Watch the video, transcript and sources
+ Chrome 155 brings JPEG XL back
+ OpenAI publishes proof artifacts
+ $2 board sinks ad domainsYou probably think Google buried JPEG XL. Chrome is bringing it back, after removing experimental support, and Rust helped it get through the door. On Tuesday, October 6, Google announced JPEG XL decoding starting with Chrome 155. Today the announcement climbed Hacker News, alongside OpenAI's mathematical proof artifacts and a two-dollar board that blocks advertising domains. Chrome's earlier experiment ended in 2023. Google's explanation included insufficient ecosystem interest, which is awkward when the biggest browser controls whether the ecosystem can actually use your thing.
The new post credits persistent developer feedback, including the Interop process. The people asking for this kept asking, and Google now points to browser tests intended to make the format behave consistently. The announcement credits contributors including Helmut Januschka. Sometimes the most effective roadmap is refusing to close the issue. The biggest implementation change is a decoder called jxl-rs, written in Rust. Image decoders ingest complicated files supplied by strangers, which makes them a spectacular place to accidentally trust the internet.
Rust helps prevent classes of memory errors before they become browser vulnerabilities. Google still keeps the sandbox, and the implementation still contains small, carefully reviewed unsafe areas. Security gets layers, because reality keeps finding the seams. Google says fuzzing and AI code review found no memory safety bugs in this decoder's history. That's a useful report from the team shipping it. Future attackers are unlikely to accept the blog post as a binding contract. First question answered. Developer pressure and an optimized Rust decoder reopened the door. Google reversed a decision with engineering behind it, which is allowed even on the internet.
Now the slide-deck benchmarks. Google advertises 30–50% better compression than JPEG. Smaller downloads can help your users and bandwidth bill, but that range depends on what you encode and how you compare quality. Compression engineer Gianni Rosato published a September comparison where modern AVIF encoders beat JPEG XL across his tested fidelity range. He works on competing AVIF tools, so keep that incentive beside the graphs. These comparisons use different baselines. Beating old JPEG leaves room for AVIF to win a workload. Google itself recommends trying both formats, which is unusually practical advice for a launch announcement.
JPEG XL's other attractions include high dynamic range, lossless images and fine-grained progressive decoding. The community publishes interactive demos for exploring the format. Your audience can see a useful picture while the rest arrives. For deployment, keep a fallback image, and verify support in the browsers your customers actually run. The announcement names Chrome 155. That gives you a target version, and your analytics tell you when your audience gets there. Test your real images before changing the pipeline, and preserve the compatibility path. An image format saving bytes is useful. A migration that hides your checkout button is an expensive interpretation of minimalism.
Meanwhile, OpenAI published mathematical manuscripts and supporting proof artifacts on Tuesday. The repository contains 722 manuscripts, grouped into 372 related families. The headline count includes companion arguments and alternative proofs, so read what each paper actually claims. Many have formal proofs in Lean, which lets a computer check mathematical deductions. Others still await formalization, and OpenAI explicitly warns that some unformalized results could have issues. The repository hands researchers material they can inspect and challenge. The model remains unreleased. OpenAI says each result used roughly three hours of equivalent ChatGPT Pro thinking compute on average. That describes computational effort. It gives you neither a wall-clock guarantee nor a retail price for producing a theorem.
The release follows consultation with an independent mathematics advisory group, and includes a revision and citation process. Academia gets a new pile of homework, plus the much more useful ability to point at the exact page that needs fixing. The Lean maintainers recommend compiling small portions at a time. Even a mathematical breakthrough eventually meets the ancient enemy of software, getting the build to finish.
Finally, an open-source DNS ad blocker runs on a tiny board its creator prices at two dollars. The creator's trick is storing sorted domain hashes in flash, so the blocklist doesn't have to live in scarce working memory. This is a resurfaced project; I did not test the hardware.
The project reports roughly 50 KB of RAM use. It looks up a requested domain in the flash table, blocks a match and forwards other queries upstream. Your router can acquire a tiny bouncer with a very specific guest list. DNS filtering works at the domain level. Ads served from the same domain as useful content can slip through, and clients using another resolver can bypass it. Hash collisions can also overblock. Keep your expectations smaller than the board, which is a demanding size target.
And the detail about your existing JPEGs? JPEG XL supports lossless JPEG transcoding, with a path to reconstruct the original JPEG. That gives an old image archive a migration option without another generation of quality loss. Test the storage and delivery tradeoffs.
Verdict: SHIP IT — More choice; measure the migration
Sources
Prototype and removal discussion — Chromium Blink developers
Contemporaneous deprecation commentary — Free Software Foundation
And that's the diff for today. I'm Niko from Axrisi. Merge responsibly.
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