December 2023 Summaries

Next.js, a widely-used framework for building full-stack web applications, introduced the App Router in version 13, enhancing data fetching and reducing bundle size by leveraging React Server Components alongside the existing Pages Router, thus altering the development approach in Next.js. The guide outlines how to implement a notification workflow using Knock, focusing on identifying users, triggering workflows with the Knock Node.js SDK and Server Actions, and integrating the KnockFeedProvider with React Server Components while ensuring application security for production. Knock simplifies the creation of real-time notification feeds by managing WebSockets, messaging patterns, user preferences, presence detection, storage, logging, and frontend UI, offering out-of-the-box solutions through its in-app feed channel and customizable @knocklabs/react-notification-feed library, with the @knocklabs/client library providing a low-level SDK for custom client-side experiences. Users interested in utilizing Knock for notifications can sign up for free.

Knock, a company specializing in notification systems, successfully upgraded its Postgres database from version 11.9 to 15.3 with zero downtime by employing logical replication, support scripts, and tools from Elixir and Erlang's BEAM virtual machine. Due to the impending retirement of Postgres 11.9 by Amazon RDS, Knock prioritized an upgrade that avoided any significant downtime, as their service relies heavily on seamless operation. The process involved careful planning, risk assessment, and mitigation strategies to ensure that the large-scale migration did not disrupt service or customer experience. The approach focused on replication-based upgrades, allowing for gradual migration and testing of the new database while maintaining operational continuity. Challenges such as managing large tables, replication slots, and application-level changes were systematically addressed, culminating in a swift and smooth database transition that ensured Knock's systems remained reliable and performant for its users.