The Growth of the Swift Server Ecosystem

Nearly ten years ago, Swift was open sourced and an official runtime for Linux was released. I’ve been involved with Swift on the server since almost the very beginning, originally picking it up as a way to use a language I really enjoyed for backend development. In that time Swift has come a long way, with stability across platforms, a burgeoning ecosystem and many success stories. It’s matured into a great option for highly-scalable server applications, websites, and lambdas. In this post, I’ll cover how Swift:

• is seeing a number of success stories of running critical production workloads
• has evolved to be a powerful language for server development
• has a thriving ecosystem of frameworks and libraries
• has a growing and passionate community - including a dedicated server conference coming up in October!

→ swift.org/blog/swift-on-the-server-ecosystem/

This post reflects on a decade of Swift’s evolution as a robust server-side language since its open-sourcing and Linux runtime release. Highlighting success stories, it notes the Things app’s backend migration from Python to Swift, achieving a 4x performance boost and cost reduction, and Apple’s Password Monitoring Service, which saw a 40% throughput increase and 90% memory usage drop after switching from Java.

Swift’s language advancements, including UTF-8 strings, Codable, keypaths, property wrappers, and Swift Concurrency with Sendable, have eliminated data race issues, as evidenced by Vapor’s crash-free record. The ecosystem thrives with frameworks like Vapor and Hummingbird, supported by the Swift Package Index and observability packages for logging, metrics, and tracing, ensuring compatibility with tools like Prometheus.

Swift’s interoperability with C, C++, and Java, enhanced by cross-compilation SDKs and the Swiftly CLI, facilitates integration and migration. The growing community, driven by the Swift Server Workgroup, culminates in the annual ServerSide.swift conference, featuring talks on gRPC, concurrency, and success stories, with workshops for newcomers, fostering a vibrant future for Swift server development.