PyScript - Run Python in the Browser! THE END of JavaScript??? 

i cant believe this, neither can i imagine the complexity of the code in the pyscript's CSS and JS files. These guys are real legends!

The fact that its made by the Anaconda team puts me at ease that its here to stay and will only improve with time. Pretty awesome, the future of web dev is changing so fast.

Guys, before talking about how it can replace JS please check PyScript-s performance. Python by itself is kinda slow, and this makes it even slower. For example, it tasks about 1s to print current datetime. Also, why would data scientist need library for web? No, I don't think it will replace JS any time sooner, if ever. Also, I don't want to think about XSS attacks and similar stuff.

WASM has been around for years and there are even Rust, C#, Kotlin etc. front end frameworks... and they did shit to JS. So short answer is no

Developers: we want webassembly and faster page loads to eliminate the need of desktop development Also developers: lets add even a slower scripting language in another py2js interpretion layer and also don't allow the code to be minified for production since python relies on indentation. Also developers: we hate javascript but it pays the bills Personally: typescript, sass, nextjs and mongodb atlas or cockroachdb cloud for the win

Not the end of JavaScript for sure, but a cool project nonetheless.

Incredible. It's one of the best news I have had in these last two months. And it's also backed by a big and professional team, like Anaconda's one! Hope this video is watched by more ;)

That's really great. Anaconda team keeps innovating!

Very cool, thanks for bringing this to my attention.. Digging in. Ty

This is just javascript which converts Python to js...

wow! What's next? Quantum computing in the browser... I see it in the future. this is very nice

Now all we need is Golang to develop web site capabilities as well. Sorry recently tried out GO and I kind of like the language. Only thing is, is Golang ever going to become popular, I hope so.... But Golang is so new. I know this isn't about Golang but Python, but Golang is similar to Python from the little experience I had with it, and it is also a very powerful language to learn, it is a low lever language and simple to write with.

wouaouw !! what crazy stuff is going to append within 2 years with this new tool ? python in the browser is a milestone for web developpers. It's a bit like if a second javascript was born but with an insanely large community already in place

This looks incredible!

I'm interested in your demonstration codes. But I don't know how to get the exact code you typed in the video clip here. Please let me know if you have extra moments. I like your works.

wait ... what ? how freaking cool is this. So lets build something. just yesterday I get made because I want to make a dashboard in Excel. this is now the better solution :).

I use wordpress custom html block to add calculator any other thing that I built using html, css and js code. Now can we use pyton code also in wordpress?

Excellent video. I have a question, how will new packages be installed in pyscrit with pip?

Great video. Pleas consider making a follow-up with forms.

A word on your clickbait title. If writing a script in something other than pure JavaScript that first gets compiled into pre ES6 JS anyway means "the death of JavaScript" then JS died way back in the jQuery days in 2010s. There is no doubt that this framework is really great and the anaconda team deserve an applause, but I really can't help but feel disgusted by clickbaits like this

I have a question dear friends! Is there a way to create a downloadable file with pyscript? I would like to be able to do this because it would simplify what I am doing. Thanks!

I don't know much about this stuff. Does this mean I can manipulate the DOM with python?

Wow Sir, you made it simple for me, Thanks, thanks, thanks 🙏. This is super 😎.

Does it uses Client-side or Server side CPU power? Is it possible to save server computation resource with this ?

I have a multi files script to run and I need to import pygame. Can I do it with this method ? In fact, I'm trying to make a chess game on my wordpress website, and I don't want to pay €40/month to use their python plugins

The CDN pyscript javascript files is 1.2MB. A pity browser can't just bundle in python support in addition to javascript, e.g.

Can someone help me with this? Um... when I use pyscript with html and then run the program, it doesn't show the output, It just shows the python code. Like it will just display print ("hello world") instead of "hello world". If someone can help me fix this that would be great. I'm on windows.

Nothing can replace core javascript

Holy crap!!! Amazing!!!!

Great ! Thank you !!!

Long live JavaScript!!! No one can beat JavaScript. Everyone is jealous of JavaScript because it's the only language used in frontend. Whatever you do whatever language you use at the end it needs to be transpiled to JavaScript JavaScript you are the king. Whatever comes will need to kneel in front of you.

Death of Javascript? Not if pyscript runs so slow. But then, this is just the beginning. For Javascript to be replaced by anything sane would make me happy! I'll be watching this project.

