Backend Product Engineer (Fintech)

TL;DR

Backend Product Engineer (gRPC/API): Designing and evolving core domain APIs and data models for a large-scale prediction market platform with an accent on real-time streaming and system unification. Focus on building gRPC/Connect services, implementing WebSocket-to-gRPC migrations, and delivering consumer-facing features like personalization and live data feeds.

Location: On-site in New York

Company

Polymarket is the world's largest prediction market platform, aggregating diverse opinions into transparent, market-based probabilities.

What you will do

• Design and evolve core domain APIs and data models to support the consumer product at scale.
• Develop real-time infrastructure using gRPC/Connect, WebSockets, and event/notification systems.
• Collaborate with frontend, mobile, and product teams to ship features like search and personalization.
• Consolidate fragmented services and APIs into clean, reusable primitives.
• Balance the cleanup of technical debt with the delivery of high-priority product features.
• Work cross-functionally with infra and data teams to ensure tight platform integration.

Requirements

• Experience designing and evolving domain APIs and data models for scale consumer products.
• Hands-on expertise with gRPC/Connect and real-time streaming infrastructure.
• Proven track record of shipping end-user features in collaboration with cross-functional teams.
• Ability to unify fragmented APIs into clean, reusable primitives.
• Pragmatic approach to managing technical debt under tight deadlines.
• Location: Must be based in New York (On-site)

Nice to have

• Experience at a high-growth consumer product company or marketplace.
• Experience with cloud environments (AWS/GCP) and containers.

Culture & Benefits

• Competitive salary and equity.
• Unlimited PTO.
• Comprehensive Health, Vision, and Dental coverage.
• 401k match.
• High-end hardware setup (MacBook Pro, large display, and accessories).