Senior Software Engineer - Fountain One

Role overview

Senior Software Engineer (Fountain One) at Fountain, joining the platform team responsible for foundational systems that power the Fountain ecosystem. You’ll work as part of a compact platform squad (currently four engineers) in an agent-first engineering organization where coding and review agents are integrated into the daily workflow.

Responsibilities

• Ship platform capabilities across customer and internal products
• Own performance, security, and stability for high-traffic production systems
• Enhance agentic systems, including coding agents and observability tools
• Lead architectural decisions for human and agentic interfaces
• Design reliable code, APIs, and contracts for humans and agents
• Collaborate with product and engineering teams to deliver customer impact
• Work autonomously with product managers and designers, operating like an early-stage product team
• Identify problems, ship fixes, and own outcomes

Requirements

• 5+ years in professional engineering, primarily backend development, with experience launching production-ready systems
• Expert systems design skills and strong architectural judgment
• Track record of identifying and re-engineering misaligned systems
• Excellent discernment for technical trade-offs, plus practical awareness of UX, APIs, and code quality
• Demonstrated experience with agentic or LLM-based systems beyond consumer use (e.g., LLM in the critical path, tooling agents consume, or evals to catch regressions)
• Initiative and comfort shipping unprompted improvements that prove valuable
• Thrives in autonomous, ambiguous environments (minimal reliance on ticket queues)
• Excellent written communication for async collaboration across time zones

Nice to have

• Experience designing APIs/tools intended to be consumed by agents (e.g., structured outputs, deterministic surfaces, observability)
• Experience in early-stage product teams/startups
• Proficiency with event-driven architectures, monorepos, and platform-level observability

Remote / work style

• Team collaboration across EU, US, South Africa, and India with strong async practices
• Mentions flexibility to work from wherever you choose, with some in-person connection expectation (details truncated)