Hi, I'm the creator of Bento. Just wanted to share a bit more about how I created it beyond what's in Github.
The file contains more or less two sections. There is a plain block of JSON near the top of the file which is the slide data. You can read, grep, or point a harness at it. The app itself is in a base64 blob that loads through a small shim which deflates in the browser with DecompressionStream, which keeps the package small and so that we don't need to fetch any external files at runtime. File System Access API is used for JSON writeback into the same file, which falls back to a plian download and all updates are ECDSA signed.
I started with reveal.js which served as a base, and incorporated GSAP/Flip to handle the animation. Then I added charting with echarts, but due to a number of issues with size and how the worked, I ended up re-implementing both.
What I'm most pleased about is how seamless the CRDT works. The blind relay is a small file that runs on Cloudflare Durable Objects, and all it sees are the encrypted data from the clients. Collab is off until we turn it on in the app (by starting a session by sharing by invite file), and then some sets of keys are generated. Access is handled by user key, and you can have read-only users, and also revoke live collab access by user as well.
The project looks very interesting, thanks for sharing!
You seem to have created a new GitHub account just for this project a week ago. Do you have any other GitHub accounts that enable us to see a track record of your work (maintenance, security)?
This was my biggest question. Thanks for preemptively answering (and being proud!).
When I was playing with this, I immediately thought of TiddlyWikis, which I've always been fond of, but they never took for me. However, an easily editable presentation -- that's a use case I can understand.
I couldn't see how there was a CDRT when I'm just working with a single file. I was trying to figure out where the server was. So -- this is just on for everyone? Are you concerned that your Cloudflare account will be hammered with this?
My project for the past few years is called AppDeck, collection of self-contained HTML files that know how to save themselves back to the AppDeck server, which is just WebDAV. AI has been enormously helpful in building out a suite of apps that can do this. So far I have a diagram editor that can produce SVGs, a multi-document editor that backs everything with markdown, but supports Kandan boards, documents, logs, and calendars. I also have a work flowy clone that I've really been enjoying organizing ideas with at work. There's a gallery app that inlines all of the images and can display them full screen in a light box and with a timed slideshow that also supports captions and encryption.
All of it just runs out of a folder on disk and can either be deployed locally or on a server behind a login. I intend to open source it, but I'm not quite proud enough yet of some of the implementation aspects to do so. Hope to do it this summer though!
You can play around in the guestbook. I'm in it right now and you can see me editing things.
Cloudflare Durable Objects are pretty cheap and I'm using it like a very basic pub/sub with each deck having it's own DO. I did some calculations and it should be well within my spend limits.
Something super small that I've noticed in the guestbook: since there're a lot of people connected, I noticed that every time I received an update, I lost the focus of my text element, so it was a little bit difficult to write something.
It may be annoying if two users are working at the same time in the same project.
The concept that's MAGICAL in Reveal.js is vertical slides.
e.g. https://revealjs.com/#/2/1 <-- from here you can go up or down, then go right to continue the presentation.
You just make one slide deck with lightweight high-abstraction slides and depending on the audience you just... hit the down arrow. bam. now you're inside the tech slides. no nerdy tech guys? sweet, don't hit down on slide 3. Instead you're with the marketing guys, so hit down on slide 5.
Anyway - looks like you got rid of that in order to mimic Powerpoint, but... don't forget it's there. it's my favorite part of using Reveal.js!
That's a great point. I went down the state slide route in order to handle a similar type of use-case, but I'll look into this and see if we can incorporate that somehow. It seems like a really elegant way to implement some state slide use cases. And thanks for the heads-up on this!
Yeah, upgrades are pretty seamless so far as the JSON format for the slide data is pretty forgiving. You can also export and reimport the data. It's in the split pill next to Save.
The term "powerpoint" has been genericized in the common vernacular to mean any electronic slide show, like kleenex for tissues and sellotape/scotch tape for transparent adhesive tape.
It might not have reached legal generic status but just about any working professional will understand what you mean if you refer to "making a powerpoint deck" even if you don't use the actual Microslop product.
The docs aren't very polished yet but it's quite usable!
It bundles a JSX transpiler, a code editor, and supports saving to a file or localstorage. It supports "ejecting" to separate the shell (handling saving files, transpiling, editing, etc) from the JSX and the JSON data.
I also threw together an iOS app in which you can save these mini apps, allowing for longer term saving of data and code edits without relying on localstorage alone, making the save/refresh loop seamless. It includes a sandbox, preventing any saved mini apps from making network calls, but allows the user to enable network usage on a per-app basis. I'd like to include more QoL features like a native editor, but haven't prioritized that yet.
This is amazing. I also think this will become more common. I feel there is a lot of software that can just be served locally via html/typescript/react etc and even have local state. There's just not been an economic incentive till now.
