This video demonstrates the incredibly fast incremental compilation of the Zig self-hosted compiler. By making a small, seemingly insignificant change to a source file within the compiler's codebase and rebuilding, the video showcases a rebuild time of just around 25 milliseconds. This highlights Zig's efficient build system and its focus on fast iteration times, a key advantage for developer productivity.
This YouTube clip showcases a significant improvement in the build speed of the Zig compiler through the implementation of incremental compilation. The video demonstrates a rebuild of the compiler itself after a minor code modification, specifically the addition of two characters ("++") to increment a variable. The presenter emphasizes that the entire compiler is being rebuilt, not just a single file or module. He starts a timer before initiating the rebuild command. The rebuild process, leveraging the new incremental compilation feature, completes remarkably quickly, taking just around 0.06 seconds according to the displayed timer. This speed is highlighted as a substantial advancement compared to traditional full rebuilds, which could take considerably longer. The presenter expresses enthusiasm for this achievement, emphasizing the impact on developer productivity and the iterative coding process. The video visually confirms the successful rebuild by running the newly compiled Zig compiler. The demonstration powerfully illustrates the practical benefits of incremental compilation in reducing build times and accelerating the development cycle for the Zig programming language. The video’s focus is narrowly on exhibiting the speed improvement, not explaining the technical details of the incremental compilation implementation.
Summary of Comments ( 12 )
https://news.ycombinator.com/item?id=43016944
Hacker News users generally praised the Zig compiler's fast incremental compilation demonstrated in the video. Several commenters highlighted the impressive speed and how it contributes to a positive developer experience. Some pointed out that while the demo is compelling, real-world project builds with dependencies might not be as instantaneous. Others discussed the potential of Zig's self-hosting capability and build system, comparing it favorably to other languages and build tools. A few users also expressed interest in Zig's memory management and safety features. There was some discussion about the practical limitations of incremental compilation and the importance of understanding its inner workings.
The Hacker News post titled "Incremental compilation instantly rebuilds the Zig compiler [video]" sparked a discussion with several interesting comments focusing on the impressive speed of Zig's incremental compilation, its potential, and some caveats.
Several commenters expressed awe at the demonstration in the video, highlighting how quickly the compiler rebuilds after changes. One user called it "insane" and "amazing," emphasizing how this rapid feedback loop could significantly improve developer productivity. The speed was compared favorably to other languages and build systems, with some mentioning their experiences with slower rebuild times in projects using languages like C++.
The discussion also touched on the technical aspects enabling this speed. Commenters speculated about techniques Zig might be using, such as caching and clever dependency tracking. Some discussed the benefits of Zig being self-hosted, allowing it to leverage its own compiler's efficiency for rebuilding itself. One commenter pointed out the importance of separating the "parsing/checking" phase from the "code generation" phase, potentially allowing for quick rebuilds when only the latter is needed.
A few users raised points about the video potentially being a "best-case scenario" demonstration. They questioned how well the incremental compilation would perform with larger codebases and more complex changes, suggesting real-world performance might differ. There was also some discussion about the nature of the changes made in the video and how they might be particularly suited to fast recompilation.
One commenter discussed the importance of considering the "cold" build time (initial compilation) in addition to incremental rebuilds, while acknowledging that fast incremental compilation is still a significant advantage. Another user brought up the idea of "hot reloading," where code changes are reflected instantly without even a recompilation step, wondering about its feasibility in Zig.
Finally, the discussion branched into comparing Zig with other languages like Rust and Go, discussing their respective build systems and compilation speeds. One comment mentioned the improvements in Rust's compilation times and another praised the "blazing fast" compilation of Go.