{"id":2985003,"url":"https://alion.io/job/castelion-lead-mission-software-engineer","title":"Lead, Mission Software Engineer","company":{"id":1795053,"name":"Castelion","domain":"castelion.com","url":"https://alion.io/company/castelion","size_band":"1001-5000","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Greenhouse","truth_index":null},"role":"Backend","role_family":"Backend","seniority":"lead","employment_type":null,"work_mode":"on_site","remote_scope":null,"remote_scope_basis":null,"remote_working_hours":null,"hiring_geo_confidence":"structured","locations":[],"countries":[],"hiring_countries":[],"hiring_countries_total":0,"salary":null,"salary_estimate":{"min_usd":139000,"max_usd":279000,"period":"year","method":"role_seniority_country_remote_cell","sample_n":1150},"experience_years_min":7,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"C++","optional":false},{"name":"CI/CD","optional":false},{"name":"Git","optional":false},{"name":"MIL-STD-1553","optional":false},{"name":"Python","optional":false},{"name":"Rust","optional":false},{"name":"Linux","optional":true},{"name":"Protobuf","optional":true}],"status":"live","first_seen_at":"2026-10-01T23:33:17Z","employer_posted_date":"2026-10-01","last_verified_at":"2026-10-22T02:20:38Z","board_verified":true,"closed_at":null,"days_open":20,"trust":{"level":"ok","repost_count":null,"flags":[],"days_open":20},"description":"Why Castelion, Why Now \nCastelion is moving incredibly fast to develop and deliver advanced defense systems at a time when execution matters more than ever. We believe focus, ownership, and excellence are decisive advantages - and we're building a world-class team to turn bold ideas into real capability. \nThis is a rare opportunity to join at an early stage, where you'll have significant ownership, collaborate with exceptional teammates, and make a direct, measurable impact on our mission and the future of the company - regardless of your function. \nLead, Mission Software Engineer\nCastelion is seeking a Lead, Mission Software Engineer to help define and build the software that connects our products into an integrated mission capability.\nMission Software spans Castelion’s full product portfolio, including weapons, launchers, command-and-control systems, sensors, mission planning tools, and external platforms. Engineers on this team build the software that allows operators and systems to plan missions, exchange targeting and sensor data, command assets, initialize and employ weapons, and execute missions end to end.\nAs a Lead Mission Software Engineer, you will own major software capabilities and technical architecture across this mission stack. You will work across product boundaries, drive interfaces between systems, and help establish the software patterns that allow Castelion’s products to operate together as a cohesive system.\nThis is a hands-on technical leadership role. You will write, review, test, and commit production code while also leading architecture, mentoring engineers, and driving complex integrations from concept through flight test and fielding.\nResponsibilities\nLead the architecture, development, integration, and deployment of mission software across weapons, launchers, C2 systems, sensors, and mission planning.\nOwn major software capabilities from early requirements and architecture through implementation, integration, test, and operational deployment.\nDevelop and integrate command-and-control software connecting operators, sensors, weapons, launchers, tactical networks, and external platforms.\nDefine software architectures, APIs, data models, and interfaces that allow Castelion products to operate together as an integrated mission system.\nDevelop software interfaces between Castelion products and aircraft, launchers, mission computers, fire-control systems, sensors, and government C2 systems.\nImplement communications across interfaces and protocols such as Ethernet, TCP/UDP, CAN, MIL-STD-1553, MIL-STD-1760, and other tactical interfaces.\nTranslate operational concepts, system requirements, and ICDs into scalable software architectures and production implementations.\nBuild tools, simulators, and test infrastructure for software-in-the-loop, hardware-in-the-loop, and system-level testing.\nLead debugging and root-cause efforts for complex issues spanning application software, embedded systems, networks, avionics, sensors, and hardware.\nWrite and review production code using modern Git-based workflows, automated testing, and continuous integration.\nEstablish strong software engineering practices around code quality, testability, interfaces, and system architecture.