6 ms·
Show HN: Extend UI – open-source UI kit for modern document apps
We're open-sourcing 14 components & examples today for PDF, DOCX, and XLSX viewers, plus bounding box citations, file upload, e-signature, and more. It's MIT licensed and fully customizable.
Demo video here: https://share.extend.ai/kRmSGKRF https://share.extend.ai/kRmSGKRF
When we started, we tried every file viewer and document component library we could find. Unfortunately, none of them had all the functionality (and polish) that we wanted, so we ended up building our own for https://extend.ai/ https://extend.ai/. It was only ever meant to be internal, but enough customers kept asking for it that we decided to open source it.
It's useful for building document processing agents, real-time user facing document intake flows, or all kinds of internal tooling.
We naively thought this would be a solved problem. Turns out, making PDF/XLSX/DOCX viewers that work at scale is not trivial...we use and maintain it for Extend ourselves, so we've fixed a lot of edge cases that came up while running millions of pages / day through our own system. Our hope is that with our resources + community support, it'll keep getting better over time.
- spankalee 4mo agoThese should really be web components. Leaving out every framework other than React is really bad for the web.
- andrewlu0 4mo agothats fair and definitely something we can try supporting in the future. we started with React because of how familiar models are with shadcn and tailwind we hope this can be useful for people building in React though!
- digitaltrees 4mo agoThen build it yourself. They do work for free, give it to the world, and your response is: do it differently the way I want.
- ranger_danger 4mo agolet's all try to be nicer
- digitaltrees 4mo agoI agree, but your comment should be directed at the same poster mine was not me
- warthog 4mo agoreally like these - curious how the xlsx editor and viewer is built in that what kind of headless spreadsheet? could not have been easy
- andrewlu0 4mo agoHi! I'm one of the engineers at Extend that worked on this - one of our other engineers created a Rust XLSX/XLS parser that we ported to WASM to our @extend-ai/react-xlsx package which handles the rendering/charts. It exposes some hooks so users can use their own components for the toolbar
- drivingmenuts 4mo agoHow much was actual engineering and how much was telling an AI what to do?
- deleted 4mo ago[deleted]
- dvt 4mo agoEven if it was just prompting, not sure how that takes away from the final, fairly polished, product. How do you define "actual engineering"?
- lateforwork 4mo ago[dead]
- CraigJPerry 4mo agoThose bounding box demos are decent. By quirk of fate i've spent the past 2 days prototyping some stuff on pdfjs. Just trying to figure out a game plan for handling bounding boxes in the face of page zooming, different resolutions etc. etc. I can't see it mentioned whether the components are virtualising pages (as in reusing dom elements as document pages scroll by). I guess i just learned what i'll be exploring tomorrow then...
- andrewlu0 4mo agoyes - the pdf/docx viewer use react-virtual to virtualize the pages the zoom should work with the bounding box highlights, we're working on adding rotation support
- KolmogorovComp 4mo ago> This page could not load On mobile Safari…
- andrewlu0 4mo agohm seems to look ok on mine - is this on the root page?
- egeozcan 4mo agoWhy doesn't it mention anywhere that they are React components?
- andrewlu0 4mo agowe'll try to make it more clear on the landing/introduction page!
- hju22_-3 4mo ago_Try_ to? Are you serious? We're not taking ambiguity due to phrasing, we're talking straight up not mentioning it on either the front page, on the show all page or even on the page the components button takes you to. Not even on this forum thread. There's barely any text on the front page to change and there are even multiple places you can mention React. You could mention it in the title, e.g. "Open source _React_ UI kit for modern document apps" or you could add it to the second paragraph, e.g. "React components ready to drop into user-facing flows, agents, or internal tools." Not to mention the components page. And given what you use to make the website, how does it take this long to update something this trivial when you are going out of your way to promote it, replying to comments and your other services by proxy? Also, add either user interactive loading of components or lazy load the demos, the amount of demos murder performance on phones.
- andrewlu0 4mo agocoming back to this now and added it in a few places on the demos - everything below the fold is lazy loaded but i will see what we can do to improve the mobile perf
- digitaltrees 4mo agoTone.
