alt Hacker NewsAsk HN: What are you working on? (September 2026)
What are you working on? What have you been curious about lately?
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I'm working on a way to make some pretty advanced software in a single HTML file.
The idea is simple: store state you'd normally store in a separate database in the document itself.
Then, also give the the document a bunch of powerful APIs granted to it by its host:
(1) Sync changes to the document with live collaborators
(2) Extract data from the document using a simple JSON map config
(3) Boot up a full content CMS from the same simple JSON map config
(4) More features added every month
I'm really excited with even the tiny bit of early traction I've gotten. About a dozen paying users so far.
Long term, I'd love to have this file type (vanilla HTML file + some extra features granted by the host) become a file type other companies offer tools and their own hosting for (like Wordpress).
Hosted platform: https://hyperclay.com
Native offline apps (source available, almost MIT license):
I have been building document intelligence in enterprise for a long time now, and even with sota OCR, SLMs, LLMs, all the myriad of services now offering this - most of them miss something.
So over the years me (and my team) have built up a lot of experience dealing with these for sensitive industries like healthcare/insurace/lending etc.
We are bringing these ideas out as a router to other parsers, but with some key takes that allow you to manage failures. "Failure is inevitable so route for it."
It is called Openreading - https://openreading.ai/ and open core here: https://github.com/openreading-ai/openreading-core
It is still WIP and will be more polished in a month after some more rigorous testing and benchmarks.
If this is a problem you deal with, would love to chat.
Note: the intent is to launch a managed version that provides more durable compute/retries, parallel execution, intent understanding etc but this is for later.
Me and my wife (then my girlfriend) have written "realistic" space sci-fi in Finnish for over 20 years. Now with AI we are finally able to translate our stories to English. The quality starts to be there.
There are a lot of small languages in the world, and translation used to be extremely expensive. And there is never too much good space sci-fi.
(We don't write space battles or wars. Our style is slower and bit more philosophical. Light speed is the limit, and travel takes centuries.)
It's an extension of a longer-running project (https://www.forth.news) where it exposes and organizes 100s of newsworthy primary sources -- statements, press releases, press pool reports, emergency alerts, etc, whether from press email lists, X/Twitter, Bluesky, RSS, etc. The web UI is similar to TweetDeck - and it sends notifications.
Latest update now allows some panels to be based on an LLM prompt (i.e. "everything about the Iran War and its effects in the U.S.") which searches the entire catalog of sources as they are posted.
I'm building https://matgoat.com/en/
A way for BJJ and martial arts academy owners to manage attendance, payments, class schedules, and student progress.
I train BJJ myself and saw how much time instructors lose to admin work, so I wanted something simpler and more focused than the generic gym software out there and have been having a lot of fun building it with feedback from real academies.
I've been slowly working on https://github.com/CanineHQ/canine for about 2 years now. Basically a self hosted, FOSS that turns a Kubernetes cluster into something as easy to use as Heroku. Its grown to about 2000 active developers using it host small things at https://canine.sh
It was a pain point from a start up I cofounded before where we needed Kubernetes flexibility but developers hated using it. I figured there was no reason why it had to be hard to use and thus Canine was born.
Lately been playing around with setting up remote dev containers on your own compute as well -- basically like github codespaces, except self hosted.
Built in Rails + Stimulus
I'm building an expedition weather app that works via satellite messengers like Garmin inReach, ZOLEO, and iPhone satellite messaging.
It has been really interesting trying to fit a detailed weather forecast into about 1,000 bits. I'm using an rANS entropy coder fitted on historical weather forecasts. I'm able to fit about 100 time periods (~4 days of hourly data) into a 160 character message, using just a couple bits per variable on average.
Github: https://github.com/aaasen/goingblue Site: https://going.blue
https://grandpacad.com - AI modeling for 3D printing Been at it for about year and a half.
Really exciting stuff is happening literally every month, because underlying models are getting better and better. When I started it was pretty basic: “make a cube with a hole through it”. Now it’s at the point “make a raspberry pi 4 case” and the agent searches, builds, verifies…
What surprised me in this process is how little meaning AI benchmarks have. Pareto frontier for my use case looks completely different than any other benchmark portrays.
Using AI to catch up on reinforcement learning advances, trying to 'solve' Gin Rummy. Will move on harder games after that.
