Blackbird
Senior Fullstack Engineer, Product
$180K–$220K
New York · On-site · Senior · Full-time · Posted Feb 12, 2026
- Experience
- 5+ years shipping production software, owning features end to end.
About the job
Own and build Blackbird’s diner-facing chat and AI agent product, from user experience and retrieval to backend runtime, evaluation, and reliability.
What you'll do
- Build the chat experience and own the agent runtime end to end, including tools and tests.
- Improve retrieval and measure answer quality through evals, tracing, and user feedback.
- Ship product improvements with product and design, keeping interactions fast, affordable, and reliable.
What they ask for
- 5+ years shipping production software and owning features end to end.
- Experience debugging across the stack, including streaming clients, application code, SQL, and service boundaries.
- Depth in LLM application development, including tool calling, context management, retrieval, and streaming.
- Strong React and TypeScript, fluency in Python, and willingness to work in Kotlin/Spring; solid Postgres and data modeling skills.
Nice to have
- Agent evaluation or LLM observability tooling such as Langfuse, Braintrust, or LangSmith; vector or geospatial search with pgvector or PostGIS.
- Experience shipping AI to native mobile, working with frontier model APIs, or in recommendations-related domains.
Pay
$180,000-$220,000 USD (annual base salary)
Tools
React, TypeScript, Python, Kotlin/Spring, Postgres, Langfuse, Braintrust, LangSmith
AI focus
Build and improve an LLM-powered diner-facing agent, including tool calling, retrieval, evaluation, observability, and task completion.
Model-written summary · the original posting is authoritative