Why wouldn’t I just write my code in Python and then compile to WASM if I wanted this? Isn’t there going to be a significant difference in performance if it’s just straight Python?

Didn't work for me. Can you help me?

I dont think js is ever going away. There is just too much dependency on it. But the fact that this is even possible is very exciting. It will be interesting to see how this evolves. I see full stack Python webapps in the future.

instead of they should have ideally used but i do see how that was not possible assuming that the py-script tag is probably a web component

"The end of javascript" Is always coming according to everyone... but It's not going away anytime soon

They should invest more time in improving wasm so you can use wherever kind of language you're confortable with. Imagine if you could easily manipulate the DOM through wasm, this will really change web development!

Wish we could have a dedicated Python Frontend Framework..... Can't wait to experience that.

This is a really cool project, but honestly the only reason I can see for using it is bringing awesome python libs like matplotlib, pandas, sympy etc. to the browser. For the rest I see no reason or need to use it, the javascript ecosystem is huge and powerful. Why would any frontend developer switch to the python apis if he or she is comfortable in the js apis? Only thing is that this makes the web more accessible for python developers and lowers the threshold to get started with frontend development for them. That's a good thing for sure, but it won't change the industry imo.

"It will take a few moments" ... I see we get the full python experience in the browser 😅

Congratulations, now I can execute my DOM code more slowly🙂

So basically you write python, that's translated into javascript. Sure thing, that this is future, because js is already so fast to easily compile code and we need one extra step.

I mean... I get it, for use cases where you really need specific Python packages... But not without some SERIOUS performance issues. This comes from just the Hello World Example 1. 290 kb of CSS and 300 kb of JS dependencies 2. 7 *MB* for the Python interpreter 3. 1.2 *MB* for dependencies Just for a Hello World example. Unless this gets built into browsers natively, you're absolutely gonna KILL your site's performance. Almost 9MB you can't get rid of is an INSANE amount of data, and on top you're running a Python interpreter in webassembly. Use sparingly when you have no alternatives left.

I guess I'd like to see more focus on just making python compile to webassembly really well.

end of javascript? of course not ahah

Interesting find but the clickbait title is leading to a lot of dumb comments about Python replacing JS -it’s clear that this is a Python to JS compiler so JS will always be used as the end result. Just importing a bunch of Python files in the index.html file will get really hard to maintain and code-split which led to JS web frameworks and libraries being adopted and now widely used. So definitively JS is not being replaced by PScript and JS web development positions will not magically be replaced with Python. I know you understand it, it’s just for the annoying people always thinking there is some war of dominance for which language to rule them all. Best thing as usual to learn both JS and Python, and decide which one is best suited for your case. PScript will be super useful for Python data scientists wanting to create a website that is not just a hosted Jupiter notebook, and lots of other applications that will be exciting to see!

"The end of Javascript". For educational purposes, if you remove the V8 runtime from your browser your script will no longer work. The video is intuitive despite the title, don't do this. It has already been demonstrated many times by many contributors of Python, Chromium and Mozilla that Python is not suitable for the Web. Anyway, people are used to using JS which is undoubtedly the language of the Web and will never be replaced simply because it would break more than 3/4 of the current Web. Also, the V8 JIT compiler performs better than the Python one, I base this on my own tests as a JIT compiler developer. And it is optimized for the web to reduce the memory footprint, unlike Python which was not designed with this in mind. If you want to use Python on the Web only because you miss Tensorflow and Keras, either follow the documentation and install them locally, or wait a few months until the GPU Web API and other machine learning APIs are available on Chrome. This will be much more efficient than using a port of the Python runtime in WebAssembly. At least 10 times more.

It is a nice idea and might be awesome for the hard core python fans. But my concern is that this sacrifices the user experience in exchange for dev experience, which is certainly the wrong way around. After all, each user has to download the python interpreter, and the code will run a lot slower than javascript, since python is not optimized by the browser. Additionally a lot of pythons performance comes from super fast packages like numpy that are written in C, however these are slowed down significantly through webassembly. Because under the hood webassembly uses the same VM code as javascript, so WebAssembly performance == JavaScript performance.

Created using javascript and still talking about killing javascript! Get out! People spent their most life learning javascript and related frameworks and just starting their career and then guys like you come and say kill javascript and learn python! That means I have more burden to lift when applying for a job!

