WASM at the edge
Related service Custom software engineering
DEFINITION
Running WebAssembly modules on CDN edge nodes (Cloudflare Workers, Fastly Compute, Fermyon, wasmCloud). Stronger sandboxing, faster cold start than Node, and polyglot execution (Rust, Go, AssemblyScript, Python via Pyodide). WASI 0.2 plus the component model means modules port across runtimes. Worth it when low latency, locality and strong sandboxing all matter together. Avoid for heavy file I/O or long-lived processes.
- Firmware→
Low-level software that controls a hardware device · microcontroller, router, IoT sensor. Typical languages are C, Rust, MicroPython; OTA-updateability and signing are the critical parts.
- IoT OTA update→
Over-The-Air firmware update for IoT devices · signed image, staged rollout, rollback switch, telemetry. Lets you update a deployed fleet without physical access.
- HSM (Hardware Security Module)→
Specialised key-storage hardware · the private key never leaves the HSM, every cryptographic operation runs inside it. Foundation of banking and fintech integrations.
- OPC-UA→
Industrial communication protocol (IEC 62541) between PLCs, SCADA systems, and higher-level IT. The 2026 standard for manufacturing IT/OT integration.
- Modbus→
One of the oldest industrial protocols (since 1979) · PLCs, sensors, power meters communicate over it. TCP and RTU (serial) variants exist.
- CRDT (Conflict-free Replicated Data Type)→
Conflict-free Replicated Data Type. A data structure (counter, set, map, ordered text) that mathematically guarantees that if many peers edit it offline and sync in any order, the result is the same everywhere with no manual conflict resolution. Classic demo: the synced multiplayer cursor, where colleagues type in the same Figma or Notion document at the same time, characters do not overwrite each other, and cursors move live. Problem solved: last-write-wins and manual merge are weak primitives for collaborative editing, offline-first apps, and replicas running at the edge. Two schools: state-based (CvRDT, states can be merged) and operation-based (CmRDT, operations are commutative). In production: Yjs, Automerge, the Loro Rust library, plus Liveblocks and PartyKit as a service. The price: bigger payloads (operation logs) and you need garbage collection.
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