I am personally using kimi k3 to create a mobile friendly set of games, starting from math like linear algebra to quantum physics - neurodivergent friendly, completely local state, served from github pages - to get someone interested in the field. This needs an economic incentive to exist without LLMs, because of so much different expertise needed, and time.
if anyone's interested in the games let me know - i plan to play it myself, improve it, remove bugs etc before publishing on HN.
Yeah, I was just discussing with a co-worker the concept of a hybrid document where editing controls and the content all exist in a single HTML file (prior implementations include various wikis such as: https://feather.wiki/ ) --- makes one wonder what an SVG or spreadsheet implementation might look like.
My M1 Mac froze in the end (had to hard-reboot), but that was so much fun! I guess there’s a reason Figma uses WASM and a custom renderer, though I guess your implementation should work fine for most cases (i.e. not when all of HN are trying to edit everything simultaneously :^)
Two notes:
1. It would be nice if another person changing something unrelated to what I’m doing didn’t reset the focus for me.
2. WAY too llm-y copy both on the landing page and the example deck. Your HN submission text is way easier and more pleasant to read.
Thanks! I had to reset the guestbook because it's being spammed. It's on epoch 4 now, hopefully people will be better behaved moving forward!
1. Yes, that's a good point that somebody else raised also. It went pass testing as I was only testing with 1 or 2 other people at once. Will fix this tonight.
2. Yeah, agreed and fair point. But I don't write well and I don't have time between day job and being a dad. Will try to fix this gradually.
1. I’ve added the ⌘V remark on the first slide (it was the only way I could add anything in the previous epoch at all!). Hope it helps others have fun in the meanwhile.
2. Absolutely fair point, and it’s okay – the demo speaks for itself :-) Although if you wrote that submission text yourself, you do write pretty well! But obviously no pressure here.
mdwiki [0] would probably qualify. Disclaimer, I created+released it in 2013. I always jokingly called it the first true single-page application - as it was a single, offline-capable .html file with all images, icons, styles etc. inlined in the same .html file.
Ilograph diagrams can be exported to standalone HTML files (like this example: [0]). Coincidentally, they also have slides (kind of) and clock in at around 560KB.
I love it! I will absolutely be trying this out and following along.
For a long time I've used draw.io for making diagrams, and found it clever that you can effectively save your document as an iframe blob of editor + file (though in their case, the editor is not stored in the file, a web connection is required to load the editor codebase. I've wished that could be the primary use case and this is basically what I'd imagined!
Thanks! As a avid user of draw.io, I consider this model, but ultimately I thought that it's best to start with a single local file. Maybe later when people ask for enterprise-type features it'd make sense to host it. It's definitely needed to do stuff like SSO.
Hey just wanted to say I think this fills an extremely common niche in the corporate world. There are a couple of teams at my company who switched to some variant of fancy html/javascript and away from either cloud or desktop copies of off-the-shelf presentation or visualization software because they were tired of bugs not being fixed or custom features not getting added
Internal IT fiefdoms everywhere should be very afraid
Exactly what we've seen in our company. A lot of techies create these awesome web-app presentations which look awesome and wows everybody, but then some poor person that has Claude but not Claude Code (we somehow decided it was only for techies/SWEs) would then be scratching their heads on what to do because some figures are wrong and they need to update it before the very-important-steerco in the afternoon.
I'm thinking of installing a blank bento for users as a pwa (using browser install site as app), script the author name etc and then make the file read only so they are forced to save as, for users to use as a standalone powerpoint tool.
Maybe you can implement this into the project, a blank default read only (except author details) that installs as a pwa.
I thought about make it a PWA, but I'm still on the fence about hosting in general. Will probably have to host in order to deal with enterprise use-cases, but I just want to make something simple and cool for now. Thanks for the feedback, will explore a bit about what people will want in a hosted solution and how it can keep these principles I think makes it special.
Love it. Like some others here, I've been making html presentations with code-agents and they come out really nice. Other alternatives for that suit different purposes are these:
- typst slides are great looking too, especially with math etc. Again easy for agents to do
One minor nit: Based on the title, I thought this was literally a tool that had something to do with PowerPoint, but "PowerPoint" is used here as a synonym for "Presentation", which is ironic/unfortunate given how many dislike PowerPoint.
Looks very good and I'm excited to try it out properly. It's a shame about the name considering a lot of self-hosters will be using BentoPDF. But thats one of two hard things in Computer Science.
Agreed that the homepage should not indicate otherwise, but on the plus side with a tool like Bento you can edit the HTML file locally, remove the script tag at the bottom that does that, and never worry about that tracking again!
Thanks for raising that. It might be in the standard cloudflare/actors SDK I used for Cloudflare Durable Objects. I'll try to disable this behavour and if we couldn't, we'll rip out DO and replace it with something that doesn't phone home. Apologies I wasn't thorough enough here.
Just an update to this phone home issue. I haven't found anything showing that this should be normal behaviour. I'm thinking this may be due to cloudflare challenges due to the traffic spike. In addition to the DO, the whole website sits behind a Cloudflare proxy.
