Preloop is a local, self-hosted implementation of GitHub Actions that runs existing workflows unmodified and exposes the official actions/runner protocol so the real runner can register and execute jobs unchanged. It supports the same workflow features (expressions, matrix builds, reusable workflows, concurrency groups, OIDC), can run against uncommitted or .gitignored changes, and offers a lightweight Rust runner alternative that is much smaller and uses far less peak memory. Jobs run inside hardware-isolated microVMs forked from a recorded "golden" image in about 300 ms, with elastic memory usage and a control plane that idles at very low RSS. Releases include platform binaries and CycloneDX SBOMs with checksums.
Operationally, installation can be done via Homebrew, npm, or a provided installer and a guided preloop init produces a local config and golden VM; the official runner image is large (≈9 GB compressed, ≈50 GB unpacked) so ~80 GB disk is recommended. A webhook watchdog reconciles events against the GitHub API and can open draft PRs with correct checks. Developer-focused features include DAP-powered live inspection (attach, pause, inspect job/secret/context), step-level retries, and the ability to fix code in another pane then :sync + :retry to continue without rerunning the whole workflow. Notable current limitations include Docker-action issues on Apple Silicon via Rosetta.
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Lukáš Lalinský developed zt, a type-safe HTML templating library for Zig, addressing the need for safe, fast, and HTML-like syntax in low-level web development. Inspired by JSX and Templ for Go, zt compiles templates into Zig code, enabling safe and efficient web output without runtime errors or allocations. (lalinsky.com)
AI coding agents generate more code but do not increase overall software output due to bottlenecks in human review. The review process leads to longer revisions and comments, absorbing any efficiency gains from AI tools. (arstechnica.com)
Linus Torvalds is developing a significant update to the Linux kernel using Claude Code. The project aims to enhance kernel performance and functionality. (phoronix.com)
The Reddit post discusses why the bun JavaScript runtime faces dislike among developers. It highlights concerns or issues that lead to negative perceptions of bun. (reddit.com)
TEX SIDE PREVIEW provides an Overleaf-style side-by-side LaTeX editing experience within VS Code, featuring live recompile, error highlighting, and clickable links. It supports two-way sync with Overleaf and works with local LaTeX installations on various operating systems. (marketplace.visualstudio.com)
Externalized proofs of cyclic trait implementations are incompatible with Rust's design, making modular proofs the only viable approach. Modular proofs require each implementation to explicitly demonstrate that supertrait obligations are satisfied, ensuring program correctness. (smallcultfollowing.com)
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