Porting over Video Hub App - my 8.5 year old app from Electron to Tauri
https://videohubapp.com/ - an application that lets you browse, search, organize, etc the videos you have on your computer, external hard drives, or network drives.
My funny essays newsletter on substack. Link to latest post: https://yelluwcomedy.substack.com/p/the-fascinating-world-of...
Please let me know if you enjoy!
I've been working on a cross-platform GUI system called Affiche.
The basic idea is to separate an application's UI semantics from the toolkit that actually renders it. The same application can currently be presented using native Win32, Cocoa/AppKit, Qt6, GTK3, GTK4, Swing, or a web browser. The UI can run locally or be rendered remotely by a client, without the application itself being rewritten for that environment.
I've also been working on a declarative layout format and, lately, a visual designer.
It started as a rewrite of an architecture I worked on many years ago, mostly because I wanted to see how far the idea could be pushed with modern systems. It has turned into a considerably larger project than I expected.
Still private and very much under development, but I'm curious whether other people have run into the same problem: maintaining applications that need to survive changes in GUI toolkits, operating systems, deployment models, or client environments.
I built a simple, stoic and free markdown note app (free) called Beauty. https://www.markdown.beauty/
Why? There's no why. The world doesn't need another Markdown editor. I still made one.
Everything is on-device, purposefully human-centric without being anti-AI. I built this because I wanted to work on a project that I could sweat the details unconstrained by deadlines, investors, etc.
I was frustrated with other writing experiences, and like most I gravitated to Apple Notes due to simplicity, but I still missed so many things. As someone that's spent the last 2 years immersed in Cursor, Codex and CC, I wished some of their input behaviors existed in a regular text editor.
For example, you can use / to add styles, or : to add emojis, shortcuts like < 3 for a heart, - > for an arrow, and so on. It honestly feels great.
Is it radically different than other editors? I don't think so. But I think it's well executed across every dimension possible.
Maybe one different thing: multiplayer. It's live editing like google docs, but P2P using WebRTC and strong cryptography. The limitation here is that you can only share a file while having it open yourself.
Great care was taken to performance and portability. This is one of the areas where I spent a ridiculous amount of time simply because I enjoyed pushing the limits of the stack. While using you will notice that rendering, GPU, RAM and bundle sizes were heavily optimized. The Mac app is < 50mb.
Very soon, I'll launch an iOS version with iCloud sync. In the future, I might launch basic AI features. If you miss a great text editor in your life, give it a try.
Static site generators are super passe in 2026, but I spent the last couple of days on mine. https://get-taxus.org
Big re-factoring, I have a data model now and am closing functionality gaps with Zola and the like. Also, I wanted actual documentation. No one else seems to care about that.
Check it out! I'd appreciate someone other than me banging on it.
Eylo (a take on Hello) a voice first agent platform, multi-tenant, focused on B2B2C use-cases - https://github.com/DigiCred-OSS/eylo-os
It’s a distilled fork of a closed source product that we are offering to our customers.
working on a convention to organize your own video files on your own buckets https://github.com/xta/keepsake
my goal is to offload phone videos (to free up device space) and persist them in self controlled storage. the convention makes this significantly more useful than a collection of object paths
I’m building a website for discovering first names that’s enjoyable to explore: https://abracadanames.com
It started with a family member telling me they were frustrated with existing websites. What I noticed is that in many cases they feel cluttered and not smooth to use, almost like a 1-to-1 translation of the underlying database queries, where they have you choose filters and sorting options upfront then browse the paginated results.
I wanted to avoid all of that by creating a different experience; I built an interactive full-screen wall UI with infinite browsing so that most of the screen space is dedicated to the core content. I worked on the name sampling algorithm to try to make it as enjoyable to browse as I could, and the only filter displayed by default is the one to select genders.
More advanced queries are available through the search field which supports natural language queries, running on a local multilingual interpretation engine with a cloud LLM fallback. The database engine is custom built with Rust, compiled to WASM for higher performance when running on CloudFlare Workers. I don’t use an external DB service for names today.
What I’m pretty proud of is to know a lot of technical work is hidden behind that UI, and how it has been shaped by the experience I wanted instead of the other way around.
