Fullstack Software Engineer (Frontend-Leaning)
Location: San Francisco, CA (FiDi) — In-office Mon–Fri, remote on Sundays
Company: AfterQuery
Website: afterquery.com
LinkedIn: AfterQuery
About AfterQuery
AfterQuery is pushing the frontier of large language models (LLMs) and AI agents through novel datasets and experimentation—building the complex infrastructure that powers frontier data creation for agentic and hard reasoning workflows. Partnered with all five leading AI labs, AfterQuery is rapidly becoming the go-to data infrastructure provider for YC-backed companies.
Founded in 2024 and backed by $3M in seed funding, the company is on a sharp hockey-stick growth trajectory with explosive demand from top-tier AI teams.
The founding team blends elite experience across quantitative trading (Citadel Securities, Jane Street), big tech (Google, Meta), and finance (Morgan Stanley, Silver Lake)—bringing a rare mix of engineering precision and business rigor. Currently a lean, talent-dense 10-person team, the majority being engineers who’ve proven they can ship at world-class speed and quality. The culture is fast-moving, collaborative, and deeply mission-driven—you’ll be building alongside peers who’ve done hard things and are now channeling that same intensity into redefining AI infrastructure.
Role Overview
AfterQuery is hiring a Fullstack Software Engineer (Frontend-Leaning) to help design, build, and scale our data infrastructure systems for LLMs and AI agents. You’ll work closely with AI researchers, build production-grade systems end-to-end, and own significant portions of our stack from day one.
Responsibilities
- Design, develop, and deploy fullstack applications and data pipelines using modern frameworks.
- Own projects end-to-end—from ideation and architecture to implementation and production.
- Collaborate directly with AI lab researchers and enterprise clients on new data and infrastructure requirements.
- Contribute to the evolution of our platform architecture, ensuring scalability, reliability, and speed.
- Rapidly iterate and ship features in a fast-paced, high-impact environment.
Requirements
Experience & Education
- 0–3 years of experience as a frontend-leaning fullstack engineer.
- Undergraduate degree completed in the U.S., preferably from an Ivy League or top computer science program.
- DevOps experience (CI/CD, container orchestration, cloud infrastructure).
Technical Skills
- Fullstack capability across Next.js / React , Node.js / Python , and Kubernetes .
- Experience with Kafka , Redis , and Elasticsearch .
Soft Skills
- Proven ability to build and ship products end-to-end with strong ownership.
- Track record of fast iteration and delivering under ambiguity.
- Comfortable being client-facing and collaborating with AI researchers.
Why Join AfterQuery
- Work on the frontier of AI infrastructure with world-class partners.
- Join a tight-knit, elite team that values speed, craftsmanship, and ownership.
- Build systems that power the next generation of intelligent agents.
- Competitive compensation and early-stage equity.