\nMentor software engineers and provide technical guidance across mission software efforts.\nPartner closely with flight software, avionics, guidance and navigation, vehicle engineering, test, and integration teams.\nWork directly with government customers, platform partners, operators, and external engineering teams during integration and fielding.\nSupport integration and test activities from laboratory testing through ground and flight test.\nBasic Qualifications\nBachelor's degree in Computer Science, Computer Engineering, Electrical Engineering, Aerospace Engineering, or a related technical field.\n7+ years of professional software engineering experience.\nStrong software development experience in C++, Rust, Python, Go, C, or similar languages.\nDemonstrated experience owning and delivering complex software systems or major software capabilities.\nExperience designing software architectures and interfaces across distributed or integrated systems.\nExperience contributing to and leading development in a production software codebase using Git, code review, automated testing, and CI/CD.\nStrong understanding of software architecture, APIs, networking, data serialization, concurrency, and distributed systems.\nExperience developing software that interfaces with hardware, embedded systems, or external services.\nExperience debugging complex integrated software systems across software and hardware boundaries.\nAbility to lead ambiguous technical efforts and drive them from initial definition through implementation and test.\nStrong communication skills and the ability to work across software, hardware, systems, operations, and customer teams.\nAbility to obtain and maintain a U.S. security clearance.\nPreferred Skills and Experience\nExperience developing mission planning, C2, fire control, targeting, autonomy, sensor integration, or weapon-system software.\nExperience leading software development for weapons, launchers, aircraft avionics, autonomous systems, spacecraft, robotics, or other mission-critical systems.\nExperience with MIL-STD-1553, MIL-STD-1760, UAI, CAN, Ethernet, TCP/UDP, protobuf, tactical data links, or military mission systems.\nExperience with geospatial software, coordinate systems, targeting, route planning, trajectory generation, or mission-data processing.\nExperience architecting systems that integrate sensors, shooters, operators, and command-and-control systems.\nExperience with embedded or real-time software.\nExperience developing Linux-based applications and services.\nExperience with SIL, HIL, vehicle-in-the-loop, or flight-test environments.\nExperience leading complex system-level integration and test campaigns.\nExperience mentoring and technically leading software engineering teams.\nActive Secret or Top Secret clearance.\nWhat Success Looks Like\nYou will help define the software architecture that connects Castelion’s products across the mission - from sensing and targeting through mission planning, C2, launch, and weapon employment.\nYou will own critical software capabilities, set technical direction, and ensure those systems move successfully from architecture and production code into integrated system test, flight test, and operational fielding.\nYou will also help grow the Mission Software team by raising the technical bar, mentoring engineers, and establishing the patterns that allow Castelion’s products to operate together as a complete mission system.\nCastelion offers a generous benefits package. Please refer to the bottom of our Careers page for more details. \nOther Duties \nPlease note this job description is not designed to cover or contain a comprehensive listing of activities, duties or responsibilities that are required of the employee for this job. Duties, responsibilities and activities may change at any time with or without notice. \nAdditional Eligibility Requirements \nThis position may require access to classified information or restricted U.S. Government sites, systems, or information, as determined by the Company and/or applicable U.S. Government requirements. If the position is so designated, your employment in the role may be contingent upon your ability to obtain and maintain the required U.S. Government security clearance or other government authorization, and to satisfy any citizenship or other eligibility requirements imposed by applicable law, regulation, executive order, or government contract requirements. You will be notified if and when such requirements apply. \nAffirmative Action/EEO Statement \nCastelion is an Equal Opportunity Employer. We are committed to providing equal employment opportunities to all applicants and employees without regard to race, color, religion, sex, sexual orientation, gender identity, national origin, age, disability, genetic information, protected veteran status, or any other characteristic protected by applicable federal, state, or local law. \nCastelion is committed to providing reasonable accommodations to qualified individuals with disabilities throughout the application and hiring process. If you require a reasonable accommodation to complete an application, participate in the interview process, or otherwise participate in the hiring process, please contact . Requests for accommodation will be considered on an individual basis and handled in accordance with applicable law. \nCastelion is committed to fostering a workplace where employment decisions are based on qualifications, business needs, and the ability to perform the essential functions of the role, with or without reasonable accommodation. \nEAR/ITAR Requirements \nThis position requires access to export-controlled information, and as such, employment (or hiring of a contractor) is contingent upon the candidate’s ability to access all applicable export-controlled information without additional export licensing being required by the Bureau of Industry and Security and/or the Directorate of Defense Trade Controls.","description_format":"text","description_chars":9195,"description_truncated":false,"requirements":{"experience_years_min":7,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":{"level":"bachelor","optional":false},"security_clearance":true,"languages":[]},"benefits":[],"hiring_locations":[{"name":"United States","iso":"US","kind":"country"}],"hiring_excludes":[],"relocation_offered":false,"industries":["Missiles","Defense Manufacturing"],"lifecycle":[{"event":"open","at":"2026-10-21T08:14:48Z"}],"visa":[],"liveness":{"score":72,"band":"hot","label":"Hiring now","p_open":1,"p_active":0.803,"p_room":0.9,"age_days":20,"expected_fill_days":29,"reasons":["conf:2","win:mid","comp:brand"],"computed_at":"2026-10-22T04:25:03Z"},"pay":null,"html_url":"https://alion.io/job/castelion-lead-mission-software-engineer","json_url":"https://alion.io/job/castelion-lead-mission-software-engineer.json","meta":{"generated_at":"2026-10-22T04:25:03Z","cache_seconds":300,"methodology":"https://alion.io/methodology","terms":"https://alion.io/terms","contact":"https://alion.io/contact","api":"https://alion.io/developers","about":"Alion is a live layer of people, companies and AI agents: who they are, whether they are real and active right now, what they do and how to work with them, readable by people and by agents and paid per call.","catalog":"https://alion.io/catalog.json","usage":{"tier":"crawler_verified","counted_by":"address","units_charged":1,"used_today":4748,"day_limit":null,"remaining_today":null,"minute_limit":300,"resets_at":"2026-10-23T00:00:00Z"}},"offers":[{"id":"company.slices","title":"One company in depth, by slice","status":"live","price":{"credits":0.02,"usd":0.002,"plus_per_slice":{"credits":0.05,"usd":0.005}},"unit":"per company, plus each slice with data","note":"the employer in depth","call":{"mcp_tool":"get_company","arguments":{"id":1795053},"rest":"https://alion.io/mcp/rest/get_company?id=1795053"},"human":"https://alion.io/catalog?offer=company.slices&for=job%2Fcastelion-lead-mission-software-engineer"},{"id":"market.stats","title":"A market slice: pay, demand and time to fill","status":"live","price":{"credits":1,"usd":0.1},"unit":"per slice","note":"pay, demand and time to fill for this role and place","call":{"mcp_tool":"market_stats"},"human":"https://alion.io/catalog?offer=market.stats&for=job%2Fcastelion-lead-mission-software-engineer"},{"id":"job.search","title":"Open jobs by role, technology, place, pay and visa","status":"live","price":{"credits":0.02,"usd":0.002},"unit":"per posting in a list","note":"similar open postings","call":{"mcp_tool":"search_jobs"},"human":"https://alion.io/catalog?offer=job.search&for=job%2Fcastelion-lead-mission-software-engineer"},{"id":"company.verify","title":"Is this company real and active right now","status":"pilot","price":null,"unit":"per company","request":{"url":"https://alion.io/catalog/request","method":"POST","body":"{\"offer\": \"company.verify\", \"for\": \"job/castelion-lead-mission-software-engineer\", \"note\": \"what you need it for\"}"},"human":"https://alion.io/catalog?offer=company.verify&for=job%2Fcastelion-lead-mission-software-engineer"}]}