Backend Software Engineer, (Mid-Level)

Job Description

Digital Global Systems is seeking a Backend Software Engineer to own and evolve the Target Tracker service within the CLEARSITE™ platform. This role is responsible for persistent target identity, association logic, decoder integration, and migration of legacy tracking systems to a modern, scalable backend architecture.

The engineer will build low-latency services that maintain continuous target tracking across sessions, protocols, and observation gaps using decoded identifiers and RF fingerprint matching.

Key Responsibilities

• Design and implement the Target Tracker Service, including:
  • Dual-path association using decoded identifiers (Wi-Fi MAC, BLE) and RF fingerprint similarity
  • Track lifecycle management (candidate, active, timeout, split/merge)
• Build and maintain REST APIs with strict latency SLOs (sub-20ms update paths)
• Implement persistent storage using MySQL and long-term archival in ClickHouse
• Develop composite fingerprint matching algorithms with policy-weighted similarity scoring
• Lead legacy system migration efforts, including dual-write, backfill, cutover, and rollback
• Integrate tracking services with signal processors, decoders, and image-based detectors
• Support onboarding of new protocol decoders (Wi-Fi, BLE, LoRa, LTE)
• Maintain high-quality test coverage and performance validation

Required Qualifications

• 3+ years backend development experience (Python, FastAPI)
• Strong relational database expertise (MySQL, schema design, indexing)
• Experience building low-latency REST APIs
• Familiarity with data migration strategies and real-time pipelines
• Solid testing practices (pytest, integration, performance)

Preferred Qualifications

• Experience with ClickHouse or columnar databases
• Background in entity resolution, tracking systems, or identity matching
• Familiarity with RF signal metadata or protocol decoding
• Experience with production legacy system migrations