Will keep chipping away at this and update as I learn more.
Because they didn't write all the code by hand? Seems like an odd measurement for determining if a project is ambitious or impressive. Clearly this one is based on the replies here.
As someone who makes a living in PowerPoint but loves tech and FOSS, congrats. I'm not sure I fully follow how collaborating works, you may want to write an explainer that assumes nearly zero engineering knowledge. Looking forward to the docx and xlsx version, I'll follow on gh to stay up to date
I've been reading HN much longer than I've had an account, and I have never once left a comment or interacted with any post. Had to break the seal to say great job with this. Really fantastic out of the box, and timely thinking. I'll be using this for sure.
I like it. I used Claude and Qwen to build single file HTML decks in the last few months. The nicest thing with HTML decks is that you can not only ship the decks but integrate your prototype/demos in the same file integrated into the flow of your deck. Would love to see a feature like that.
Thanks. That would be a cool feature, and definitely possible. Currently it's already got a feature where you can export and import it's data JSON. We just need to find a way to squeeze a whole frontend in.
I recently did something similar with just asking claude to create me a presentation with GSAP animations. With a some nice features to embed apps, switch the language while presenting, etc. - it works like a charm: https://eos-lci.gitlab.io/eos-lci-presentations/klimabuendni... (all open source)
Was using Reveal.js which worked well because it can use any HTML or any plugin.
Bento works with a predefined schema, so you cant use any HTML library (Such as Mermaid.js) if you need it in your presentation.
But then again, often you dont need it.
Just created a presentation with Bento... I do think Reveal.js gives you more raw power. But I like bentos single html page design, and you can easily edit it manually. You cant do that with Reveal.js
Yup, I'm trying to see if we can add arbitrary JS. I think it may be possible, but would take a bit longer to test out different approaches. However I guess the main target audience for this is coders that interact with non-coders when doing presentations, and I think currently this approach is sufficient.
This blew my socks off. Theres something so satisfying about knowing everything I need is in a single file. I know the caveat is *1. Have a modern browser*, but this is my go to format when trying out random ideas. I even have a macro called `try` that sends me directly to a new folder called `scratch/YYYYMMDD_<try_bento>`.
Great work! I hope to see more and more apps like this in the spirit of "Toss it all into context"
Yeah, unless you were using the guestbook which was being hammered, I'm afraid you are right. I use Firefox, but it's not my main browser and I must confess I didn't do much testing on it. I'll have to look to see how we can improve performance on FF.
This is so cool! When I initially saw the title I was wondering how this is different from SlideJS or similar, but this is really cool and now I'm wondering if this could (at least in theory) be integrated into something like Pandoc as an output option?
Thanks! I'm not familiar with pandoc but I think you can get some data out of the Bento JSON but is not going to be very rich. May be easier to render it to PDF (which works well in Chrome) first.
Maybe? I'm not too familiar with Pandoc's internals so I couldn't say. (I do know it supports templates so maybe you could pull it off like that?) Although I'm wondering if you could just have the JSON as input and then you use pandoc as the transformer and it generates the full HTML file? An interesting idea for sure.
Very cool project! It looks nice and the technical aspect of how sharing/CRDT is implemented is a really great idea! I would definitely be interested in the ability to change the relay; ideally to something self-hosted.
Thanks! That's a really good point. I used Cloudflare DO as it was elegant and convenient, but no reason why we can't run a small daemon to handle the same. I'll work on this later in the week.
Thanks! I guess there are some drawback to this approach, large companies especially would be completely adverse to it. But it's cool and I'm hoping people would find it useful!
For people clicking on a link to some slides that someone shared, it seems like starting out in viewing mode with a prominent edit button might be better than starting out in edit mode?
Some unexpected behavior: I reloaded the page, double-tapped on the first slide to go back to it, then hit slideshow. Instead of starting out on the slide like I chose, it went to a slide further in othe presentation. I think it’s a bit too persistent about resuming where you left off?
Also, swiping left to get back to the first slide puts me back in the editor (I went too far), and then hitting slideshow puts me back where I started so I have to swipe left again.
Also, viewing slides on a tablet, I don’t see a way to open speaker notes since I can’t “press the S key.” These instructions should probably be different if you’re not on desktop.
Maybe display speaker notes by default if the screen is in portrait mode?
The slideshow button is a split pill, you can open it there where there is this tiny up arrow that opens up a drop down menu. But on tablet it probably doesn't do what you want it to as it was built for multi-screen use on the desktop.
I'll have a think on this tonight and I'm sure we can do a tablet speaker notes mode.
I'm a bit worried on the UX on mobile, so I did some testing to get at least the basic working! Video also worked better than expected, I love how the video background in the Orbital deck turned out! Thanks for the feedback!
I’ve honestly been kind of surprised that large companies software hasn’t been recreated for free en masse from the use of AI in a weekend. I’ve definitely seen some cases but it’s not as common as I had personally expected.
