{"id":1417755,"url":"https://alion.io/job/costargroup-senior-software-engineer","title":"Senior Software Engineer","company":{"id":6056,"name":"CoStar Group","domain":"costargroup.com","url":"https://alion.io/company/costargroup","size_band":"1001-5000","is_staffing_agency":false,"employer_type":"direct","is_intermediary":false,"listed_via":null,"ats_vendor":"Workday","truth_index":{"grade":"B","score":75,"open_postings":74,"ghost_share":0,"stale_share":0.986,"repost_share":0,"time_to_fill_p50_days":29,"computed_at":"2026-10-01T05:45:00Z"}},"role":"Backend","role_family":"Backend","seniority":"senior","employment_type":"full_time","work_mode":"on_site","remote_scope":null,"remote_scope_basis":null,"remote_working_hours":null,"hiring_geo_confidence":"structured","locations":["Sydney, Australia"],"countries":["AU"],"hiring_countries":[],"hiring_countries_total":0,"salary":null,"salary_estimate":{"min_usd":92000,"max_usd":186000,"period":"year","method":"role_seniority_country_cell","sample_n":9},"experience_years_min":null,"visa_sponsorship":false,"relocation_package":false,"has_equity":false,"technologies":[{"name":"AWS","optional":false},{"name":"Azure","optional":false},{"name":"C#","optional":false},{"name":"CI/CD","optional":false},{"name":"ElasticSearch","optional":false},{"name":"GCP","optional":false},{"name":"OpenSearch","optional":false},{"name":"OWASP","optional":false},{"name":"Shift-Left","optional":false},{"name":"Shift-Left Security","optional":false},{"name":"Amazon ECS","optional":true},{"name":"Amazon EKS","optional":true},{"name":"AWS Bedrock","optional":true},{"name":"AWS Lambda","optional":true},{"name":"Digital Twin","optional":true},{"name":"IAM","optional":true},{"name":"JavaScript","optional":true},{"name":"Kubernetes","optional":true},{"name":"LLM","optional":true},{"name":"Node JS","optional":true},{"name":"TypeScript","optional":true}],"status":"live","first_seen_at":"2026-08-18T00:00:00Z","employer_posted_date":"2026-08-18","last_verified_at":"2026-09-30T19:32:41Z","board_verified":true,"closed_at":null,"days_open":44,"trust":{"level":"ok","repost_count":null,"flags":[],"days_open":44},"description":"Senior Software EngineerJob Description\nThe Senior Engineer is pivotal in supporting the delivery of our Domain Strategy by driving innovation and\nensuring the development of high-quality software solutions. They are responsible for the entire lifecycle\nof medium-sized projects: engineering design, development, test, production, and deployment and\nsubsequent fixes and improvements.\nThe Search Platform squad owns Domain's search and discovery layer - services that power how millions of users find property across residential and commercial markets every day. We are responsible for the high-performance, OpenSearch-backed APIs at the heart of the Domain experience, focusing on relevance, reliability, and scale under heavy production load. As Domain's technology landscape evolves, our squad plays a key role in shaping how discovery integrates with CoStar's global platform, while continuing to own the critical-path services behind every property search on Domain.\nWhat you’ll do\nResponsible for the entire lifecycle of medium-sized projects: engineering design, development, test, production, and deployment and subsequent fixes and improvements.\nFinds solutions to unsolved, loosely-defined, highly-technical problems.\nConsistently writes, co-writes, and reviews documentation and production-ready code that is clear, concise, tested, and easily understood by others.\nProficient in multiple languages, frameworks, and tools.\nQuick and effective in identifying and resolving issues, balancing trade-offs between speed, quality, and technical debt.\nApproaches work with a security lens and actively looks for security vulnerabilities both in code and when providing code reviews.\nUnderstands the big picture and system-wide impact, aligning with and contributes to domain wide architecture, security and technology standards\nDesigns solutions with scalability and future needs in mind.\nCollaborates with Product Owners to ensure that solutions are aligned with business and customer needs.\nOptimises for performance, maintainability, and security, actively looks for security vulnerabilities both in code and when providing code reviews.