ML/AI Research Engineer — Agentic AI Lab (Founding Team)
Fabrion· Engineering
San Francisco Bay AreaFull-timePosted 11mo ago
About the role
ML/AI Research Engineer to design, train, evaluate, and optimize agent-native AI models at the Agentic AI Lab founding team. Focus areas include LLMs, vector search, graph reasoning, and reinforcement learning to build an enterprise data-driven intelligence layer with RAG, knowledge graphs, and multi-tenant governance.
Responsibilities
- Fine-tune and evaluate open-source LLMs (e.g. LLaMA 3, Mistral, Falcon, Mixtral) for enterprise use cases with both structured and unstructured data
- Build and optimize RAG pipelines using LangChain, LangGraph, LlamaIndex, or Dust — integrated with vector DBs and internal knowledge graph
- Train agent architectures (ReAct, AutoGPT, BabyAGI, OpenAgents) using enterprise task data
- Develop embedding-based memory and retrieval chains with token-efficient chunking strategies
- Create reinforcement learning pipelines to optimize agent behaviors (e.g. RLHF, DPO, PPO)
- Establish scalable evaluation harnesses for LLM and agent performance, including synthetic evals, trace capture, and explainability tools
- Contribute to model observability, drift detection, error classification, and alignment
- Optimize inference latency and GPU resource utilization across cloud and on-prem environments
Qualifications
- Deep experience fine-tuning open-source LLMs using HuggingFace Transformers, DeepSpeed, vLLM, FSDP, LoRA/QLoRA
- Worked with both base and instruction-tuned models; familiar with SFT, RLHF, DPO pipelines
- Comfortable building and maintaining custom training datasets, filters, and eval splits
- Understand tradeoffs in batch size, token window, optimizer, precision (FP16, bfloat16), and quantization
- Experience building enterprise-grade RAG pipelines integrated with real-time or contextual data
- Familiar with LangChain, LangGraph, LlamaIndex, and open-source vector DBs (Weaviate, Qdrant, FAISS)
- Experience grounding models with structured data (SQL, graph, metadata) + unstructured sources
- Bonus: Worked with Neo4j, Puppygraph, RDF, OWL, or other semantic modeling systems
- Experience training or customizing agent frameworks with multi-step reasoning and memory
- Understand common agent loop patterns (Plan→Act→Reflect), memory recall, and tools
- Familiar with self-correction, multi-agent communication, and agent ops logging
- Strong background in token cost optimization, chunking strategies, reranking, compression, and retrieval latency tuning
- Experience running models under quantized (int4/int8) or multi-GPU settings with inference tuning
Skills
Required:Fine-tuning open-source LLMsRAG pipelinesAgent architecturesMemory and retrieval optimizationReinforcement learning pipelinesEvaluation harnessesInference optimization
Benefits
- Competitive salary + meaningful equity (founding tier)
Last updated Sep 9, 2026. Interested? Apply on the company site.
About Fabrion
AI-native platform purpose-built for the new industrial era
AI-native platform purpose-built for the new industrial era
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