- resurge 4mo agoNot just React, but it apparently also depends on Next.js Dependency in package.json: - https://github.com/extend-hq/ui/blob/main/apps/v4/package.json https://github.com/extend-hq/ui/blob/main/apps/v4/package.js... Dependencies in some components: - https://github.com/extend-hq/ui/blob/main/apps/v4/components/command-menu.tsx https://github.com/extend-hq/ui/blob/main/apps/v4/components... - https://github.com/extend-hq/ui/blob/main/apps/v4/components/docs-sidebar.tsx https://github.com/extend-hq/ui/blob/main/apps/v4/components...
- hobofan 4mo agoThanks, that looks awesome! We were looking to add DOCX and XLSX preview to our app, and were planning to do server-side conversion to PDF (which seems to be what most other apps resort to) due to the lack of good libraries to render it, and this is exactly what we were looking for! :)
- andrewlu0 4mo agothanks! would love to get your feedback i can't promise its visually 1:1 with Word/Excel but its pretty close on the corpus we tested with
- dvt 4mo agoSuper cool. Working on a local AI tool specifically for document workflow automation (where context = screen/web/folders/files), and this could come in super useful. I do most of the PDF/DOCX/etc. parsing natively in Rust, but having a nice way to see the output without spinning up Word or Powerpoint is a huge leap. Thanks for releasing publicly.
- andrewlu0 4mo agonice - did you write a custom parser for PDF/DOCX? we wrote one for XLSX after running into event loop issues with sheet JS
- dvt 4mo agoUsing lopdf[1] for PDF parsing, rtf-parser[2] for RTF, calamine[3] for XLSX, and I'm sure you know that DOCX/PPTX/etc. is basically just a zip file of XML + text. The LLM cares about textual data (which just gets moderately cleaned up post-extraction), so I (thankfully) didn't have to deal with rendering. But showing a preview or end-result to a user would be a huge plus, so I can see myself using your library. [1] https://github.com/J-F-Liu/lopdf https://github.com/J-F-Liu/lopdf [2] https://github.com/d0rianb/rtf-parser https://github.com/d0rianb/rtf-parser [3] https://github.com/tafia/calamine https://github.com/tafia/calamine
- stinger 4mo agoDoes it/will it support Markdown files?
- andrewlu0 4mo agoi felt like we couldn't build much on top of react-markdown, which i think is what most people are using
- plastic041 4mo agoLooks clean and works fine, but it needs optimization. Clicking "Type" in the "schema builder" example takes 1~2 seconds to open the popover in the landing page(macbook pro m4). I think its because there are lots of heavy components, but still it's too slow.
- andrewlu0 4mo agoit should be much faster on the individual component's page the root page is a bit slow with all the viewers, in practice you probably wont have that many in your app on one page
- phonon 4mo agoHow does it compare to https://news.ycombinator.com/item?id=48436863 https://news.ycombinator.com/item?id=48436863 ?
- andrewlu0 4mo agoif you mean our docx viewer/editor specifically its hard to say without manually testing the visual fidelity with Word on some complex docx files you are welcome to try it with your own documents and see, but its just one example we wanted to show. for the blocks that use the react-docx library, you can always copy the code and use a different method to render the docx file/thumbnails
- topaitools_xyz 4mo ago[flagged]
- qreoct 4mo agoCool project! I was playing around with the Excel viewer - the docs claim "Search across sheets and cell ranges", but I can't seem to trigger search functionality and the browser search bar can't find contents on cells. Is this a known issue?
- andrewlu0 4mo agojust added an example implementation in the xlsx viewer for search, but the code is yours to modify and customize. react-xlsx should expose the necessary functions to implement a custom search (by workbook/sheet etc...)
- qreoct 4mo agoAppreciate the pointer here, this is what I need! Hope this project keeps growing :)
- bschmidt800 4mo ago[dead]
- pea 4mo agoLooks cool but your home page heavily lags on my mbp m3 pro - you should maybe be lazy loading vs loading all your components upfront
- promiseofbeans 4mo agoHow is your PDF coverage? They are notoriously difficult things to render, with endless edge cases. Mozilla’s PSD.js is the status quo here, so what do you do better than them?
- andrewlu0 4mo agoWe use react-pdf for the viewer which I believe uses pdf JS under the hood We aren’t not trying to reinvent that engine, rather just provide a building block for people to plug in their design system to its controls
- carlosjobim 4mo agoExcellent that you offer Miller columns, one of the best tools for computing and information browsing, and management. The world should run on Miller columns.
- andrewlu0 4mo agoTIL those are called Miller columns !
