Software Engineer Waltham, MA

Xometry (NASDAQ: XMTR) powers the industries of today and tomorrow by connecting the people with big ideas to the manufacturers who can bring them to life. Xometry’s digital marketplace gives manufacturers the critical resources they need to grow their business while also making it easy for buyers at Fortune 1000 companies to tap into global manufacturing capacity.

Thomasnet, part of Xometry, is the industrial platform where millions of buyers find and source from North American manufacturers and suppliers.

We are seeking a Staff Software Engineer to join Thomas engineering. As a senior individual contributor, you will guide software implementation across several engineering teams and influence decisions across our technology organization. Thomas is moving from a traditional supplier directory to AI-assisted sourcing, and you will set technical direction for the shared systems and AI infrastructure that this shift depends on, while staying hands-on in the code.

• Hands-on technical leadership. Write and review architectural plans for new projects, then participate in implementation with the teams.
• Guide innovation. Champion a good mix of proven and cutting-edge technologies and methods. Know when to change course and when to double down on what already works, including how we adopt AI across the platform.
• Teaching and mentorship. Serve as a mentor and guide to engineers across the organization, helping them grow their skills.
• Code review. Do code review and mentor others across the org to perform good code reviews.
• Operational excellence. Deliver reliable, high-quality software that exceeds customer expectations and aligns with business timelines.
• Collaborative strategy. Build strong partnerships with product managers, designers, and leadership to promote open communication, strong collaboration, and high standards.

• 10+ years of professional software development experience, with a track record of owning outcomes, setting technical direction across teams, mentoring engineers at all levels, and influencing product and business decisions.
• Strong full-stack engineering skills that are transferrable to our stack: backend services in Type Script and Node.js with GraphQL APIs, a React and Next.js frontend, PostgreSQL and analytical data stores, and search such as Open Search, at production scale. Comparable experience in another modern stack counts just as much; prior experience with our exact tools is not required.
• Hands-on experience with the engineering behind AI products: LLM applications, retrieval-augmented generation, vector search, or embedding models. We hire AI-native engineers who build with these tools and judge their output rigorously, whatever the specific frameworks.
• Depth in areas our platform is growing into, such as multimodal (image and text) embeddings and search, agent orchestration frameworks (e.g. Lang Graph, Lang Chain), model fine-tuning and adaptation, with deep learning frameworks such as PyTorch or Tensor Flow.
• A fast learner with high agency who works fluently in an AI-native development environment and shares what they learn. We are all still learning how to build with AI, and we want people who help the team learn faster.
• Marketplace or multi-sided platform experience is highly desirable, with an understanding of scaling shared platforms.
• Excellent communication and collaboration, comfortable engaging with both technical and non-technical stakeholders, from junior ICs to executives.

We offer a competitive benefits package, including 401(k) match; medical, dental, and vision insurance; life and disability insurance; generous paid time off including vacation, sick leave, floating and fixed holidays, maternity…