Engineer migrates live IoT smart cane platform to Google Cloud with zero forced app updates

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In January 2024, a backend engineer took over WeWALK, a smart cane platform serving 27,000 visually impaired users, and migrated it from a largely inaccessible self-hosted Rancher/Kubernetes cluster to Google Cloud Run, Cloud SQL, and Firestore. The core challenge was ensuring no user was ever forced to update their app, since the cane is a mobility aid and any interruption could leave someone stranded. To preserve existing AWS WebSocket endpoints baked into older client binaries, the engineer built a Lambda-to-Cloud-Run proxy that silently forwarded traffic to the new infrastructure without clients noticing the change. The migration also involved reconciling heterogeneous data stores — MongoDB, PostgreSQL, and Firestore — while handling a continuous stream of 102-byte device diagnostics arriving every ten seconds from canes in the field. The entire cutover was completed with no reported support tickets related to the migration.

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