Thanks! I started on this last week in my spare time and I used Claude, all my commit history is on Github. I did most of the coding via Claude Code, no fancy system or exotic harness.
I would love to do more by hand, but I look after a tech team inside a renewables firm, so I don't have much time between job and my preschooler.
this project is a monument to the HUGE failure of the Workspace team at Google to enable agent editing in a way that makes sense.
Google is really shitting the bed in all the way that matters on GenAI and being an ex employee of Cloud I am not in the least surprised about it, just really sad.
Why does the homepage mention AI over 20 times? Why does it mention AI at all? Why is most of it absurdly long and obfuscated base 64, which looks be binary data?
It's really to solve a use case where there are a lot of these cool web-based presentations being created by AI, but they are all disposable things that non-technies can't work with easily.
Base64 is paired with compression to keep the size small so you can share it easily. The original version was around 1.3MB and maybe we can have a switch to output without compression. The source that generates it is all in Github.
Because whatever you like or not, AI support these days is a must. Nobody who makes PPT does everything by hand nowadays. And the project is on GitHub, you can get the full code there if you must...
Thanks! It's a project I did in my spare time and it's made with a lot of MIT licensed JS libraries, so it's natural to make this MIT licensed as well. I don't know even know how anybody would start to monetise something local-first like this in this day and age.
Did you chew on monetization at all? I'm building something similar but for bio-imaging scientists, where I've packed everything I can into a single HTML (and even some modern segmentation models like Cellpose3 and StarDist that fit under Cloudflare's 25MB free tier limit haha.
Maybe I'm thinking too far ahead but I'm hoping maybe I can cover the (future?) compute costs by charging for the heavy duty ML that would have to be run non-locally but IDK. This isn't critical yet but would love to hear your musings.
If you have a backend that does processing, I'm sure you can monetise it. But for Bento, the whole idea is to forgo the backend, so I didn't really think about it that much. If an enterprise version comes, I'm sure there is a way to integrate stuff like SSO that you can charge for.
Hi, I'm the creator of Bento. Just wanted to share a bit more about how I created it beyond what's in Github.
The file contains more or less two sections. There is a plain block of JSON near the top of the file which is the slide data. You can read, grep, or point a harness at it. The app itself is in a base64 blob that loads through a small shim which deflates in the browser with DecompressionStream, which keeps the package small and so that we don't need to fetch any external files at runtime. File System Access API is used for JSON writeback into the same file, which falls back to a plian download and all updates are ECDSA signed.
I started with reveal.js which served as a base, and incorporated GSAP/Flip to handle the animation. Then I added charting with echarts, but due to a number of issues with size and how the worked, I ended up re-implementing both.
What I'm most pleased about is how seamless the CRDT works. The blind relay is a small file that runs on Cloudflare Durable Objects, and all it sees are the encrypted data from the clients. Collab is off until we turn it on in the app (by starting a session by sharing by invite file), and then some sets of keys are generated. Access is handled by user key, and you can have read-only users, and also revoke live collab access by user as well.
The project looks very interesting, thanks for sharing!
You seem to have created a new GitHub account just for this project a week ago. Do you have any other GitHub accounts that enable us to see a track record of your work (maintenance, security)?
This was my biggest question. Thanks for preemptively answering (and being proud!).
When I was playing with this, I immediately thought of TiddlyWikis, which I've always been fond of, but they never took for me. However, an easily editable presentation -- that's a use case I can understand.
I couldn't see how there was a CDRT when I'm just working with a single file. I was trying to figure out where the server was. So -- this is just on for everyone? Are you concerned that your Cloudflare account will be hammered with this?
My project for the past few years is called AppDeck, collection of self-contained HTML files that know how to save themselves back to the AppDeck server, which is just WebDAV. AI has been enormously helpful in building out a suite of apps that can do this. So far I have a diagram editor that can produce SVGs, a multi-document editor that backs everything with markdown, but supports Kandan boards, documents, logs, and calendars. I also have a work flowy clone that I've really been enjoying organizing ideas with at work. There's a gallery app that inlines all of the images and can display them full screen in a light box and with a timed slideshow that also supports captions and encryption.
All of it just runs out of a folder on disk and can either be deployed locally or on a server behind a login. I intend to open source it, but I'm not quite proud enough yet of some of the implementation aspects to do so. Hope to do it this summer though!
You can play around in the guestbook. I'm in it right now and you can see me editing things.
Cloudflare Durable Objects are pretty cheap and I'm using it like a very basic pub/sub with each deck having it's own DO. I did some calculations and it should be well within my spend limits.
Something super small that I've noticed in the guestbook: since there're a lot of people connected, I noticed that every time I received an update, I lost the focus of my text element, so it was a little bit difficult to write something.
It may be annoying if two users are working at the same time in the same project.
