Senior Software Engineer- Full Stack in Centennial, Colorado at Daxko

Daxko builds the software that powers fitness, wellness, and community organizations—everything from member management and payments to digital engagement and analytics. From small studios to the largest associations, we help thousands of fitness businesses streamline operations, enhance member experiences, and drive sustainable revenue growth.
This role sits at the intersection of legacy modernization and modern product development. You'll work across a multi-generation codebase, helping move business logic off older systems and into cleaner, testable services, while also building new product experiences used by fitness and wellness organizations every day. You'll need to go wide and deep: database performance, backend APIs, frontend UX, deployment pipelines, and AI-assisted development workflows are all in scope. If you do your best work when you can see the whole system and make pragmatic decisions in a complex environment, this role is built for you.
What you'll do

• Build and maintain REST APIs in Java and Spring Boot, consolidating legacy code into modern domain packages across multiple API generations
• Own the full data access layer: query tuning, JPA specifications, Flyway migrations, and performance-sensitive reporting paths in SQL Server
• Build product experiences in a pnpm monorepo using React, TypeScript, Vite, and MUI, with TanStack Query and Zod handling data fetching and validation
• Read, debug, and incrementally replace behavior in the ColdFusion codebase, retiring legacy paths safely as modern services come online
• Package and deploy services with Docker and GitLab CI, working across AWS (S3, DynamoDB, KMS) and Kubernetes
• Contribute to integration and unit testing using JUnit, WireMock, Vitest, and Playwright/Selenium
• Mentor teammates, deliver actionable code reviews, and help define engineering patterns across backend, frontend, and platform concerns

What you'll bring

• 7+ years of professional software engineering experience with meaningful full-stack ownership
• Solid production experience with Java and Spring Boot, including REST API design and service-layer architecture
• Strong React and TypeScript skills in real, modern single-page applications
• Deep SQL Server experience, including query optimization, indexing strategy, and diagnosing slow paths in production
• A track record of working in complex legacy systems: tracing cross-service behavior, shipping incremental improvements, and not breaking things
• A testing discipline that spans unit, integration, and UI automation layers
• Clear communication, both in code review and cross-functional conversations where you can explain tradeoffs without leaning on jargon

Nice to have

• Experience migrating off legacy platforms like ColdFusion or similar
• Familiarity with OpenAPI-first development and contract-driven frontend/backend integration
• Background in containerized delivery (Docker, Kubernetes) and CI/CD tooling
• Experience with multi-tenant SaaS patterns, distributed tracing, or message-driven architectures like RabbitMQ or Kafka

Work ArrangementHybrid schedule with 1 day per week in-office for collaboration, planning, and team connection. Remote-friendly the remainder of the week, with the expectation of overlap with team working hours and participation in code review, incident response, and planning.
Additional Information:Daxko is dedicated to pursuing and hiring a diverse workforce. We are committed to diversity in the broadest sense, including thought and perspective, age, ability, nationality, ethnicity, orientation, and gender. The skills, perspectives, ideas, and experiences of all of our team members contribute to the vitality and success of our purpose and values. We truly care for our team members, and this is reflected through our offices, and benefits, and great perks. These perks are only for our full-time team members.
Some of our favorites include:
🏝 Flexible paid time off ⚕️ Affordable health, dental, and vision insurance options💪 Monthly fitness reimbursement🤑 401(k) matching🍼 New-Parent Paid Leave👖 Casual work environments🏡 Flexible work options - remote & hybrid
All your information will be kept confidential according to EEO guidelines.
#LI_Hybrid
Where you fall within the compensation range is based on how you demonstrate the skills and competencies needed for the role. We typically reserve the upper half of our compensation bands for team members who have grown within Daxko. In addition to base salary, some roles may be eligible for bonuses, commissions, or other performance-based incentives. We also offer a comprehensive benefits package, recognition programs, and plenty of opportunities to grow your career with us.
The pay range for this role is $110,800 – $159,600 per year.