum and maximum compensation that the position offers, and final compensation can vary within the range depending on work location, job experience, skills, and relevant educational attainment and/or training.

ETAP requires all successful applicants to undergo and pass a comprehensive background check before they start employment. Background checks will be conducted in accordance with local laws and may, subject to those laws, include proof of educational attainment, employment history verification, proof of work authorization, criminal records, identity verification, credit check. Certain positions dealing with sensitive and/or third party personal data may involve additional background check criteria.

ETAP is an Equal Opportunity Employer. We are committed to being an exemplary employer with an inclusive culture, developing a workplace environment where all our employees are treated with dignity and respect. We value diversity and the expertise that people from different backgrounds bring to our business.

Come and join ETAP to create the transformative technology that enables our customers to engineer a better world.