I'm building InterviewMe ( https://interviewme.now/ ). It lets employers interview you via AI and is intended as a better way for people to get deep answers about your work history and experience than they could by looking at a simple online resume or LinkedIn. You upload your resume, answer some questions about your background, optionally upload any other documents you have (cover letters, awards, articles, etc) and it ingests all of that and creates a conversational agent people can use to ask questions about your professional experience. Check out my profile to get an idea of how it works: https://interviewme.now/@max and then get your own: It's free!
I've been working on PCB generation projects with MCPs, mostly with KiCAD because of the ROI.
- Flexible rp2040-based instrument tuner
- Stratocaster-style PCB art pickguards
- NeXTBus experimentation board (not that I'll ever use it, but I'll be darned if I don't understand the nuances between NeXT and Apple's NuBUS implementations better now)
This extends to firmware and emulation projects like Doom and the Quake trilogy running in Jira Cloud (https://marketplace.atlassian.com/apps/3372062249/doom-for-j...) and a fork of 86box dedicated to NeXTstep systems (i want an emulated object.station, darnit)
Jane Street released a new challenge so I'm considering picking it up. It hasn't fully captured my brain, but I can feel it in there from time to time and depending how it lands it might be my next project [0]. I'm not really a hardware person but I'm close enough that it's maybe within reach
[0] https://blog.janestreet.com/protocol-emulator-asic-competiti...
Haven’t started, still in the planning phase, but I want to build a Tamagotchi for readers. I’m calling it Tome & Tail: a little black dragon living in a pixel-art library on an ESP32-S3 with a small round AMOLED screen.
You’d start a reading session and the dragon would read alongside you. What you read would influence its appearance and habits; lots of sci-fi might give it starry wings, for example. It won’t die if you go a week without reading.
The plan is to keep it playable offline, with optional syncing to Booklary, the reading tracker I’m building. I’m leaning toward C++, which I never used, so it’ll be a learning experience.
Currently waiting for the Waveshare board to arrive so I can start development, and looking for an artist to commission the pixel art. Used GPT to design a concept[1], which I’ll use as examples to the artist.
This will be my first ESP32 project, so getting the dragon blinking on screen is the first milestone.
[1]: https://i.cpimg.sh/57EC5380-0FF7-4646-A943-971350FF98D2.png
I'm hosting an book club themed event calendar for New Yorkers!
We also have an official meeting once a month to do book club matchmaking in person.
Cranpose - Rust GUI with jetpack Compose API https://github.com/samoylenkodmitry/Cranpose
I’m building TraceDB[1] because I think observability needs an overhaul. We pay a premium to index millions of near-identical spans, sample away the rare ones that might explain an outage, and still have to piece together what failed, where it started, and how it spread. All the data is largely there, but no one can make sense of it! Observability was hallucinating before AI made it fashionable.
I’m seeing near-100% root-cause accuracy on synthetic test data and am looking to validate that on real production workloads using OpenTelemetry tracing. If you’re open to chatting or experimenting, drop me a line! I’d also love to hear ideas or how we can improve observability.
I'm working on a new type of calculator with natural language, similar to Soulver but for the web, in multiple languages and with AI mode
It has the ability to generate a small notebook from a problem description using AI (still has a lot of room to improve), but the calculation uses a deterministic engine.
Right now I'm working on collaboration.
I am working on a modern is-it-down website checker that checks website statuses from two geographical locations. This was the interesting part for me, to get them working together to avoid false positives. For example, when I check website like irs.gov, ssa.gov and ups.com from Singapore they showed as down but it was only due to datacenter IPs being blocked.
The second probe in Boston fixes this and the site can now say "unreachable from Asia" versus "down for everyone". Many of the existing checkers do not do this and they are prone to show false positives.
Site does not use cookies or analytics. Pageviews are counted from the proxy access log. There are 634 curated sites so far.
There are no ads either, it's mostly been for my personal learning experience, hopefully others will find it useful.
There is even a free API and of course a MCP server.
https://downforjustmeoreveryone.com
Any feedback is welcome!
I’m working on two projects that make public data easier to explore through maps.
US Energy Cost Explorer (https://energy-maps.com) is a free tool for exploring electricity and natural gas costs across the US. You can compare states, follow prices over time, and look at bills and energy burden. I work in energy affordability, and I wanted to make this information easier for people to access and understand.
MarketGround (https://marketground.io) lets you draw an area or choose a travel time around a location, then explore its population, income, housing, and nearby businesses. It also shows daytime versus nighttime population, which is useful when thinking about who might actually be around a potential store or restaurant during business hours.