- carlosjobim 4mo agoIf you're on Windows, you can check out ChromaFiler, which takes Miller columns to the next level: https://chroma.zone/chromafiler/ https://chroma.zone/chromafiler/
- cactusplant7374 4mo agoThis is really interesting. Thanks for creating this.
- daohieu91 4mo ago[dead]
- mklifelife 4mo agoLooks great. I'm curious whether the primary users are AI-native document products or more traditional SaaS applications. The document-app niche feels increasingly important with the rise of AI workflows.
- sails 4mo agoprimary use is Document processing automation, or Intelligent Document Processing (IDP)
- rolls-reus 4mo agoMind sharing a link to the source code? i couldn’t find it on the website.
- andrewlu0 4mo agohttps://github.com/extend-hq/ui https://github.com/extend-hq/ui
- rolls-reus 4mo agothanks
- mkl 4mo agoGithub icon in the header on the right.
- sails 4mo agoExperienced the same nightmare a few times over with citations. React/next is limiting, we have rebuilt this for angular and now redid it again using lit for better compatibility. Our old one is very similar to this. Loading citations for each field across 1000s of pages, colliding citations for all the messy formats, zoom, rotate etc. what a mess! Great that you took the time to MIT this as it would have saved us many hours, though I think today Fable + Codex makes it pretty quick I could recreate these in lit as a fork, would be very useful to have the full set
- andrewlu0 4mo agoSomeone requested web components earlier so let me know if you make that happen!
- iamsaitam 4mo agoThe performance on the site is truly terrible, the top animation was probably going at 5fps when scrolling.
- andrewlu0 4mo agoHeard the performance feedback will work on it today!
- wu1064442747 4mo agogood
- lionkor 4mo agoThe performance is quite bad. There are some basics missing or broken. - no caching for file previews - no sorting by date in the file picker - no sorting by size in the file picker - no sorting by file type in the file picker - no search in the file picker - cant enter a folder in the detail view (only expand) in the file picker - cant go to page (by page number) in the document viewer - after clicking a button in the document viewer, focus is lost on the document and arrow keys, space, pgup/pgdown dont work until the document is clicked again - cant select text in the document viewer, unless I search first, in which case it then works This is after looking at the file picker and document viewer less than 3 minutes(!!!). I gave up after that. Getting 80% of a file picker is easy, getting the last 20% done, so that it's on par with existing software, is not. Very very odd to have things look this polished, yet be this terrible functionality- and performance-wise. These are not random quirky new ideas I'm having, these have been basics that work in every single file picker and document viewer since the early days of UI, before the web.
- e12e 4mo agoSince there was a recent thread on react compiler[r] - I wonder if adding/pushing the code through react compiler would help? (Assuming it's not already being used) [r] Thread was about rewrite in rust, but it made me have a look at the purpose/claims made by the project - and fine-grained, automated memoization for speed seems central.
- gobdovan 4mo agoYeah, it also seems it's made in React & Next. From experience, you'll have a hard time choosing a worse technology for low-level, interaction-heavy UI. You need direct control over focus, keyboard handling, scrolling and so on. You also need to leverage hardware accelerated rendering too, which is clunky with 3rd party React libraries. What's more, even if state management should technically be easier with the amount of state libraries, you'll realise sooner or later that the established ones are cleverly immutable where you really just want them to be performant. I am not saying that it's React at fault for the symptoms you see here, but I would expect any such library made in it to hit exactly these kind of edge cases.
- whitephoenix 4mo agoIt looks really great! But, from what I can see, it’ll need some work on optimisation. Good luck with this project, guys!
- andrewlu0 4mo agoThank you! Working on optimizing
- deafpolygon 4mo ago“React components”.. I stopped there.
- peteforde 4mo agoI was excited by the headline but then when I got to the page 1. I saw it was React 2. Nothing loading, just a page full of spinners I truly wish React could be launched into the sun.
- dzonga 4mo agoso slow like molasses
- codingconstable 4mo agoits nice, people are harsh, you did something useful, thank you.
- greenleafone7 4mo agoAnother AI built project. Which OK, but then at least have a look at it to fix/optimize things.
- Lord_Zero 4mo agoDocument Splits drag and drop looks weird, like it doesn't drag from where I clicked.
- kalms 4mo agoSeeing a lot of criticism in here, some valid, some not. Just wanted to say that, to me, this is really well put together - and seems like a lot of thought went into this. Appreciate you releasing this publicly!
- xducn1 4mo ago[flagged]
- grahamstanes17 4mo agoNice