Again, very cool project! :)
The concept that's MAGICAL in Reveal.js is vertical slides.
e.g. https://revealjs.com/#/2/1 <-- from here you can go up or down, then go right to continue the presentation.
You just make one slide deck with lightweight high-abstraction slides and depending on the audience you just... hit the down arrow. bam. now you're inside the tech slides. no nerdy tech guys? sweet, don't hit down on slide 3. Instead you're with the marketing guys, so hit down on slide 5.
Anyway - looks like you got rid of that in order to mimic Powerpoint, but... don't forget it's there. it's my favorite part of using Reveal.js!
That's a great point. I went down the state slide route in order to handle a similar type of use-case, but I'll look into this and see if we can incorporate that somehow. It seems like a really elegant way to implement some state slide use cases. And thanks for the heads-up on this!
Nice idea. What happens if you upgrade to v2 and my slide decks are on v1?
Can I click upgrade and get the JSON slide deck data exported into a v2 shell?
Yeah, upgrades are pretty seamless so far as the JSON format for the slide data is pretty forgiving. You can also export and reimport the data. It's in the split pill next to Save.
I would call this a slide show not powerpoint mostly because making it work with the satanic office formats is a path to hell.
Hopefully simpler formats like this will become the norm and the old ones can die.
You are right, but I guess a lot of people recognise PowerPoint as a brand. Maybe I can bill this as better-than-powerpoint!
FactorialPoint, your slideshows improve even faster than an exponential!
Hehe, if we go in the other direction we can call it basepoint.
The term "powerpoint" has been genericized in the common vernacular to mean any electronic slide show, like kleenex for tissues and sellotape/scotch tape for transparent adhesive tape.
It might not have reached legal generic status but just about any working professional will understand what you mean if you refer to "making a powerpoint deck" even if you don't use the actual Microslop product.
I recently made a very similar tool but focused on making small React apps instead of presentations.
A basic starter html file with an example app: https://glider-app.netlify.app/glider.html
Docs: https://glider-app.netlify.app/docs.html
The docs aren't very polished yet but it's quite usable!
It bundles a JSX transpiler, a code editor, and supports saving to a file or localstorage. It supports "ejecting" to separate the shell (handling saving files, transpiling, editing, etc) from the JSX and the JSON data.
I also threw together an iOS app in which you can save these mini apps, allowing for longer term saving of data and code edits without relying on localstorage alone, making the save/refresh loop seamless. It includes a sandbox, preventing any saved mini apps from making network calls, but allows the user to enable network usage on a per-app basis. I'd like to include more QoL features like a native editor, but haven't prioritized that yet.
https://apps.apple.com/app/id6790498430
This is amazing. I also think this will become more common. I feel there is a lot of software that can just be served locally via html/typescript/react etc and even have local state. There's just not been an economic incentive till now.
I am personally using kimi k3 to create a mobile friendly set of games, starting from math like linear algebra to quantum physics - neurodivergent friendly, completely local state, served from github pages - to get someone interested in the field. This needs an economic incentive to exist without LLMs, because of so much different expertise needed, and time.
if anyone's interested in the games let me know - i plan to play it myself, improve it, remove bugs etc before publishing on HN.
Yeah, I was just discussing with a co-worker the concept of a hybrid document where editing controls and the content all exist in a single HTML file (prior implementations include various wikis such as: https://feather.wiki/ ) --- makes one wonder what an SVG or spreadsheet implementation might look like.
Thanks! If you need anybody to test and feedback, I'll give it a go.
https://vecto.play.naigap.com/
https://phaseworld.play.naigap.com/
https://slope-rider.play.naigap.com
Three so far Repos -
https://github.com/praveer13/vecto
https://github.com/praveer13/slope-rider
https://github.com/praveer13/phase-world
This is so cool. And it's as simple as telling Claude about the skill: https://bento.page/
> Go to https://bento.page/guestbook/ to try out the live guestbook to experience share editing / collab.
My M1 Mac froze in the end (had to hard-reboot), but that was so much fun! I guess there’s a reason Figma uses WASM and a custom renderer, though I guess your implementation should work fine for most cases (i.e. not when all of HN are trying to edit everything simultaneously :^)
Two notes:
1. It would be nice if another person changing something unrelated to what I’m doing didn’t reset the focus for me.
2. WAY too llm-y copy both on the landing page and the example deck. Your HN submission text is way easier and more pleasant to read.
And huge kudos for releasing this as FOSS!
Thanks! I had to reset the guestbook because it's being spammed. It's on epoch 4 now, hopefully people will be better behaved moving forward!
1. Yes, that's a good point that somebody else raised also. It went pass testing as I was only testing with 1 or 2 other people at once. Will fix this tonight.
2. Yeah, agreed and fair point. But I don't write well and I don't have time between day job and being a dad. Will try to fix this gradually.
1. I’ve added the ⌘V remark on the first slide (it was the only way I could add anything in the previous epoch at all!). Hope it helps others have fun in the meanwhile.
