Job Description
Founding Software Engineer Location: San Francisco (In-Person Preferred)
Type: Full-Time | Founding Team
Stage: YC W25 | $4.1M Seed Raised
Valuation: $35M
Equity: Significant Early-Stage Ownership
About ZeroEntropy At
ZeroEntropy , we're building the
world's most accurate search engine for unstructured data - the retrieval layer powering AI agents and LLM applications. In the era of RAG (retrieval-augmented generation), search is no longer a nice-to-have - it's
the backbone of next-gen intelligence .
Our platform connects massive, complex knowledge bases to LLMs through purpose-built retrieval infrastructure. Think:
vector DB + re-ranker + agent orchestration , engineered from first principles. We're not just chaining APIs - we're rebuilding how AI systems find and reason over information.
What We're Building - A RAG-native retrieval engine with sub-second latency and high-precision recall.
- Custom-trained AI models tailored for semantic retrieval over unstructured enterprise data.
- Re-ranking algorithms tuned for multi-domain relevance and enterprise-scale accuracy.
- Real-time orchestration layers for AI agents, with low-latency, high-availability guarantees.
- Full-stack pipelines blending infra, AI research, and developer tools.
This is a chance to define a category and ship frontier systems from the ground up.
Why Join ZeroEntropy? - Greenfield opportunity: Be part of a core team inventing the future of semantic retrieval infra.
- Dual exposure: Work across low-level systems and high-leverage AI model training .
- Founder-caliber team: Collaborate with engineers obsessed with correctness, clarity, and speed.
- Massive upside: Backed by top Bay Area investors at a $35M valuation - join early, shape everything.
- Velocity over hierarchy: No bureaucracy, no politics - just world-class execution.
Ideal Background We're looking for a highly capable and product-oriented engineer who's excited to build foundational systems for AI. You might be a fit if you have:
Must-Haves: - 2+ years of full-stack engineering experience, or standout internships/projects that show equivalent skill.
- Strong fluency in React, TypeScript, Python, SQL , and backend architecture.
- A history of shipping fast and learning faster - whether in startups, side projects, or internships.
- Product intuition - you think in terms of users, not just code.
- A Top 25 CS degree or equivalent practical engineering excellence.
Bonus Points: - Built or contributed to retrieval systems, RAG pipelines, or devtools .
- Previous experience as a founding engineer, co-founder, or early technical hire .
- Internships or roles at elite companies (FAANG, infrastructure startups, AI labs).
- Passion for AI infra , LLM apps, and cutting-edge search/retrieval research.
Where We Work We're based in
San Francisco and deeply value
in-person collaboration . You'll work directly with the founders and sit across the table from other obsessive builders solving hard technical problems with speed and purpose.
Job Tags
Full time,