Mediabunny has exceeded 1 million monthly npm downloads holy shit Never expected this to happen this fast, but here we are. It's just a number at first, but it's kind of surreal when you picture what it represents. Thank you! ❤️

You can tell Claude Code is written in React because it's slow and buggy

Mediabunny v1.31.0 ships with ID3 metadata read/write support for ADTS (.aac) files, and has a more resilient MPEG-TS demuxer. 🚀

I live in crazy times where I get emails like this

When the debug videos are so good you forget you're working on Mediabunny and just start watching them

Mediabunny's now at ¾ of a million monthly downloads!!! (almost) 🎉 Time to treat myself to some malatang

Finally added this to Mediabunny: a warning if the library is bundled twice. This is almost always unintentional and leads to runtime errors, so it's good if this mistake is surfaced early. Using a symbol on the global object for the detection.

Mediabunny has world-class seeking performance across all file formats. On the left, VLC *trying* to seek through a .ts file, it just kinda gives up. On the right is Mediabunny. It just works.

I find that LLMs often struggle with writing *confident* code that fully understands all invariants at play. This code will work, but the highlighted condition is unnecessary (always evaluates to false). I always try to catch these cases to make the code tighter.

A huge milestone: Mediabunny v1.29.0 now ships with read & write support for MPEG Transport Streams! 🎉 This format is commonly used in live broadcasting. Quite proud of the implementation. It supports AVC, HEVC, AAC, MP3, O(log n) seeking, and it's very fast. HLS is next!

Mediabunny reached 5k GitHub stars!

Does anybody know if V8 (or other JS JITs) use hidden classes for common tuple types? So let's say I use a lot of [number, string, boolean], will these get optimized to a tight 16-byte struct or will these remain the slow, unoptimized array type?

B-frames are truly a mess with how out-of-order they can be; here I need to read ahead by SIX packets just to correctly compute the duration of the packet with timestamp 10.1. Very annoying! I might use the bound given by max_num_reorder_frames in the future.

Also thanks to @graham.systems for sharing mediabunny with me — I switched Anisota’s video pipeline over to it and its been so much better than ffmpegwasm so far! https://mediabunny.dev/

Been using Claude Code all day, and it has been the single best antidote against the Claude Code hype.

TypeScript is trying to type-check my MPEG Transport Stream videos hahahahaha

API learning of the day: You can use TextDecoder.decode with { stream: true } to ingest incomplete UTF-8 data in chunks!

They really said "modern" 💀

You know your algo crazy when

Took a bit after the annual Christmas download dip, but Mediabunny has now reached 600k monthly downloads! Thank you guys 🐰

Today's cool pattern: using a variable with a constant value of "undefined" to signal the intentional omission of a function argument. Instead of simply omitting the end packet argument, this code makes clear that it is intentionally not set and explains why with a comment.

Made good progress on adding an MPEG-TS demuxer to Mediabunny today! Track metadata extraction works, which is basically half the battle for this format. The spec is... extremely thicc. This feature is a requirement for the eventual HLS support in Mediabunny 👀

A sneak peak at the upcoming @mediabunny/server extension 👀 This code transcodes an H.264 .mp4 to a VP9 .webm in Node.js, fully utilizing hardware-accelerated codecs! Takes around 400 ms for a 4-second video.

There are still plenty of niche bugs in the WebCodecs API. Mediabunny uses WebCodecs and ships with dozens of workarounds for these bugs to ensure consistent behavior across browsers. Here's one example that I just added today!

Love the Chrome DevTools profiler. Made me find out about this one line that was unexpectedly making my function way slower than expected. After changing it, now it's 10x faster, and the fix took like 2 minutes. Picking these low-hanging perf fruits is usually just worth it!

