Retail POS systems require continuous operation even during internet outages, and Couchbase offers solutions to facilitate this through its various approaches, ensuring that sales processes are uninterrupted and data can be synced afterward. Couchbase Lite can be embedded in each terminal, allowing them to operate independently with local data and sync once online, though this may lead to data divergence until synchronization occurs. Alternatively, a peer-to-peer sync between devices can keep data consistent locally without a central server, suitable for smaller setups but not ideal for larger store networks. For bigger deployments, a Couchbase Edge Server acts as a local hub, maintaining a shared state among devices and reducing WAN load by managing upstream syncs. Retailers often adopt a hybrid model, combining these methods to balance resilience, real-time consistency, and efficient syncing to the cloud through Couchbase Capella.