Senior Software Engineer - Fountain One

Fountain; San Francisco (CA); On-site; USD 180,000 - 240,000; Full time

Benefits offered by this job

Flexible vacation policy

Paid holidays

Monthly lunch stipends

Ongoing education allowances

Home office reimbursement

Cell phone reimbursement

Wellness reimbursement

Job summary

Fountain is hiring for a backend-focused engineer to help scale our workforce management platform. You will own production-grade systems, drive architectural decisions for human and agentic interfaces, and collaborate with product and design teams to deliver impact for hundreds of customers worldwide.

The role emphasizes autonomous work in a fast-paced environment, with an emphasis on performance, observability, and secure, reliable APIs used by agents and humans alike.

Qualifications

• 5+ years in a professional engineering role focusing on backend development.
• Strong track record of launching production-ready systems.
• Experience with agentic or LLM-based systems beyond consumer use.

Responsibilities

• Ship platform capabilities across all customer and internal products.
• Own performance, security, and stability for high-traffic production systems.
• 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.

Skills

Backend development

Systems design

LLM-based systems

Architectural decisions

Job description

When you join the Fountain team, you become part of the leading enterprise solution for frontline workforce management. Fountain’s automated, customizable platform provides a seamless applicant experience for workers, while ensuring organizations can scale and manage their frontline talent.

We’ve helped hundreds of companies like UPS, CLEAR, Stitch Fix, GoPuff, Fetch, and sweetgreen to hire, onboard, and manage over 14 million workers in more than 75 countries.

In 2022, we closed $185M in our Series C, led by SoftBank and B Capital.

Join our growing team of highly collaborative, ambitious, and forward-thinking Fountaineers as we empower our hundreds of customers and millions of frontline workers around the world.

Let’s elevate frontline work together.

Fountain builds workforce management software for the world's largest hourly employers. We are an agent-first engineering organization where coding and review agents are integrated into our daily workflow. Our platform team builds the critical systems that enable engineers and agents to ship dependable products at scale.

What You’ll be Doing:

• Ship platform capabilities across all 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
• Identify problems, ship fixes, and own outcomes like an early-stage product team

What you bring

• A minimum of five years in a professional engineering role, primarily focused on backend development, with a proven history of launching production‑ready systems.
• Expert-level systems design. You have a keen eye for the architectural foundations beneath every feature and aren’t afraid to express your technical perspective. You possess a track record of identifying and re‑engineering misaligned systems.
• Exceptional discernment for technical trade‑offs, UX, APIs, and code. You possess a clear vision of excellence across various domains and consistently elevate the standards of your colleagues.
• Demonstrated experience with agentic or LLM‑based systems beyond consumer use. You’ve shipped something where an LLM was in the critical path, built tooling that agents consume, or designed evals that catch regressions. Bonus if you can describe the failure modes you’ve seen and what you did about them.
• Initiative. Our strongest signal: you ship things nobody asked you to ship, and they turn out to matter.
• Thrives in autonomous and ambiguous environments, operating effectively without the need for a structured ticket queue.
• Excellent written communication. You’ll work across time zones (EU, US, South Africa, India) and async clarity is the highest‑leverage skill in this kind of org.

Nice to have

• Designed APIs or tools meant to be consumed by agents: structured outputs, deterministic surfaces, good observability.
• Experience within early‑stage product teams or startup environments.
• Proficiency with event‑driven architectures, monorepos, and/or observability at the platform level.

Even if you do not meet all the requirements above, we still encourage you to apply for this position. While we try to be thorough with our prerequisites, not everything about you as a candidate can be condensed into a list of bullet points. What do you have to lose?

Fountain offers an incredibly unique work environment. We employ a diverse team all over the world. Each Fountaineer is given the freedom to do their best work from wherever they choose. We also understand the importance of in‑person connections and hold in‑person meetings with your team and meet annually as an organization to build our relationships and focus on the future of moving Fountain Forward.

The benefits we offer in the United States include competitive health plans and a retirement plan. Some Fountain‑wide perks offered to all employees across the globe include a flexible vacation policy, paid holidays, monthly lunch stipends, annual allowances for ongoing education related to your profession and career advancement, along with home office, cell phone, and wellness reimbursements. Fountain is a global employer, so some benefit offerings will vary from country to country.

Fountain is proud to be an equal opportunity workplace. We welcome applicants of any educational background, gender identity and expression, sexual orientation, religion, ethnicity, age, socioeconomic status, disability, and veteran status.

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