\nContribute to the System Health and Tech debt backlog for their respective owned service.\nCollaborate with Lead Engineers and Tech Leads on improving process and system change.\nEssential:\nDegree in Computer Science / Software Engineering or related field\nStrong experience in C# / .NET, Elastic Search or Open Search for distributed backend services \nExperience designing software solutions for scale\nExperience with high traffic customer-facing services\nExperience working with one of the common Cloud Platforms such as AWS, Azure or GCP\nDevOps practices, CI/CD, and infrastructure-as-code\nFamiliar with Cloud Design patterns\nFamiliar with modern Application Security Practices (OWASP) \nUnderstanding of shift-left testing and how to implement it in practice \nExperience with microservices and event-driven architectures\nExperience working with Tech leads to optimise engineering practices and processes \nExperience mentoring more junior engineers\nExperience working in cross-functional teams (Product, Design and Tech) \nNice to have\nHands on experience with AWS (ECS/EKS, Bedrock, IAM, networking)\nExperience with AI-assisted engineering workflows\n Experience building production AI/LLM systems\nTypeScript / Node.js for AWS Lambda and infrastructure-as-code (CDK)\nAWS (or other Cloud Platform) Certification\nWhat’s In It For You?\nAbout Domain (part of the CoStar Group)\nDomain is a leading property technology and services marketplace that is home to one of the largest portfolios of property brands in Australia, including the Domain, Allhomes and Commercial Real Estate (CRE) platforms. In 2025, Domain became part of CoStar Group - a global leader in commercial real estate information, analytics, online marketplaces and 3D digital twin technology. We are dedicated to digitising the world’s real estate, empowering all people to discover properties, insights, and connections that improve their businesses and lives.\nEquity, Diversity & Inclusion\nDomain is enthusiastically and unapologetically committed to fostering an equitable, inclusive work culture which reflects our customers and communities. We are proactively looking for candidates from all lived experiences, including people with disability, and people of all ages, ethnicities, cultures (including Aboriginal and Torres Strait Islander Peoples), faiths, sexual orientations, and gender identities (including trans and non-binary people).\nWe are committed to providing an equitable recruitment process for people with disability. If you require adjustments during the process we’re here to support. If you wish to receive this job advertisement in an accessible format, or have a confidential chat about workplace adjustments, please contact our Equity, Diversity and Inclusion team at  or leave a message on 1300 858 356 and we will get back to you.\nCoStar Group is an Equal Employment Opportunity Employer; we maintain a drug-free workplace and perform pre-employment substance abuse testing","description_format":"text","description_chars":5125,"description_truncated":false,"requirements":{"experience_years_min":null,"management_years_min":null,"team_size_min":null,"manages_managers":false,"education":{"level":"bachelor","optional":false},"security_clearance":false,"languages":[]},"benefits":["Equity"],"hiring_locations":[],"hiring_excludes":[],"relocation_offered":false,"industries":["Professional Services","Commercial Real Estate","E-learning","Virtual Events"],"lifecycle":[{"event":"open","at":"2026-09-28T21:22:20Z"}],"liveness":{"score":11,"band":"cold","label":"Long shot","p_open":1,"p_active":0.295,"p_room":0.36,"age_days":44,"expected_fill_days":29,"reasons":["conf:10","stale_co","evergreen","velocity","win:tail","crowd:brand"],"computed_at":"2026-10-01T05:45:00Z"},"pay":null,"html_url":"https://alion.io/job/costargroup-senior-software-engineer","json_url":"https://alion.io/job/costargroup-senior-software-engineer.json","meta":{"generated_at":"2026-10-01T10:40:33Z","cache_seconds":300,"methodology":"https://alion.io/methodology","terms":"https://alion.io/terms","contact":"https://alion.io/contact","api":"https://alion.io/developers","usage":{"tier":"crawler","counted_by":"address","units_charged":1,"used_today":1817,"day_limit":5000,"remaining_today":3183,"minute_limit":60,"resets_at":"2026-10-02T00:00:00Z"}}}