emath WASM playground on the way!! this is fun to mess around with! star the repo and follow me for updates to know when 0.1.0 alpha will land thank you @FactoryAI @droid for the opportunity to build something I'm so interested in

When #DuckDB-Wasm# was launched in 2021, databases could not be persisted: everything lived in the Wasm heap and vanished when the tab closed. Keeping data meant serializing tables to Parquet, storing the bytes in IndexedDB, and re-registering them on the next page load. This was doable, but had to be handled at the application layer and was not offered out of the box by DuckDB-#Wasm#. Modern browsers now ship the Origin Private File System (OPFS), a per-origin, sandboxed file system with random-access reads and writes. DuckDB-Wasm can use it as a storage backend. This post by @carlo_piovesan and @GeertjanW shows you how:

I've moved on to optimizing libghostty Wasm runtime memory usage and I am learning a lot! The first discovery: Zig's `std.heap.MemoryPool` is very bad for Wasm! We replaced it with a custom Wasm-specific pool that lowered libghostty's required terminal memory by 75% without any measurable throughput impact. Some background: `std.heap.MemoryPool` is a very high performance memory pool implementation for identically sized items directly in the Zig standard library. For non-wasm targets, its very good! We use it a lot! But there is a major problem due to the interaction of two separate behaviors: first, the Zig std memory pool grows by 1.5x whenever it has no free space. To grow, it asks the backing allocator, which is usually general-purpose. On Wasm targets, that general-purpose allocator is the BrkAllocator which grows by power-of-two for big allocation slots (what we were hitting). On native (non-wasm) targets, this just gets increasingly large virtual memory allocations, which is fine! Good, even! Virtual memory mappings are cheap and the total mapped memory isn't resident/physical until it's used. Allocation syscalls are expensive and its better to get too much. But wasm is not like that. Every linear memory growth is immediately measured, zeroed, resident memory. Second, memory growth doesn't require a "syscall" in the same sense/overhead of the word. The result is you get really big linear memory growth in WebAssembly and it looks/feels bad in web inspector and saves absolutely nothing on future IO. We replaced it with a very simple pool (~20 lines of effective code) that grows the linear memory by exactly 1 item size when it needs it and maintains a module-global free list (assumes single-threaded Wasm module) so same-item pools are shared globally. PR here:

i think the big thing people miss with WASM is the cost of serializing and deserializing across the WASM border almost always outweighs the benefits. You have to find problems that do not have this fundamental problem.

HashPort frontend verification actually has two different layers The first layer is Published The wallet takes the HTML JavaScript Worker WASM and other executable resources actually loaded by the current page and calculates their SHA-256 hashes, then compares them with the file hashes recorded by the on-chain Store Only when everything matches can the wallet confirm that the current page is identical to the version published on chain But this still does not prove that it is the official website Anyone can publish a frontend on chain, including an attacker publishing a phishing website That is why there is a second layer called Official The target contract can declare its official frontend through the Frontend Declaration Registry When the user is about to sign a transaction, the wallet can compare the Frontend Identity of the current page with the frontend declared by the contract Published proves that the files have not been secretly modified Official proves that the frontend has been recognized by the target contract These two checks solve two completely different problems

Notice of upcoming changes to CosmWasm: A new forum discussion is live asking for feedback on two Wasm updates on the Cosmos Hub: - Increase max contract size to 1.6MiB - Implement two additional Wasm gRPC queries Forum post link: