AI Engineer

Twenty is seeking a mid-level AI Engineer for an in-office position in its Arlington, VA office to help build the next generation of cyber technologies that protect democracies worldwide. We're looking for someone with 4+ years of experience in developing and supporting ML and AI applications. In this role, you'll build, tune, and deploy language models that enhance our mission-critical cyber capabilities. You'll create and curate specialized datasets, fine-tune models for specific use cases, and implement efficient retrieval systems to augment AI reasoning. You'll join a world-class product and engineering team that delivers mission-critical solutions for U. S. national security, working in both cloud and on-premises environments to build AI systems that operate at machine speed. If you're passionate about applying cutting-edge AI techniques to solve complex technical challenges while making a direct impact on national security, we want to talk to you. About the CompanyAt Twenty, we're taking on one of the most critical challenges of our time: ensuring democracies prevail in the digital age. We develop revolutionary technologies that operate at the intersection of cyber and electromagnetic domains, where the speed and complexity of operations exceeds human cognition. Our team doesn't just solve problems – we deliver game-changing outcomes that directly improve national security. We're pragmatic optimists who know that while our mission of defending America and its allies is challenging, we can succeed. Role DetailsCreate, clean, and maintain high-quality training and evaluation datasetsFine-tune language models ranging from small specialized models to medium foundation modelsDevelop and optimize model serving infrastructure for production environmentsDevelop retrieval-augmented generation (RAG) systems to enhance LLM capabilities with external knowledgeImplement prompt engineering strategies to optimize model outputs for specific applicationsIntegrate AI capabilities into applications using frameworks like LangChain and CrewAIDesign and implement evaluation frameworks to measure model performanceCollaborate with cross-functional teams to identify use cases where AI can add business valueCreate technical documentation for AI systems and processesQualificationsTechnical Skills & Experience4+ years of professional software development experience with full-stack applications utilizing ML or AIStrong skills in Python and deep learning frameworks (PyTorch, TensorFlow, or JAX)Proficiency in LLM fine-tuning techniques (PEFT, LoRA, QLoRA)Proficiency in vector and graph databasesKnowledge of dataset curation, cleaning, and preprocessing methodologiesFamiliarity with model evaluation metrics and testing proceduresExperience with AI orchestration frameworks like LangChain or CrewAIEducationBachelor's degree in Computer Science, Software Engineering, or related fields, or equivalent practical experienceSecurity RequirementsMust be eligible to obtain and maintain a U. S. Government security clearanceDistinguishing QualificationsPrevious experience deploying models to production environmentsUnderstanding of prompt engineering and model alignment techniquesExperience with distributed training systemsKnowledge of model quantization and optimization techniquesAdditional SkillsMachine learning operations (MLOps)Vector databases (Pinecone, Milvus, Weaviate)Model serving technologies (vLLM, TensorRT, ONNX)Containerization and orchestration (Docker, Kubernetes)Experimentation tracking and version control for MLCloud platforms (AWS, GCP, or Azure) Apply to this Job