Platform Software Engineer

We are looking for a Platform Software Engineer to build the edge software that receives, authenticates and manages IoT traffic: a customised open-source LoRaWAN network server, device registry and join services, event pipelines and resilient relay services.

Key responsibilities

• Customise an open-source LoRaWAN network server (for example ChirpStack): message-processing pipeline, de-duplication, integrity and frame-counter checks, join handling, device profiles and regional configuration.
• Extend it for new device and radio capabilities, and keep the fork maintainable: upstream rebases, a patch queue and regression tests.
• Build event pipelines over MQTT with durable queues, idempotent handling and the outbox pattern.
• Use SQLite (WAL, durability and integrity settings) and PostgreSQL appropriately, and Redis or Valkey where needed.
• Design store-and-forward relays that retry safely and never duplicate.
• Meet tight memory and CPU budgets.
• Design gRPC and REST APIs with protobuf and OpenAPI, including schema evolution.
• Implement mutual TLS, role-based access and audit trails.
• Build a device registry with signed, versioned device lists, and key custody through encrypted keystores or HSM/PKCS#11, with an offline PKI.
• Cross-compile for aarch64, armv7 and x86_64, and ship both as containers and as plain packages.
• Make builds reproducible and offline-capable, produce an SBOM, and scan licences (for example with cargo-deny).
• Add observability: structured logs, metrics and tracing (OpenTelemetry, Prometheus).
• Build device and gateway simulators, property-based and fuzz tests, load and soak tests, and fault injection (power loss, link loss, clock jumps, full disk).

Requirements

• BE/B.Tech/M.Tech in Computer Science, Electronics or a related field.
• 4–5+ years of backend or systems software.
• Strong in Rust or Go (or modern C++), and willing to become strong in Rust quickly.
• Languages and Systems: Rust or Go, Linux internals, async I/O, concurrency and memory behaviour.
• Messaging and Storage: MQTT (including v5), SQL, SQLite and PostgreSQL, Redis or Valkey.
• APIs and Security: gRPC and protobuf, TLS and mTLS, JWT/OIDC, secrets handling.
• Delivery: Docker and OCI images, cross-compilation, CI/CD, flame-graph profiling.
• Quality: Unit, integration, contract and fuzz testing.