Full Stack Software Engineer

O3 Solutions provides a digital project management platform purpose-built for capital projects. Driven by industry best practices, including Advanced Work Packaging (AWP), Agile, and Lean methodologies, O3 helps teams of all kinds achieve measurable success from early phase planning through execution, systems completion, and start up. At O3, we are committed to building a team of talented, passionate individuals who are dedicated to reshaping the future of the construction industry. Our people are the driving force behind everything we achieve, and we’re always looking for exceptional talent to join us on our journey. The Role We’re looking for a Full Stack Software Engineer who can own a feature from database to UI and help raise the bar for the rest of the team. You’ll work across the entire stack in a modern .NET / Angular environment, drive technical design decisions, participate fully in Agile ceremonies, and collaborate closely with product, UX, and client success. This isn't a role where you pick up tickets and disappear. We expect you to understand context, ask good questions, and care about what ships. What You'll Work On Design and develop new features across the full stack from SQL schema through business logic to Angular UI Troubleshoot, diagnose, and fix issues across the existing codebase, from UI behavior down to database performance Lead technical design discussions and own architecture decisions for the features you build Mentor other engineers through pairing and design feedback Take full ownership of code you ship: write thorough unit tests, review your own work critically, and anticipate upstream/downstream effects before opening a PR Participate actively in peer code reviews with a focus on correctness and long-term maintainability Contribute to sprint planning, retrospectives, and scope assessments. Your input on timelines matters. Support teammates and contribute to a culture where the bar stays high The Stack Business / API Layer: C#, ASP.NET, REST, Repository Pattern UI: Angular Data Layer: MSSQL, Entity Framework Testing: MSTEST, Jest What We’re Looking For Required Bachelor’s in Computer Science or related field + 8+ years of experience, OR 10+ years of equivalent full-time professional experience Experience building and shipping commercial B2B software, ideally at an independent software vendor (ISV) Expert-level object-oriented design and architecture skills in .NET / C# Deep experience designing and building REST APIs with ASP.NET Extensive JavaScript development experience with a modern frontend framework, Angular strongly preferred Strong SQL proficiency and solid experience with relational databases Strong testing discipline and a habit of writing thorough unit tests Willingness to make AI coding tools like Claude Code or GitHub Copilot part of your daily workflow Nice to Have Cloud platform experience (AWS or Azure) Automated testing experience (UI, API, integration) Construction or industrial domain knowledge SQL Server (MSSQL) and Entity Framework experience, including advanced skills like execution plan analysis, query tuning, and T-SQL 3D modeling or graphics experience, such as Autodesk tools and APIs or three.js Experience mentoring engineers and leading feature design from concept to production Benefits Remote work Unlimited PTO Results Only Work Environment (ROWE): flexible schedules, no micromanagement Medical, Dental & Vision Insurance Life, AD&D & Long-Term Disability coverage 401(k) Plan & Matching Professional development support Why O3 Construction is a multi-trillion dollar industry that still runs on spreadsheets and tribal knowledge. We're changing that. If you want to build software that has a real, visible impact on how the world gets built, and do it on a team where your name is on the work, this is the right place. Additional Information