[Hiring] Principal Back End Engineer @Modus Create

Role Description

Modus Create is seeking a Principal Java Software Engineer to lead the design and delivery of complex, high-performance backend systems. You'll own greenfield Spring Framework components from architecture through production, setting technical direction for the engineering team while staying hands-on with critical implementation work. This is a role for a deeply experienced Java architect who can navigate ambiguity, mentor engineers, and deliver production-grade systems that handle extreme scale and throughput demands.

• Be a technical leader within the Software Engineering team, multiplying your impact through architecture, mentorship, and decisions that shape how we build.
• Work alongside experienced engineers who respect technical rigor, challenging decisions and raising architectural concerns with confidence.

Qualifications

• 10+ years professional Java development with deep, hands-on experience across the full platform stack.
• Expert-level knowledge of the Spring Framework ecosystem (Spring Core, Spring Boot, Spring Data, Spring Security, Spring Cloud) with experience architecting large-scale applications using these libraries.
• Proven track record designing and building greenfield Spring applications that handle high request volumes and extreme throughput; not just maintenance work, but architecture from the ground up.
• JVM expertise: configuration, tuning, garbage collection, memory management, and performance optimization in production systems.
• Experience designing and implementing robust API integrations including OAuth 2.0, error handling strategies, retry logic, progressive backoff, and circuit breaker patterns.
• Experience creating AI-powered applications, integrating with AI tools and services, or creating or using MCP servers.
• Hands-on cloud platform experience—deploying, configuring, troubleshooting, and optimizing applications in production cloud environments.
• Demonstrated mentorship of engineers; ability to elevate team technical capability through code review, pairing, and guidance.
• Strong collaborative mindset; comfortable operating in flat team structures and advocating for technical decisions without requiring process scaffolding.
• Experienced using AI-assisted coding tools (GitHub Copilot, Claude, etc.) with human-in-the-loop best practices; able to leverage AI for accelerated delivery while maintaining code quality, security, and architectural integrity.
• Track record of shipping production systems; able to balance architectural ideals with delivery constraints and business timeline.

Requirements

• Design and architect complex Spring Framework components for greenfield systems; make trade-off decisions balancing performance, maintainability, scalability, and time-to-delivery.
• Own end-to-end delivery of critical backend features, including implementation, testing, performance validation, and production support.
• Research and evaluate emerging Java and Spring Framework technologies; prototype new patterns and tools and recommend adoption when justified.
• Implement best practices for high-load systems: API gateway patterns, resilient integrations, efficient database access, caching strategies, and observability.
• Conduct technical design reviews with engineering peers; identify architectural risks and propose solutions.
• Mentor engineers through code review, pair programming, and technical guidance; model problem-solving approaches and engineering discipline.
• Contribute to team standards: code quality, testing practices, deployment patterns, documentation; lead by example rather than policy.

Benefits

• Architecting systems that scale; owning the decisions that let an application handle 10x load without falling over.
• Solving hard problems in Spring and the JVM; diving deep into performance bottlenecks, concurrency issues, and integration challenges.
• Mentoring engineers and watching them grow; knowing that your guidance directly improved their capabilities and career trajectory.
• Building clean, maintainable code that teams will want to own and evolve; seeing your architectural choices simplify future work.
• Exploring emerging technologies (Spring AI, MCP servers, new JVM runtimes) and deciding when they're worth adopting versus when they're noise.

What Success Looks Like

• You've shipped at least one greenfield Spring application that handles production traffic at significant scale (hundreds of requests per second, petabyte-class data volumes, or equivalent complexity).
• Engineers on your team can articulate the architectural decisions behind the systems you've built and why those decisions were made.
• Your code reviews result in better code and better engineers; reviewees understand not just what to change, but why.
• Your team ships faster and with higher confidence because they have clearer architectural patterns and fewer re-do cycles.
• You've successfully integrated third-party APIs at scale; your error handling and resilience patterns have proven themselves under real failure conditions.