Senior Software Engineer I

About the role

Applications Engineering, part of CoreWeave’s Data Infrastructure organization, builds the software CoreWeave uses to plan and operate its own infrastructure business. Some of that is UNION, our data platform, where anyone in the company can query the lakehouse in plain language and stand up their own dashboards, applications, and agents. The rest is the applications behind decisions like which data centers get which hardware and when, for a company adding gigawatts of capacity a year. Engineering, finance, supply chain, and data center operations all depend on what we ship.

Responsibilities

• Build full-stack applications and features in UNION, owning them end‑to‑end in production (interface to data model).
• Work with TypeScript, React, Next.js, Python services on Kubernetes, and Postgres alongside the lakehouse.
• Develop AI‑facing natural language interfaces and agents that operate on governed data, including evaluation work to measure correctness.
• Collaborate with the people who run the processes to define what the software should do and answer for it when it breaks.
• Help shape what to build before building it, as many processes are not yet documented.

Requirements

• 5+ years building and operating production software, including both backend services and modern web frontends.
• Strong Python and TypeScript, with real experience in React, Next.js, or a comparable modern framework.
• Experience designing and running HTTP APIs that other services depend on, including timeouts, retries, and keeping writes correct when a call fails partway through.
• Strong SQL and relational data modeling, including schemas you had to change after they were already live.
• Experience shipping LLM‑backed features to production, including how you measured whether their output was correct.
• Hands‑on experience with containers and deployment tooling such as Docker, Helm, and Kubernetes, and with operating your own services.
• Experience wiring applications up to data platforms and analytical databases such as Spark, Kafka, StarRocks, or Snowflake.
• CI/CD, automated testing, observability, and on‑call for the software you own.
• Experience working directly with non‑engineers on problems nobody had specified yet, and shipping software they adopted.

Qualifications

• Experience building AI‑native applications such as text‑to‑SQL interfaces, copilots, agents, or automated insight generation.
• Experience with agent frameworks such as LangGraph, and with the tracing and evaluation tooling around them.
• Experience designing and running distributed systems in cloud‑native environments such as Kubernetes.
• Familiarity with open table formats such as Iceberg, Delta, or Hudi, and with query engines such as StarRocks, Snowflake, or BigQuery.
• Experience building internal platforms or tools that other teams used to answer their own questions.
• Background in an operationally heavy domain such as capacity planning, supply chain, or finance.

Skills

• You want the people using your software to be people you know by name, and you take it personally when it gets in their way