Senior Scala Software Engineer

STR • Arlington, VA

24d • Hybrid

About The Position

Senior Scala Software Engineer The Mission: Do you want to build software that solves the world's most complex national security problems? At STR, we don’t just write code; we bridge the gap between cutting-edge research and real-world mission success. You will join a multidisciplinary powerhouse of software engineers, physicists, mathematicians, and data scientists dedicated to taking innovative ideas from a whiteboard concept to a mature, deployed implementation. The Technical Frontier As part of the Knowledge Exploitation & Decisions Systems Group, you will work at the intersection of AI and human decision-making. Our portfolio is diverse and high-impact, including Command & Control (C2) via intuitive human-machine interfaces that help operators make the best possible decisions in high-pressure environments, Trusted AI & Autonomy via simulation platforms to test AI autonomy and evaluating the reliability and responsibility of autonomous systems, and Advanced Reasoning via graph-based reasoning and evolutionary algorithms for resilient workflow optimization, and enhancing language models to assess the feasibility of scientific claims.

Requirements

• BS or MS in Computer Science or a related technical field.
• 3-5+ (BS) or 1-2+ (MS) years of professional experience building maintainable, well-documented APIs and software
• U.S. Citizenship required with active DoD SECRET Clearance
• Proven proficiency in Scala or strong fluency in another typed functional language.
• You have a strong grasp of functional programming and type-driven algebraic design (immutability, pure functions, type classes, functional core/ imperative shell) and a track record of building correct, maintainable, well documented software.
• You understand or are excited to master eventual consistency, replication, and reasoning about correctness under message loss, reordering, duplication, and partition.
• You reach for property-based tests and simulation to convince yourself something is right, not just examples.
• You are an self-directed contributor who can take a high-level requirement and turn it into a working technical implementation with minimal supervision.
• You are a "trailblazer"—someone who is comfortable with ambiguity and loves learning new libraries and languages on the fly.
• We will be building foundational pieces from the group up, with rigorous testing.

Nice To Haves

• Hands on experience with CRDTs or conflict free replication (state-based, op-based or delta-state) and the join-semilattice model behind them.
• Familiarity with P2P / epidemic protocols: gossip, anti-entropy, SWIM-style failure detection, HyParView/Plumtree partial-view overlays, or Kademlia-style DHTs.
• Low-bandwidth set reconciliation and probabilistic datastructures: PinSketch/minisketch, IBLT, Merkle digests and comfort with the finite-field math underneath.
• Delay or disruption tolerant networking.
• Deterministic simulation testing and property-based testing.

Responsibilities

• Build & Scale: Design and implement flexible microservices and high-performance APIs within a robust DevSecOps ecosystem, focused on resilient distributed computing at the tactical edge.
• Drive Deployment: Take technical ownership of features within a mature mission planning solution, guiding them through the critical transition from R&D into an active user community.
• Collaborate: Work closely with other scientists, engineers, and end users to translate mission requirements into production-grade, scalable software.
• Own Your Growth: Beyond your initial project, your trajectory will be driven by the intersection of your interests and our evolving R&D portfolio.

Benefits

• STR is committed to creating a collaborative learning environment that supports deep technical understanding and recognizes the contributions and achievements of all team members.

What This Job Offers

• Job Type: Full-time
• Career Level: Senior
• Education Level: Associate degree