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Principal Full-Stack Developer, New York

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ion design

B2B

Principal Full-Stack Developer, New York

New York
On-site
Full-time
Posted Feb 3, 2026
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Lab49
Software Engineering
On-site
Lab49 is an award-winning specialist consultancy that creates bespoke technology in partnership with the most important companies in finance.   We were founded in 2002 to bring Silicon Valley solutions to Wall Street’s door. Since then, we have worked on successive waves of technological change, including distributed computing, high-speed automation, enterprise UX and digital distribution (for which Lab49 was among the first significant practices established on Wall Street), DevOps, cloud and data science.    Today, we are an established partner in financial markets, having delivered hundreds of projects for clients including all the world’s tier-one investment banks and many of the largest buy-side firms globally.    Being part of Lab49 means bringing your drive and creativity into an environment where your contributions will make immediate impact. Engineers will work in cross functional teams, consulting directly with our clients, shaping not only technical solutions to business problems but delivering them into production.  The Principal Full-Stack Developer will play a critical leadership role on a key project for a strategic Lab49 client. Working in a collaborative cross functional project team, with direct client-facing interactions, you will have an opportunity to lead a team of engineers and build modern digital products.

What you’ll be doing:  

  • Partnering with our client to lead the design and build of a structured products trading UI using modern web development technology and techniques. You will be responsible for managing engineering deliverables, and the relationships with other key contributors to deliver great software. 
  • Design, document, and plan for the technical implementation and delivery of working software into production. 
  • Act as a hands-on engineer and architect to support ongoing project work. Lead and actively participate in projects, serving as a role model for project teams and collaborating with other practices to ensure successful outcomes. 
  • Partner with client counterparts and stakeholders to maintain and build relationships, maintaining a commercial approach. Develop strong relationships with clients as a strategic partner and technical advisor, contributing to expanding our footprint and securing follow-on work. 
  • What you should have: 

  • 12+ years of solid hands-on experience with C#/.Net and Python development.
  • 5+ years of experience with React and modern front-end state management.
  • Extensive experience architecting solutions on AWS, including Terraform and Docker.
  • Proven track record operating effectively inside large, complex organizations (e.g., Tier-1 Investment Banks or Global Asset Managers).
  • Deep understanding of SQL and data persistence strategies at scale.
  • Fluency with modern C# features and a strong grasp of software design patterns and distributed systems.
  • BS in Computer Science or equivalent experience.
  • Expert-level knowledge of, and strong demonstrated interest in, global financial markets and financial products.
  • Apply for this role
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    ion design

    Company profile

    We built the 1st Autonomous AI Product Designer

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    Headquarters

    San Francisco, CA, USA

    Team size

    1-10

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