Principal Software Engineer

Endgame labs, inc.
United States
1 day ago
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Role details

Contract type
Permanent contract
Employment type
Full-time (> 32 hours)
Working hours
Regular working hours

Tech stack

JavaScript (Programming Language) Application Programming Interfaces (APIs) Artificial Intelligence User Authentication Data Systems Cursor Database Design Design of User Interfaces Human-Computer Interaction Python (Programming Language) Microsoft OneNote Redis
+14 more
Microsoft Copilot Salesforce.Com Software Engineering Systems Architecture TypeScript ReactJS Large Language Models Claude Code AI Coding Agents Agentic-AI Rate Limiting Stripe Front End Software Development Airtable

Job description

Revenue teams at Monte Carlo, BetterUp, Braze, and dozens of other leading companies use Endgame as their source of truth. Instead of context scattered across fifteen disconnected systems, their reps, managers, and CS teams - and the agents working alongside them - all operate from the same structured view of every customer and every deal.

Weve raised $47.5M from EQT Ventures, Menlo Ventures, Upfront Ventures, and Unusual Ventures, plus executives from Zoom, Stripe, Notion, and Airtable. Were a team of ~25, mostly engineers, and we build production systems with real architecture - not prototypes.

How we build ️

Were an AI-native engineering team. Agentic coding tools are integral to how we build and ship 15-20 times daily, if not more. We build with Claude Code, Cursor, and Copilot, and were constantly sharing what works and what doesnt. We move fast, were not afraid to throw things away, and we keep the bar high because customers depend on us. Youll help push that culture forward.

What youll do

  • Build and evolve the MCP server and agent tool surfaces that AI clients use to query Endgames context graph - designing tool schemas, managing context windows, and making sure every tool call returns the right data fast.
  • Ship the frontend features, tRPC routes, and React components that customers interact with daily - from admin dashboards to the core product UI.
  • Design and harden the public API layer: authentication, Redis-backed rate limiting, quota enforcement, and the observability to know when something goes wrong.
  • Wire new data sources into the product by integrating with the context graph and making that data available through both human-facing UI and agent-facing tool surfaces.
  • Translate ambiguous product goals into concrete engineering scope, then ship it. Youll work closely with product, design, and the rest of engineering, and youll often be the person turning a customer pain point into a novel solution.
  • Own end-to-end quality on the surfaces you ship: performance, reliability, security, observability. AI raises the floor, your taste raises the ceiling.

Requirements

Software Engineering, Artificial Intelligence (AI) Agents, Production Systems, Prototyping, System Architecture, Artificial Intelligence (AI), MCP - Microsoft Certified Professional, Database Design, User Interface/Experience (UI/UX), Reporting Dashboards, * Deep understanding of the TypeScript and JavaScript ecosystem. Youve built and maintained serious systems in it, not just touched it.

  • Familiarity with Python.
  • Experience designing and implementing LLM and agent tool surfaces, including the tools themselves and the context management around them.
  • Experience developing APIs with a real focus on observability and authentication.
  • Strong product instincts. You can take an ambiguous product requirement and translate it into deliverable engineering scope.
  • Deep experience with agentic coding tools and modern testing practices. You use AI coding tools daily, have opinions about them, and know when to trust the agent versus reading the diff yourself.
  • You default to collaborative action. You write, you share early, you make decisions reversible when you can.
  • Bonus: prior experience with revenue-data systems (Salesforce, CRMs, sales tooling) or developer-platform infrastructure (SDKs, APIs, agent tooling).

Benefits & conditions

  • Competitive compensation and equity
  • 401k, health, dental, and vision insurance
  • Flexible time off
  • Paid parental leave
  • Education stipend

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