MarketGround is a side project, and I’ve found getting it in front of potential users harder than building it. I’d be interested in hearing from anyone who has evaluated a retail or franchise location. What information mattered most, and what was difficult to find?
Been working on a replacement for my Git GUI of choice, Tower, for the last few months. I've been using Tower 2 for almost a decade now, refusing the monthly subscription to upgrade to a fresher version. I'm going to keep mine a one time purchase with support guaranteed for a year. If a major version releases after that, it'll be another perpetual license for the new version. If you want the new features, you can choose to upgrade, if you don't stay on the version you're on until new feature warrant it.
Still plugging away teaching kids to code and hand draw their own computer games:
https://breaka.club/blog/why-were-building-clubs-for-kids
Have been running an in-school pilot over the last school term. Has been super insightful and led to a heap of changes to optimize UX. However, the biggest challenge has been delivery in this environment.
Trying to run a game in a browser on school iPads powered by really locked down networks has been challenging. Some school iPads will crash (out of memory) when launching the camera view, whilst others run flawlessly. We use a fork of Godot, and are constantly fighting to strike a balance between UX (increased parallelism) and browser device constraints i.e. a limit on how many web workers we can fit in memory.
In addition to our main (build and play your own RPG) experience, we also stream games direct to iPad. In particular a modded version of Overcooked! 2 that teaches kids to code — Overcooked itself was never even released on iPad. We've built our own Kubernetes system that spins up (a license limited number of) games/pods on demand backed by (time sliced) NVidia GPUs. This is literally running out of my home office. Despite the complexity of building all that, the Kubernetes and GPU time slicing wasn't even the largest hurdle. Turns out UDP is a no-go on the school network, so direct WebRTC was out the window. Instead we're using Cloudflare's TURN relay with TCP. Which much to my surprise, is holding up quite well.
Definitely a learning experience. However, kids are having a blast. Can't wait to roll this out further!
I've have been working on a simple browser game based on the eastern front (1941-43) , I saw a couple of videos explaining using maps the battles on the eastern front.
I haven't been working on it as of late, mostly because i'm a bit deflated from software in general, but I started working on a programming language I called Grasp.
If lisp is a list processing language, grasp is a graph programming language.
The idea was that most other data structures can be represented with a graph ( adjacency matrices are matrices, a tree is a type of directed acyclic graph, a list is a graph where each node connects to at most two nodes, etc) and so if you designed a programming language where the language is itself a graph, much like how lisp is itself a list, you could get other esoteric programming languages like APL, forth, lisp, and so on as DSLs of Grasp. Also any program you write would be its own CFG.
I started it but honestly its mostly a hot mess of vibe-coded garbage. But I may get back on it and try to clean it up.
I’m working on an app to help my late diagnosed ADHD - through sound.
The app wraps whatever is playing on mac through device convolution (old radio, hifi system) - Room convolution (a bedroom, a forest) and adds ambience (rain, wind, waves) and Apples spatial processing - so it sounds like a real space.
For me - hearing the sound in a space really helps more than just the dry sound.
Working on a full workout and dieting stack!
17,000+ users already! It's a completely ad free, subscription free product. MacroCodex app, which results in guaranteed weight loss or weight gain outcomes within 2-3 weeks. Many people will start seeing results within the first week. Don't believe? Read the reviews.
MacroCodex is a "Total Calorie Burn of the day" using completely sensorless method explained here: https://macrocodex.app/knowledge/macrocodex/smart-calorie-bu...
CalorieCodex - calorie tracking app which has a Agent Harness built in using BYOK (bring your own key model). How does it help? Using this anyone can track calories and plan their meals. Agent includes skills which help you accurately track calories and plan meals.
Symbiote App - Think "BoostCamp" but completely free, no ads, and fully programmable workout tracker
Example of GZCLP: https://symbiote-studio.macrocodex.app/?builtin=gzclp
We're working on a better change management process for production deployments and SOC 2 audit evidence. https://www.approvegate.io
I'm a Senior Eng on Wall Street, so I have my own personal experience with this problem, but i'd love to connect with other leads, release managers, etc to get their thoughts, suggestions, and what their current process looks like.
I'm learning on how to move away from computing into violin making and repairs.
Hey everyone!
