About the Role

As a Fullstack Engineer at Mosaic, you'll build product experiences that investors and bankers rely on to run high-stakes deal processes. You'll work across the stack-from sleek, high-trust interfaces to backend services that power modeling, ingestion, collaboration, and workflow automation.

This is a role for builders who want real ownership. You'll ship features end-to-end, collaborate tightly with product and design, and help establish the technical foundations for a platform used in mission-critical environments. You'll tackle challenging problems like structured financial computation, document ingestion, auditability, permissions, real-time collaboration, and performance at scale.

Your work will directly impact how the world's most sophisticated financial teams evaluate acquisitions, credit investments, and major corporate decisions.

Key Responsibilities

Build End-to-End Product Experiences

• Own features from idea 12 design 12 implementation 12 testing 12 deployment
• Build intuitive, polished UI workflows that feel fast and trustworthy
• Ship backend APIs and services that support complex user actions and data flows

Design Systems that Scale

• Improve the architecture of core systems powering modeling and analysis
• Write clean, maintainable, well-tested code that raises the team's bar
• Ensure performance and reliability for workflows used in live deal environments

Work in a High-Trust, High-Accuracy Domain

• Build with auditability and correctness in mind
• Help define patterns for permissions, versioning, and reproducibility
• Balance velocity with quality in a product where accuracy matters

Collaborate Deeply with Product & Customers

• Partner with product, design, and GTM teams to translate needs into product
• Incorporate feedback from real customer workflows (often built in Excel)
• Contribute to roadmap shaping through technical insight and execution

Drive Engineering Excellence

• Participate in code reviews, technical design discussions, and system planning
• Improve developer tooling, observability, and internal infrastructure
• Help define best practices as the engineering org scales

Who We're Looking For

Fullstack Product Builder

• 2-6+ years of experience building modern web applications
• Comfortable working across frontend + backend and owning features end-to-end

Strong Frontend Fundamentals

• Experience building clean UIs with modern frameworks (React preferred)
• Strong instincts around usability, quality, and UI performance

Backend & Systems Capability

• Experience building APIs and services (Node, Python, Go, etc.)
• Strong data modeling instincts and comfort working with relational databases
• Familiarity with cloud infrastructure and production systems

High Ownership / Startup Mentality

• Self-starter who thrives in fast-moving, unstructured environments
• Bias toward action, shipping, and iterating quickly with the team

Thoughtful Collaborator

• Clear communicator who enjoys working cross-functionally
• Excited to pair, review code, and build internal momentum

Bonus (Not Required)

• Experience building tools for finance, analytics, or high-compliance workflows
• Familiarity with AI product patterns (LLMs, agents, structured extraction)
• Experience with workflows involving spreadsheet-like interactions
• Exposure to observability tooling, performance profiling, or infra work

Why Join Mosaic?

• Build the AI-powered modeling and workflow platform for private markets
• Work on hard technical problems with real-world stakes and complexity
• Join a team of top-tier operators across finance and technology
• Have major product and technical influence as the company scales
• Ship software that immediately impacts how the world's top firms make decisions
• Play a key role in shaping Mosaic's product roadmap and influencing its growth.
• Enjoy opportunities for career growth and leadership in a dynamic, fast-paced environment.
• Make a tangible impact by helping customers succeed and drive innovation in the industry.

What's in it for you?

This is a full-time position with:

• A competitive base salary; and
• An early-stagestart-up equity package designed to create life-changing wealth when we win as a team.

Other Perks & Benefits:

• 9B7 Health, vision & dental coverage
• Unlimited PTO
• 6A0 Unforgettable team building events, offsites, and happy hours (Feel free to ask about it during the interview )

If you find yourself waking up every day seeking:

• To be challenged by your peers
• To grow your skillset in building technology businesses
• To experience the joys, learning opportunities, and growing pains of doing something completely new
• To have a shot at a generational wealth creation event

...then Mosaic is definitely the place for you.

We're looking to hire people who take ownership, communicate openly, have an entrepreneurial mindset, and are excited to bring a totally new technology to an incredible industry. We encourage all candidates to apply even if your experience doesn't exactly match up to our job description.