2. Absolutely fair point, and it’s okay – the demo speaks for itself :-) Although if you wrote that submission text yourself, you do write pretty well! But obviously no pressure here.
Awesome. I've been trying to promote this kind of Single-File Web Apps as a concept - feel free to add this to the proposed Wikipedia page: https://en.wikipedia.org/wiki/Draft:Single_File_Web_Apps
mdwiki [0] would probably qualify. Disclaimer, I created+released it in 2013. I always jokingly called it the first true single-page application - as it was a single, offline-capable .html file with all images, icons, styles etc. inlined in the same .html file.
[0]: https://mdwiki.info
The draft doesn't read as a Wikipedia article – e.g. addressing the reader as 'you'.
I don't think WP is the right place for this. It is supposed to be a tertiary source, not a place to promote concepts you want to see established.
Ilograph diagrams can be exported to standalone HTML files (like this example: [0]). Coincidentally, they also have slides (kind of) and clock in at around 560KB.
[0] https://www.ilograph.com/demo/intelligentDocumentProcessing....
https://hyperclay.com/ could be on there I think
I looked at adding hyperclay, but I think it requires server-side code.
Thanks for sharing this! Let me take a look. I was only aware of TiddlyWiki when I first started on Bento.
http://beyondloom.com/decker/
I love it! I will absolutely be trying this out and following along.
For a long time I've used draw.io for making diagrams, and found it clever that you can effectively save your document as an iframe blob of editor + file (though in their case, the editor is not stored in the file, a web connection is required to load the editor codebase. I've wished that could be the primary use case and this is basically what I'd imagined!
Thanks! As a avid user of draw.io, I consider this model, but ultimately I thought that it's best to start with a single local file. Maybe later when people ask for enterprise-type features it'd make sense to host it. It's definitely needed to do stuff like SSO.
Hey just wanted to say I think this fills an extremely common niche in the corporate world. There are a couple of teams at my company who switched to some variant of fancy html/javascript and away from either cloud or desktop copies of off-the-shelf presentation or visualization software because they were tired of bugs not being fixed or custom features not getting added
Internal IT fiefdoms everywhere should be very afraid
Exactly what we've seen in our company. A lot of techies create these awesome web-app presentations which look awesome and wows everybody, but then some poor person that has Claude but not Claude Code (we somehow decided it was only for techies/SWEs) would then be scratching their heads on what to do because some figures are wrong and they need to update it before the very-important-steerco in the afternoon.
I'm thinking of installing a blank bento for users as a pwa (using browser install site as app), script the author name etc and then make the file read only so they are forced to save as, for users to use as a standalone powerpoint tool.
Maybe you can implement this into the project, a blank default read only (except author details) that installs as a pwa.
I thought about make it a PWA, but I'm still on the fence about hosting in general. Will probably have to host in order to deal with enterprise use-cases, but I just want to make something simple and cool for now. Thanks for the feedback, will explore a bit about what people will want in a hosted solution and how it can keep these principles I think makes it special.
Love it. Like some others here, I've been making html presentations with code-agents and they come out really nice. Other alternatives for that suit different purposes are these:
- slidev markdown-based slides, I often have a code-agent make these. https://github.com/slidevjs/slidev
- typst slides are great looking too, especially with math etc. Again easy for agents to do
One minor nit: Based on the title, I thought this was literally a tool that had something to do with PowerPoint, but "PowerPoint" is used here as a synonym for "Presentation", which is ironic/unfortunate given how many dislike PowerPoint.
Looks very good and I'm excited to try it out properly. It's a shame about the name considering a lot of self-hosters will be using BentoPDF. But thats one of two hard things in Computer Science.
Aw man! Well it is very different to what BentoPDF is doing. I'm sure nobody would get confused!
What an ambitious and impressive project! I'm going to try it.
One note: The home page says "Nothing phones home," but the Bento files I've examined include a cloudflareinsights.com beacon.
> include a cloudflareinsights.com beacon.
Agreed that the homepage should not indicate otherwise, but on the plus side with a tool like Bento you can edit the HTML file locally, remove the script tag at the bottom that does that, and never worry about that tracking again!
Thanks for raising that. It might be in the standard cloudflare/actors SDK I used for Cloudflare Durable Objects. I'll try to disable this behavour and if we couldn't, we'll rip out DO and replace it with something that doesn't phone home. Apologies I wasn't thorough enough here.
Just an update to this phone home issue. I haven't found anything showing that this should be normal behaviour. I'm thinking this may be due to cloudflare challenges due to the traffic spike. In addition to the DO, the whole website sits behind a Cloudflare proxy.
Will keep chipping away at this and update as I learn more.
By ambitious and impressive do you mean for Claude?
Because while cool this is clearly heavily vibe coded.
I'm don't care. If it's good, it's good.
Agreed, but the days of software projects being ambitious or impressive are over.
