Software Engineer

LB88
  • -
  • San Francisco, CA
  • Permanent

๐Ÿšจ Software Engineer โ€“ Backend, Data Infrastructure & AI

๐Ÿ“ San Francisco โ€“ On-site


Iโ€™m working with one of the fastest-growing companies in AI, building the expert reasoning and data infrastructure used to develop frontier models.


They capture the step-by-step reasoning, trade-offs and judgment of nearly 100,000 verified domain experts, transforming it into high-quality training data, evaluation frameworks and agent environments for the worldโ€™s leading AI labs.


They are looking for a backend-leaning Software Engineer with strong infrastructure experience to own entire technical verticalsโ€”from data collection and pipeline architecture through cloud infrastructure, deployment and production delivery.


You'll work on:


๐Ÿ’ป Building scalable backend systems and complex data-capture workflows using Python and JavaScript/Next.js

๐Ÿ“Š Architecting high-throughput, data-heavy pipelines handling demanding production workloads

โ˜๏ธ Owning cloud infrastructure across AWS or GCP, including serverless systems and cloud functions

โš™๏ธ Deploying and operating production workloads using Kubernetes and Docker

๐Ÿ“จ Building low-latency distributed systems using Kafka or RabbitMQ, Redis and Elasticsearch

๐Ÿš€ Taking projects from an ambiguous problem through architecture, implementation, infrastructure, deployment and delivery

๐Ÿค Working directly with the founders to define product strategy, ship quickly and make important technical decisions

๐Ÿ—๏ธ Establishing engineering best practices and helping lay the foundations for the teamโ€™s continued growth


Requirements:


โœ… Strong backend, platform or infrastructure engineering experience

โœ… Hands-on production experience with Python

โœ… Experience owning substantial projects end-to-end, including their cloud infrastructure

โœ… Strong knowledge of distributed systems, data pipelines and high-throughput architectures

โœ… Production experience with Docker and ideally Kubernetes

โœ… Experience with AWS or GCP, serverless architecture and cloud-based data processing

โœ… Familiarity with technologies such as Kafka, RabbitMQ, Redis or Elasticsearch

โœ… Evidence of turning ideas into reliable production systems in a fast-moving environment

โญ Experience with AI research, LLM evaluations, human-in-the-loop systems or frontier-model data infrastructure is highly valuable


Frontend development is not the focus of this position. They are particularly interested in backend-leaning engineers, platform engineers and infrastructure specialists who can take complete ownership of data-intensive systems.


This is not a role for someone who has only contributed to a narrow component within a large engineering organisation. They are looking for a high-agency engineer who can understand an entire problem, make sound architectural decisions and remain accountable for the production outcome.


The company has raised a $30M Series A at a $300M valuation, led by Altos Ventures, with backing from The Raine Group, Y Combinator and BoxGroup. Its angel investors include researchers and executives from Google DeepMind, OpenAI, Anthropic, Meta Superintelligence Labs and Microsoft AI.


The company has already grown beyond a $100M revenue run rate, is highly profitable and serves every major frontier AI lab.


Youโ€™ll join a team of more than 30 exceptional engineers, researchers and operators with experience from Citadel Securities, Meta, Google, Silver Lake and Morgan Stanleyโ€”and help build infrastructure that directly shapes how frontier AI systems improve.


โœˆ๏ธ Visa sponsorship is available, including O-1 and H-1B transfers. Relocation support may be negotiated at offer stage.

๐Ÿ’ฐ Competitive salary and meaningful equity.

Harry Bailey Researcher

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