Staff AI/ML Engineer (Large Language Model) (TS/SCI) {S}

Job Category : ENG Requisition Number : STAFF003255 Posted : February 26, 2026 Full-Time Locations Showing 1 location Stratagem Group Aurora 3855 Lewiston St Suite 250 Aurora, CO 80011, USA ARKA Group L.P. (“ARKA”) is an advanced technologies company serving the U.S. military, intelligence community, and commercial space industry delivering next‑generation solutions to support the national security space enterprise. Built on more than six decades of excellence, ARKA brings modern approaches and a culture of innovation to the challenges of today. Join the ARKA team to learn how Beyond Begins Here. Discover your next career opportunity now! Position Overview The Staff AI/ML Engineer (LLMs) will lead the development of Agentic AI capabilities and other LLM based capabilities for a multitude of mission management applications. We offer generous relocation benefits for eligible candidates. In support of work/life balance, many positions are available for a flexible schedule within the pay period. Ask us about the opportunity for flex scheduling if that’s of interest to you. Responsibilities Lead and mentor a multidisciplined team consisting of developers and researchers to implement machine learning algorithms to solve a broad set of challenges for our various customers Lead and mentor a multidisciplinary team delivering advanced AI/ML solutions Apply LLMs to complex domain‑specific problems and operational workflows Adapt and fine‑tune foundation models for specialized use cases Design and implement retrieval‑augmented generation (RAG) systems and semantic search architectures Build production‑grade LLM applications and agentic systems Deploy scalable AI solutions across cloud, on‑prem, and hybrid environments Analyze large, multi‑modal datasets to extract meaningful features and actionable insights Translate emerging research into applied, mission‑relevant capabilities Communicate technical strategy, status, and risks to internal and external leadership Required Qualifications B.S. in machine learning, computer science, mathematics, or related fields 8+ years of experience, preferably in software development or as a data scientist with 2+ years of building LLM applications using some of the following: Fine‑tuning foundational models Steering Techniques (e Sparse auto encoders, representation tuning) Building adapters to use foundational models (e.g. PEFT, llama factory) Prompt engineering techniques / Inference time techniques (e.g chain of thought, tree of thoughts, etc.) Using Retrieval Augmented Generation techniques to populate and query vector databases (e.g. Weaviate, pinecone, pgvector) Using LLM Frameworks (e.g. LangChain, DSPy, Microsoft Agent Framework) Using AI APIs ( e.g AWS Bedrock, OpenAI) Using LLM deployment frameworks (eg llama.cpp, vllm, tgi) Developing UIs with ReAct Experience leading an interdisciplinary team of researchers and software developers and working with a program manager to define project scope and schedule to ensure we meet project milestones as defined by our customers Experience with Python and data science / machine learning libraries (e.g. NumPy, Pandas, Polars, scikit‑learn, etc.) Experience contributing on a team using version control (e.g. git, GitLab, Bitbucket) Active TS/SCI U.S. Government Security Clearance Preferred Qualifications M.S. or PhD in machine learning, computer science, mathematics, or related fields Experience leading an interdisciplinary team of researchers and software developers Experience with any of the following: Large Language Models and experience identifying ways to incorporate them into new domains and applications Applying Transformer‑based architectures to domains in other areas outside of Natural Language Processing (NLP) such as computer vision Natural Language Processing algorithms such as BERT Reinforcement learning and familiarity with Gymnasium Gym, OpenEnv, TorchRL, RLlib, and Stable Baselines Applying clustering algorithms and/or deep neural networks to real life problems Implementing tracking and pattern‑of‑life algorithms Experience with GenAI Ops techniques (e.g. LLM‑as‑a‑judge) and frameworks (e.g. LangFuse, MLFlow, Arize Phoenix) Experience with Machine Learning libraries and frameworks such as HuggingFace and LangChain Experience with Linux Experience with CUDA and Python libraries such as CuPy, Numba, CuSignal, CuDF, etc. Familiarity with using AWS cloud computing resources such as EC2, S3, Lambda, etc. Experience with any of the following additional languages: Java, C++, Rust, Go, and/or C# Experience in application deployment, virtualization, and containerization (e.g. Podman, Docker, Kubernetes, Rancher) Experience shaping and writing proposals Adjudicated Counter Intelligence or Full Scope Polygraph Pay Range: $150,000 - $200,000 Your actual level and base salary will be determined on a case‑by‑case basis and may vary based on the following considerations: job‑related knowledge and skills, education, and experience. The application window will close in 60 days for this position. Location: Aurora, CO Being situated at the foot of the Rocky Mountains, Aurora provides opportunities to enjoy all the beautiful nature that Colorado has to offer, while also being a 20‑minute drive from downtown Denver and 15‑minutes to the Denver International Airport. Benefits Company contributions to qualified HSA accounts 401k retirement plan with industry leading company contributions 3 weeks of vacation accrual per year plus time off for sick leave and unscheduled life events 13 paid holidays Upfront tuition assistance for approved degree programs Annual bonus program based on company and employee performance Company paid life insurance, AD&D, Short‑Term and Long‑Term disability insurance 4 weeks paid Parental Leave Employee assistance program (EAP) This job operates in a professional office environment. While performing the duties of this job, the employee routinely is required to use hands to keyboard, communicate, listen to, and interpret instructions and remain stationary for extended periods of the time. This would require the ability to move around the campus and occasionally move/lift items weighing up to 25 lbs. Reasonable accommodations may be made to enable individuals with disabilities to perform the essential functions of the job. Applicants are invited to apply for a reasonable accommodation to perform the essential duties of the job. To apply, send a request to View email address on click.appcast.io or contact View phone number on click.appcast.io and press 2 for Human Resources. ITC & Security Clearance Requirements: This position requires an active TS/SCI U.S. Government Security Clearance. Visa Restrictions: No visa sponsorship is available for this position. Pre‑employment Screenings: Employment with any ARKA companies in the U.S. is contingent upon satisfactory completion of several pre‑employment requirements to include a credit check, background check, and drug screen. Equal Opportunity Employer/Protected Veterans/Individuals with Disabilities This employer is required to notify all applicants of their rights pursuant to federal employment laws. For further information, please review the Know Your Rights notice from the Department of Labor. #J-18808-Ljbffr CACI International