Principal Software Engineer

Open Solar was founded in 2017 by global pioneers in solar software - Andrew Birch and Adam Pryor. Open Solar exists to accelerate the adoption of solar and renewable energy globally. We provide the world's clean energy professionals with an end-to-end digital design, sales and management software to grow their businesses, free of charge.

Open Solar is driven by its mission to accelerate the adoption of solar for a world powered by sunshine by 2050. We stay focused on our mission by obsessing over the experience of our end users, being open and honest, solving problems through careful and deliberate design, and by keeping things simple.

Open Solar is a truly global organisation with our team spread across 12 countries and our user base spread over 185+ countries. Find out more about our world class crew here:

At Open Solar, we are dedicated to cultivating a workplace that celebrates diversity and promotes inclusivity. Our goal is to build a team that is reflective of the communities we serve, recognising that diversity brings strength and richness to our organisation. We believe that everyone should feel empowered to bring their authentic selves to work and we are committed to creating an environment where all employees are valued, respected, and supported.

We actively seek to attract and retain a talented workforce that represents the breadth of our society. We provide equal opportunities for everyone to thrive and advance in their careers, enabling them to achieve their full potential.

This is your opportunity to be part of the clean energy movement, creating a lasting impact on the world. All while being part of a passionate, fun, and highly collaborative team.

The Principal Software Engineer (Full Stack) role is a full-time permanent position located in the United Kingdom and is a remote working role.

You will have the opportunity to be part of a global high-performing dynamic software team, doing what you do best.

The role is focused on designing and building the best solutions for our users in over 185 countries, whilst maintaining best practices in software development.

• Design and implement robust, scalable, and secure full-stack solutions using React / Python / Django / MySQL.
• Own architecture decisions for complex systems, ensuring long-term maintainability and scalability.
• Collaborate with product managers, designers, and engineering leadership to define and drive technical strategy and roadmap.
• Lead cross-functional technical initiatives, including performance optimisations, system refactoring, and migrations.
• Establish and enforce engineering best practices across the organisation (code quality, security, testing, CI/CD).
• Mentor and coach engineers and senior engineers, fostering professional growth and technical excellence.
• Conduct and facilitate design reviews, code reviews, and technical deep dives.
• Drive innovation by evaluating and introducing new technologies, frameworks, and methodologies.

• 12+ years of relevant experience in the core technology skills, including substantial leadership and architecture responsibilities.
• Core Technology skills required – Strong full stack software engineering skills.
• Best practice software development skills and practices.
• Excellent communication skills with an open, collaborative approach.
• A passion for problem solving and challenges.
• The desire to positively contribute to shaping organisation culture and be part of a diverse team.
• A good understanding of consumer finance, B2C payments and integrated e-commerce solutions is preferable.

• A Passionate, Driven, and Highly Collaborative Team: Join a team that is dedicated to making a difference, where collaboration and passion drive our success.
• Mission-Focused Organization with a Well-being-Led Culture: We prioritize both our mission to drive clean energy solutions and the well-being of our team members, fostering a supportive and healthy work environment.
• Diverse, Equitable, and Inclusive Work Environment: We celebrate diversity and inclusivity, creating a workplace where everyone's contributions are valued and respected.
• Professional Development and…