Here's my talk from Demuxed two months ago! I go into the backstory of how Mediabunny came to be, and talk about the design decisions that shaped its API. This is also my first ever conference talk, and I'm very proud to have made it here😊 youtu.be/7aiUODXMuaQ

A lil sneak peak at the upcoming SampleCursor API in Mediabunny v2! It's quite the beast. It offers a single, unified API for decoding video and audio data, optimized for real-world use cases: creating video players and editors, thumbnail extraction, etc.

You know your code is god tier when ESLint pulls this (the file is syntactically valid)

My docs generator got lazy

API design can be hard, almost paralyzing at times. Any feature I add to Mediabunny now I think hard about because I won't be able to change the API anymore until v2. Maybe a more practical approach would be to label the feature as "beta" first, still allowing myself to break it.

Hit half a million monthly downloads for Mediabunny. Woah

It's a shame TypeScript's type system does not model exception types at all. Makes it super hard to predict all the ways a system could fail - you're forced to "just know" and keep it as mental state. Maybe I should explore going all "errors as values".

I'm trying to get the "Used by" section to appear for Mediabunny, but no luck. Any steps I'm missing? GitHub says I need to enable the "Dependency graph" for the repo, which I just did. Maybe need to wait a lil?

ProRes Log video file playing in Chromium with Mediabunny 👀 Spent the day playing around with this!

400k monthly Mediabunny downloads, nuts! (and 67 online Discord members)

I need to know; am I crazy for naming my tests like this?? I personally find the usual pattern "it should be able to encode aac in adts format" to be such unnecessary fluff and I don't see a good reason for naming my tests that way. Change my mind I guess?

I created a new library which polyfills the WebCodecs API in server-side environments such as Node and Bun. Full bidirectional encoding and decoding support for all codecs in the API, automatically hardware-accelerated, and super fast! Check it out! 🚀 github.com/Vanilagy/web...

The ability to inspect Node.js processes from Chrome is one of the coolest things, it's super low-friction too

Can't believe I started writing JavaScript with "var" statements and now I'm writing "for await using" loops, wtf Surely less than 1000 people in total have written this

Mediabunny has surpassed 300k monthly downloads today 😳 You guys are nuts! I always expected it to catch on, but not this quickly. We'll still need to double that number to overtake my old library mp4-muxer, so let's get to work guys!!

Just released Fragment v0.2.10 Among small fixes, I updated the canvas recorder to use mediabunny.dev by @vanilagy.bsky.social so you can now export mp4, mkv or mov files with the codec of your choice! github.com/raphaelameau...

What are good physical implementations of FIFO queues? I'm annoyed with my laundry basket because the clothes I threw in the longest time ago get washed last, so it's LIFO. I guess a "FIFO basket" would need to have two openings for it to work, which sounds awkward.

Mediabunny 1.25.0 ships with read/write support for track disposition information! 🚀 This information allows you to inspect which tracks should be preferred by a player, which are meant for hearing- or visually-impaired people, and more. Niche, but important for some uses.

Just filed 3 Chromium bug reports in 30 minutes. Practically half a Chromium dev at this point

Probably the funniest error message I've ever seen the browser throw at me. I apologize for not using 𗜀, 🐀, 𧄀, or 𮸀 as my bitrate

Mediabunny's number of Safari-specific workarounds is growing. Super dirty, but someone's gotta do it!

Had an absolutely terrific two days at Demuxed in London! Met tons of great people, and I have proudly lost my "conference speaker virginity" now 👀 Excited to share this talk once the VOD drops! Huge thanks to the Demuxed organizers for letting me have a 20-min slot. 💘

Had a blast at Demuxed day 1 yesterday! This is me (second on the left) with the Remotion folks and Konsti from Diffusion Studio!!

At the airport heading to London for two days of Demuxed! Really excited to give my talk about Mediabunny and meet a bunch of cool devs who I will to convince to use it 😊

Theo using FFmpeg to build SoraMarker is akin to using create-react-app for a new project in 2025. On the web, it's slow, unnecessarily bulky, and makes very little use of the platform. I rebuilt it using Mediabunny, and it runs 5x as fast while using 0.8% the bundle size⚡️