Senior Scala Software Engineer

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, andenhancing language models to assess the feasibility of scientific claims. What You’ll Do: 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. Who You Are: Education: BS or MS in Computer Science or a related technical field. Experience: 3-5+ (BS) or 1-2+ (MS) years of professional experience building maintainable, well-documented APIs and software Clearance: U.S. Citizenship required with active DoD SECRET Clearance Technical Depth: 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. Independence: You are a self-directed contributor who can take a high-level requirement and turn it into a working technical implementation with minimal supervision. Mindset: 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. Bonus Points: 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. Primary: Scala 3 (LTS) on JDK 21+, typed functional programming with `cats-core` Observability: OpenTelemetry, slf4j / logback Secondary: Python (for AI/Data integration) Logistics Location: Hybrid at one of STR’s offices in Woburn, MA or Arlington, VA Travel: Periodic travel (up to 20%). Pay Information Full-Time Salary Range: $140,000.00 to $170,000.00 The salary range listed is based on external market data. Offers are based on factors, such as but not limited to, the candidate’s experience, education, training, key skills/critical skills, security clearances, and prevailing market and business conditions. STR is a growing technology company with locations near Boston, MA, Arlington, VA, near Dayton, OH, Melbourne, FL, and Carlsbad, CA. We specialize in advanced research and development for defense, intelligence, and national security in: cyber; next generation sensors, radar, sonar, communications, and electronic warfare; and artificial intelligence algorithms and analytics to make sense of the complexity that is exploding around us. STR is committed to creating a collaborative learning environment that supports deep technical understanding and recognizes the contributions and achievements of all team members. Our work is challenging, and we go home at night knowing that we pushed the envelope of technology and made the world safer. STR is not just any company. Our people, culture, and attitude along with their unique set of skills, experiences, and perspectives put us on a trajectory to change the world. We can't do it alone, though - we need fellow trailblazers. If you are one, join our team and help to keep our society safe! Visit us at for more info. STR is an equal opportunity employer. We are fully dedicated to hiring the most qualified candidate regardless of race, color, religion, sex (including gender identity, sexual orientation and pregnancy), marital status, national origin, age, veteran status, disability, genetic information or any other characteristic protected by federal, state or local laws. If you need a reasonable accommodation for any portion of the employment process, email us at View email address on click.appcast.io and provide your contact info. Pursuant to applicable federal law and regulations, positions at STR require employees to obtain national security clearances and satisfy the requirements for compliance with export control and other applicable laws. Voluntary Self‑Identification For government reporting purposes, we ask candidates to respond to the below self‑identification survey. Completion of the form is entirely voluntary. Whatever your decision, it will not be considered in the hiring process or thereafter. Any information that you do provide will be recorded and maintained in a confidential file. As set forth in STR’s Equal Employment Opportunity policy, we do not discriminate on the basis of any protected group status under any applicable law. If you believe you belong to any of the categories of protected veterans listed below, please indicate by making the appropriate selection. As a government contractor subject to the Vietnam Era Veterans Readjustment Assistance Act (VEVRAA), we request this information in order to measure the effectiveness of the outreach and positive recruitment efforts we undertake pursuant to VEVRAA. Classification of protected categories is as follows: A "disabled veteran" is one of the following: a veteran of the U.S. military, ground, naval or air service who is entitled to compensation (or whom but for the receipt of military retired pay would be entitled to compensation) under laws administered by the Secretary of Veterans Affairs; or a person who was discharged or released from active duty because of a service‑connected disability. A "recently separated veteran" means any veteran during the three‑year period beginning on the date of such veteran's discharge or release from active duty in the U.S. military, ground, naval, or air service. An "active duty wartime or campaign badge veteran" means a veteran who served on active duty in the U.S. military, ground, naval or air service during a war, or in a campaign or expedition for which a campaign badge has been authorized under the laws administered by the Department of Defense. An "Armed forces service medal veteran" means a veteran who, while serving on active duty in the U.S. military, ground, naval or air service, participated in a United States military operation for which an Armed Forces service medal was awarded pursuant to Executive Order 12985. Voluntary Self‑Identification of Disability Form CC‑305 Page 1 of 1 OMB Control Number 1250‑0005 Expires 04/30/2026 Alcohol or other substance use disorder (not currently using drugs illegally) Autoimmune disorder, for example, lupus, fibromyalgia, rheumatoid arthritis, HIV/AIDS Blind or low vision Cancer (past or present) Cardiovascular or heart disease Celiac disease Cerebral palsy Deaf or serious difficulty hearing Diabetes Disfigurement, for example, disfigurement caused by burns, wounds, accidents, or congenital disorders Epilepsy or other seizure disorder Gastrointestinal disorders, for example, Crohn's Disease, irritable bowel syndrome Intellectual or developmental disability Mental health conditions, for example, depression, bipolar disorder, anxiety disorder, schizophrenia, PTSD Missing limbs or partially missing limbs Mobility impairment, benefiting from the use of a wheelchair, scooter, walker, leg brace(s) and/or other supports Nervous system condition, for example, migraine headaches, Parkinson’s disease, multiple sclerosis (MS) Neurodivergence, for example, attention‑deficit/hyperactivity disorder (ADHD), autism spectrum disorder, dyslexia, dyspraxia, other learning disabilities Partial or complete paralysis (any cause) Pulmonary or respiratory conditions, for example, tuberculosis, asthma, emphysema Short stature (dwarfism) Traumatic brain injury PUBLIC BURDEN STATEMENT: According to the Paperwork Reduction Act of 1995 no persons are required to respond to a collection of information unless such collection displays a valid OMB control number. This survey should take about 5 minutes to complete. #J-18808-Ljbffr STR