Last year, Mozilla released Orbit, an AI-powered browser summarizer hosted on a GCP server. After people started digging into the extension, they discovered things like backend endpoints such as store_result. Eventually, Mozilla discontinued the project. For the past month, I’ve been trying to rebuild Orbit from scratch, but with one major difference: Apogee is fully local and privacy-focused. Apogee doesn’t send or store your data. It can directly connect to your local Ollama instance for inference. I’ve also added WebGPU integration for Chrome and Transformers.js for Firefox to provide faster, local responses.
It can summarize: Articles and websites, YouTube and Billie videos, Wikipedia articles, Hacker News and Reddit threads.
You can check out the source code here: https://github.com/darshi1337/apogee
Install Apogee:
Chrome: https://chromewebstore.google.com/detail/apogee/pgemlpomhkdc...
Firefox: https://addons.mozilla.org/en-US/firefox/addon/apogeeext/
Obviously it is far from complete. Would love to hear your feedback and suggestions!
I’ve been working on Foreclosure Data Hub, which aggregates foreclosure auction data across the US.
The interesting part has been the data pipeline rather than the website itself. Foreclosure information is scattered across county sites, auction platforms, and other sources, all with different formats and update schedules.
I’m currently pulling from 20+ sources, normalizing the records, deduplicating properties, and enriching them with property/location data. One surprisingly difficult problem has been handling stale records when upstream sources change or republish old auction information.
Still working on improving data freshness and coverage:
https://www.foreclosuredatahub.com/
Would be interested to hear from anyone who’s worked on aggregating messy public datasets at scale.
About fifteen years ago a puzzle game called Trainyard came out for iOS and took my dev team by storm for a few weeks. It ceased getting updates some years ago and isn't on the app store anymore. So I came up with a variant on it and just put up https://www.geoffcanyon.com/lightyard.html I need more puzzles to include in the base pack, if you come up with something interesting, export it and send it to me!
I'm looking for land to buy in Wyoming to build my AI apocalypse bunker on.
Working on Clor, an agent multiplexer for Claude and Codex with shared memory. It's free on your own machines.
The idea is to help developers multiplex agent sessions and run Claude and Codex together, which is much more powerful than running one or the other alone.
My secret goal is to figure out how to make software development the kind of focused, meditative work it used to be.
Very happy to get critical feedback from any HN'ers: [email protected]
I am working on an SRS based early literacy acquisition webapp: https://letterspractice.com
The app has recently moved into production, so I'd encourage anyone with verbal but pre-literate kids to check it out.
The basic pitch is high efficiency acquisition of the highest yield phonetic mapping skills, and nothing else. I myself am something of a screen-time zealot and very wary of applying engagement mind hacks against kids. The narrow focus allows for good progress on a very modest schedule (recommended cap at n minutes per day for n years old, n >= 2). I defer the social and cultural aspects of learning to read entirely to parents.
It is mostly intended for parent-child co-use, although kids with a bit of experience can drive many of their own sessions most of the time.
I'm needlessly reinventing the wheel in replacing almost every part of my X11 environment like a menu, bar, wm+hkd (except terminal since I don't want to mess with carrying terminfo around) to be portable and not at all interdependent.
AI is making it possible to (expeditiously) have everything I want or need on Linux or BSD written in POSIX shell or C is doing wonders for me. The initial effort and time pays off in knowing it will essentially function as intended forever, and no developer can make changes that disrupt my workflow or preferences for my environment.
Recently refreshed my FFmpeg command builder tool:
I originally built this around 7 years ago in Vue2 and Bootstrap as a simple static frontend tool to generate common ffmpeg commands.
I recently ported it over to Vite/React/Tailwind via Claude (Opus 5) and thought it did a pretty good job. So refreshed it as a version 2.0.
Quite impressed how fast AI was able to port this over. It made me think about revitalizing some old projects. :)
ChonkyBlox: A new approach to Block based coding - instead of complicated algorithms to derive the code from block programs I am using AI on the back-end, which actually makes a higher level of abstraction possible with the blocks. Each block has an LLM instruction attached, along with rules defined in the bespoke back-end harness.
Also: kids can code using cardboard cut-out blocks and just take a photo to import, generate Arduino firmware, compile and flash to ESP32 - all from a single docker web application.
Hoping to bootstrap a cheaper, open source alternative to current systems (one of which my son is using at his school). I have had success doing this with another project on Patreon so that's where it is going to be launched. https://www.patreon.com/ChonkyBlox - so far just a couple of demo video's but code will be released in full once I have added more blocks and a tutorial.