Because they didn't write all the code by hand? Seems like an odd measurement for determining if a project is ambitious or impressive. Clearly this one is based on the replies here.
As someone who makes a living in PowerPoint but loves tech and FOSS, congrats. I'm not sure I fully follow how collaborating works, you may want to write an explainer that assumes nearly zero engineering knowledge. Looking forward to the docx and xlsx version, I'll follow on gh to stay up to date
I love this.
I hope you don't get cease and desisted by MS for mentioning PowerPoint.
I've been reading HN much longer than I've had an account, and I have never once left a comment or interacted with any post. Had to break the seal to say great job with this. Really fantastic out of the box, and timely thinking. I'll be using this for sure.
Thanks! It's also my first submission to HN after reading and commenting on here for the last 7 years!
I like it. I used Claude and Qwen to build single file HTML decks in the last few months. The nicest thing with HTML decks is that you can not only ship the decks but integrate your prototype/demos in the same file integrated into the flow of your deck. Would love to see a feature like that.
Thanks. That would be a cool feature, and definitely possible. Currently it's already got a feature where you can export and import it's data JSON. We just need to find a way to squeeze a whole frontend in.
I really loved when this was a feature of the Opera browser, before they went chromium.
I used Opera for a while, but I didn't recall it doing this. Do you have a link to show what it was able to do?
I recently did something similar with just asking claude to create me a presentation with GSAP animations. With a some nice features to embed apps, switch the language while presenting, etc. - it works like a charm: https://eos-lci.gitlab.io/eos-lci-presentations/klimabuendni... (all open source)
Was using Reveal.js which worked well because it can use any HTML or any plugin.
Bento works with a predefined schema, so you cant use any HTML library (Such as Mermaid.js) if you need it in your presentation.
But then again, often you dont need it.
Just created a presentation with Bento... I do think Reveal.js gives you more raw power. But I like bentos single html page design, and you can easily edit it manually. You cant do that with Reveal.js
Yup, I'm trying to see if we can add arbitrary JS. I think it may be possible, but would take a bit longer to test out different approaches. However I guess the main target audience for this is coders that interact with non-coders when doing presentations, and I think currently this approach is sufficient.
This blew my socks off. Theres something so satisfying about knowing everything I need is in a single file. I know the caveat is *1. Have a modern browser*, but this is my go to format when trying out random ideas. I even have a macro called `try` that sends me directly to a new folder called `scratch/YYYYMMDD_<try_bento>`.
Great work! I hope to see more and more apps like this in the spirit of "Toss it all into context"
Thanks, you're right, that is the achilles heel. Most of the functionality actually is in the browser. We're just running fancy scripting on it.
This might just be a Firefox thing but the animations are really struggling on my system here - very slow and choppy.
Yeah, unless you were using the guestbook which was being hammered, I'm afraid you are right. I use Firefox, but it's not my main browser and I must confess I didn't do much testing on it. I'll have to look to see how we can improve performance on FF.
This looks like a great idea, thanks for sharing it!
This is so cool! When I initially saw the title I was wondering how this is different from SlideJS or similar, but this is really cool and now I'm wondering if this could (at least in theory) be integrated into something like Pandoc as an output option?
Thanks! I'm not familiar with pandoc but I think you can get some data out of the Bento JSON but is not going to be very rich. May be easier to render it to PDF (which works well in Chrome) first.
Maybe? I'm not too familiar with Pandoc's internals so I couldn't say. (I do know it supports templates so maybe you could pull it off like that?) Although I'm wondering if you could just have the JSON as input and then you use pandoc as the transformer and it generates the full HTML file? An interesting idea for sure.
Very cool project! It looks nice and the technical aspect of how sharing/CRDT is implemented is a really great idea! I would definitely be interested in the ability to change the relay; ideally to something self-hosted.
Thanks! That's a really good point. I used Cloudflare DO as it was elegant and convenient, but no reason why we can't run a small daemon to handle the same. I'll work on this later in the week.
This is awesome! I do love this software is one file thing. A breath of fresh air on these you-rent-everything-owns-nothing days
Thanks! I guess there are some drawback to this approach, large companies especially would be completely adverse to it. But it's cool and I'm hoping people would find it useful!
Absolutely love seeing products like this. Starred, saved link, will definitely use soon.
Thanks, people asked about monetization but seriously Github stars is really all it's about.
This is excellent work!
Thanks for sharing and deserves a lot of Github stars!
This is very neat!
For people clicking on a link to some slides that someone shared, it seems like starting out in viewing mode with a prominent edit button might be better than starting out in edit mode?
Thanks for the feedback, that's a really good idea! I'll try to roll it out shortly!
Some unexpected behavior: I reloaded the page, double-tapped on the first slide to go back to it, then hit slideshow. Instead of starting out on the slide like I chose, it went to a slide further in othe presentation. I think it’s a bit too persistent about resuming where you left off?
Also, swiping left to get back to the first slide puts me back in the editor (I went too far), and then hitting slideshow puts me back where I started so I have to swipe left again.
The slide resume behaviour is definitely a bug, I'll take a stab at it shortly.
The swipe left on first slide is a feature though, its to help mobile users get back to the editor easily.
Also, viewing slides on a tablet, I don’t see a way to open speaker notes since I can’t “press the S key.” These instructions should probably be different if you’re not on desktop.
Maybe display speaker notes by default if the screen is in portrait mode?
The slideshow button is a split pill, you can open it there where there is this tiny up arrow that opens up a drop down menu. But on tablet it probably doesn't do what you want it to as it was built for multi-screen use on the desktop.
I'll have a think on this tonight and I'm sure we can do a tablet speaker notes mode.
This is really clever and is taking a direction I hope to see more software taking! Totally self contained is awesome. Well done!
Thanks! I hope it's good and practical enough to be actual useful (and used regularly by pepole).
I really like it, you are a genius
Awesome. Perfect for editing with agents and sharing with coworkers.
- Even works well on mobile.
- Embedding images and videos also works flawlessly.
I'm a bit worried on the UX on mobile, so I did some testing to get at least the basic working! Video also worked better than expected, I love how the video background in the Orbital deck turned out! Thanks for the feedback!
Love that it's just one HTML file, really easy way to share software. Great work!
Great project. But please check the name:
https://en.wikipedia.org/wiki/Bento_(database)
That's a reason for downvoting me?! I made a nice and respectful comment.
> Bento is a discontinued database application for Mac OS X made by the former FileMaker Inc., since renamed to Claris.
So OP needs to rename their slideshow tool to Claris?
Bento is perfect reasonable name for an all in one solution - no?
https://en.wikipedia.org/wiki/Bento
It's also the name of a CMS from PBS that's been used for years:
https://docs.pbs.org/space/B3/4751362/Bento+3.0
OMG coming from bigtime consulting this is...AMAZING. Thank you!
Yeah, if you do a lot of slides, this is for you! The whole point of this is to make doing slides bearable!
if you extract ppt it is a xml file !! fyi !
I’ve honestly been kind of surprised that large companies software hasn’t been recreated for free en masse from the use of AI in a weekend. I’ve definitely seen some cases but it’s not as common as I had personally expected.
>There's no install or cloud login, everything works offline. The default deck is around 560 KB and it doesn't need to fetch anything once you got it.
This is the best feature.
Great job! How long did this project take total? How much percent is AI generated?
Thanks! I started on this last week in my spare time and I used Claude, all my commit history is on Github. I did most of the coding via Claude Code, no fancy system or exotic harness.
I would love to do more by hand, but I look after a tech team inside a renewables firm, so I don't have much time between job and my preschooler.
Are you kidding me? I gave it a spin, and it's solid. That's crazy, I'm impressed!
Looks nice, but I'd love to have a setting where all animations can be switched off.
Good idea! Let me roll that out. I guess you can also print to PDF.
This is awesome!
this project is a monument to the HUGE failure of the Workspace team at Google to enable agent editing in a way that makes sense.
Google is really shitting the bed in all the way that matters on GenAI and being an ex employee of Cloud I am not in the least surprised about it, just really sad.
I like a bit of good gossip. If you're based in London, let's go out for a beer.
impressive, bravo!
Why does the homepage mention AI over 20 times? Why does it mention AI at all? Why is most of it absurdly long and obfuscated base 64, which looks be binary data?
It's really to solve a use case where there are a lot of these cool web-based presentations being created by AI, but they are all disposable things that non-technies can't work with easily.
Base64 is paired with compression to keep the size small so you can share it easily. The original version was around 1.3MB and maybe we can have a switch to output without compression. The source that generates it is all in Github.
Because whatever you like or not, AI support these days is a must. Nobody who makes PPT does everything by hand nowadays. And the project is on GitHub, you can get the full code there if you must...
Um, that's amazing... and it's free?
Thanks! It's a project I did in my spare time and it's made with a lot of MIT licensed JS libraries, so it's natural to make this MIT licensed as well. I don't know even know how anybody would start to monetise something local-first like this in this day and age.
Did you chew on monetization at all? I'm building something similar but for bio-imaging scientists, where I've packed everything I can into a single HTML (and even some modern segmentation models like Cellpose3 and StarDist that fit under Cloudflare's 25MB free tier limit haha.
Maybe I'm thinking too far ahead but I'm hoping maybe I can cover the (future?) compute costs by charging for the heavy duty ML that would have to be run non-locally but IDK. This isn't critical yet but would love to hear your musings.
If you have a backend that does processing, I'm sure you can monetise it. But for Bento, the whole idea is to forgo the backend, so I didn't really think about it that much. If an enterprise version comes, I'm sure there is a way to integrate stuff like SSO that you can charge for.
Also, bento: https://github.com/chef/bento. No relation.