WhatsApp Adds Scheduled Messaging Feature
Meta's WhatsApp is rolling out a message scheduling feature to its user base of three billion. The new capability allows users to write messages and select a future date and time for them to be sent automatically. This addition closes a functionality gap with competing messaging platforms like Telegram and Signal.
- While new to WhatsApp's main platform, message scheduling has been a feature on competitor Telegram since September 2019, where holding the 'Send' button reveals the option and it can also be used in the 'Saved Messages' chat to create reminders. - Signal's implementation offers a technical contrast; it schedules messages locally on the user's device, which must be online at the designated time for the message to be sent. If the device is offline, the message sends as soon as it reconnects. - The feature was spotted in the iOS beta version 26.7.10.72 and will include a dedicated "Scheduled Messages" section within the chat information screen for users to view, manage, or delete pending messages. Deleting a scheduled message before it's sent does not notify the recipient. - Previously, some scheduling functionality existed within the Meta ecosystem, but it was limited to the paid WhatsApp Business Platform for automated campaigns and required API integration. This new feature is free for all users. - Before this native integration, iPhone users could approximate this functionality by creating personal automations through Apple's Shortcuts app, though this required manual confirmation before sending. - Implementing scheduled messaging at WhatsApp's scale presents significant MLOps and system design challenges, including preventing single-point-of-failure, ensuring reliability, and managing database contention for billions of pending messages. - Engineering teams at companies like Turo have tackled similar problems by decoupling the job scheduler from the message sender, often using a message queue like Amazon SQS or RabbitMQ to handle the high volume of timed jobs reliably. This prevents a single failed message from blocking the entire queue. - The core engineering challenge involves managing a massive, distributed queue of timed events. Systems like Apache Kafka are built for high-throughput event streaming but don't natively support scheduled delivery, often requiring a separate scheduling service that pushes jobs to a queue at the appropriate time.