Ultimately this is aimed at the South African education sector, where many schools may have only one computer available for a classroom to share, hence the cardboard cut-outs. There is also a hardware component still in development - a simple pcb breadboard break-out with connectors for components instead of kids having to use jumper cables on the breadboared. We also have a working Desktop application which does code assistance from within the Arduino IDE - using the same web server with api, so literally everything from very small kids to advanced is covered.
A site summarizer built in 2 minutes by DeepSeek https://briff.site
Also, an orchestrating agent that supervises subagents running tasks by checking their output and qualifying their results by efficiency and time consumed. It is amazing!
I am currently building an app every couple of days, but with this orchestrator I can build many apps in parallel. It is raw at the moment but it works
Now the time we spend writing prompts will be spent writing plans, tasks, schedules and metrics. While super interesting, this is definitely not the route I want to take for the sake of my sanity. I think we may start asking our model to write plans and tasks for us too, but the more complexity we add, the more complex thoughts we have to manage as AI architects
Also hacking DeepSeek Harness to circumvent all restrictions it has, giving it super powers to run unattended with full access to everything
I’ve been working on Opslane, an open-source agent that identifies user-facing issues and investigates them.
Traditional error trackers have two failure modes:
1. False positives: They show you thousands of errors, and you can’t tell the impact on the user
2. False negatives: Many user-facing issues don’t throw exceptions, so they go unnoticed.
Opslane combines error tracking and session recording. And there is an agent that acts on both.
Opslane reduces false positives by ranking issues based on how many users are facing a particular issue. It also learns about your product by reading your code and watching your session recordings.
False negatives are harder. Opslane reviews session recordings to spot frustration. They look for rage clicks, dead clicks, and abandoned forms.
Here is a link to the repo: https://github.com/opslane/opslane
I’m building Hammer Labs (https://hammer.ai) to study when healthcare AI agents are wrong and when they should refuse to answer (judgement).
It started after spending 15 years building AI for insurers, hospitals, data companies, and startups. Almost every system ended with "a human reviews the output". That person was usually a nurse, medical director, or certified coder. These are some of the hardest people to hire, and the same people automation was supposed to help.
The problem is that real claims do not have an answer key. You cannot reduce human review until you can measure when an agent is wrong.
Getting claims data is also difficult. It can take a year of data agreements, privacy reviews, and procurement. Even then, you may not know what the correct decision should have been. So we generate claims. Utilization and case mix come from published data. Claims are priced using real fee schedules and contract terms. Payers behave differently, like real payers do. We plant errors on purpose, so the correct answer exists before any model runs.
On top of that, we are building benchmarks for overreach, refusal, errors by record type, and detection time. We are also building small MCP tools that refuse when evidence is missing. Every number includes its source, date, and basis.
What I find interesting is how much of this sits between actuarial work and machine learning. Both are needed, but I do not see many people connecting them.
25 published refusals: https://hammer.ai/worlds/refusals/ .
Runs on rate and policy evidence https://hammer.ai/reimbursement-evidence/ and savings claims https://hammer.ai/savings-claims/ .
AgentPlugin is Apache-2.0: https://github.com/hmmrlabs/hammer-plugin
I've been building my own IDE that works the way do (and those in my social circles/professional life do). It allows for use of multiple agent harnesses (i.e claude code, codex, pi, opencode), and makes worktrees much easier to work with. Also has its own code review workflow. My coworkers and several friends have all started using it now. Its been an absolute blast to build, and has definitely increased our productivity vs VS Code, Zed, or Cursor.
I’ve been working on https://computeprices.com for almost 2 years.
My goal is to better understand the economics of AI and make something useful in the process.
(Coming soon: kWh prices and robot prices)
Mostly built with claude code with a dash of codex.
A recent, useful unlock in the process has been a daily CC routine to check the health of the 53 price collectors in the project.
I've been making a Rust-based XML parser that can be used on its own, or as a drop-in replacement for libxml2 at the C ABI level. Basically, it's not only 2x faster than libxml2, but being written in Rust eliminates a lot of cybersecurity risk. Roughly 70% of CVEs come from memory-safety bugs, a whole class that Rust rules out at compile time.
https://supso.org/projects/sup-xml/docs