When I think about python front end, components as objects comes to mind. PyScript reminds me Kivy in some ways, a great project that is always "experimental"

The fact that we can run in the browser python through WASM is cool for trivial stuff but I don't know... There are already so many issues and concerns about bundle sizes and performance in all JavaScript frameworks that I can't imagine how messy it can get with PyScript if people will start to use it for general-purpose Web Development.

Wow, very excited on what this becomes in a few years. Lot's of potential for big data visualizations.

I took a look at it, its super interesting. However, right now it seems to much of a mixture of things, I still was using JS when I tried integrating a simple target practice game. I can see useful reasons to have Python integrated into HTML. However, I don't see this doing better then JavaScript.

As someone who works with both JavaScript and Python, I can assure you that even though this is a nice proof of concept, no front-end developer in their right mind would ever touch something like this. The JavaScript ecosystem is just so much more mature than Python's that it's basically impossible to catch up at this point. Think about the different between NPM and PIP. One is a proper packages manager, the other doesn't even handle requirement files decently. Other example would be, say, the import systems in both languages; JavaScript's is concise, efficient and easy to understand, meanwhile, Python's is a mess. I understand that a lot of people will always try to use anything for the web but JavaScript in the same way that americans will measure with anything but the metric system, but at some point they will have to understand that it is, and will continue to be for the foreseeable future, the best language to build interfaces. Period. It's the language's purpose, and it's why people will use it everywhere. Web? JavaScript. Mobile? JavaScript with React Native or Cordova or Ionic. Desktop? JavaScript with Electron or Tauri or (who remembers?) NW.JS. I mean, if we're really being honest, the reason augmented reality is not mainstream os probably because there's no JavaScript frameworks for it. Don't get me wrong, I love Python, and as of now, it's my main source of income, but it's simply not meant to compete with JavaScript in the the things JavaScript is good at. TLDR; if I ever see a job offer from a company that has this in it's stack, I'll know to stay away from it, for they're clearly out of their minds.

I think most of the people aren't understanding the true impact something like this would make possible: "In other words, PyScript allows you to use Python, with or without JavaScript, to build interactive websites that don’t necessarily have to communicate with a server. " In other words, you could have a photo sharing website, with nothing on the web server. Which means you don't need to login to flickr or instagram to do photo sharing, because there is no backend and the sharing could be done peer to peer (like torrents). Which also means you just need a directory on a server that just serves files, without any further intelligence. This has been an idea for a long time now.

This is very exciting, Thank you for informing us about it, now as pythonistas we must contribute and build a community about pyscript :D

Python interpreted with js .. I can imagine the execution time !!

Great, because Skulpt was so successful. Its a JS script hence 'interoperability with JS.' Python to Emscripten compiler. It needs JS, how would it replace it? Go home python, youre drunk.

Firstly, Python sucks without curly braces. Secondly, I didn't see any major advantages for Python to work in browser than JavaScript.

python will never replace javascript.

Next thing in life, (future) you will see people working in it and getting unbelievable good. Thus, it will become a meta (just predictions).

My guy no one users javascript these days all you see is react react . 90% of the front end developers are scared of javascript I don't know why very hard to find a full stack development tutorial using pure javascript

This is a really interesting project

A language you can't even write in Notepad where a wrong space can wreak havoc on your code, and for someone who have not heard of Typescipt or Dart, it is yes definitely Python is great

Absolutely great video! Thanks. Thanks to the PyScript team, and associated, as well. This will be big down the road. And what an easy implementation.

Noobs use python. Coders love JavaScript.

if there is any apocalyptic for javascript any soon, i think would come by dart not pyscript

I can see this getting big , but def not replacing Java script

All code showing in page source...can you tell me something about it..

Meanwhile JavaScript developers be like.. "Let them come" 😌

This is game changing. If i had this 3 years ago, my clients project would have been finished in 1 month instead of 6.

I sure hope NOT. JS has its challenges, but it was born in the browser and has its natural habitat there. One of the most obvious reasons that Pyscript will have a tough time upending JS, is that Python is NOT a free-format language, whereas JS is a free-format language. You can type an arrow function in JS in one line. Try and do that in python! This also means that mini-fication is a challenge which the Python ecosystem is not going to make possible. What will happen is that these will co-exist as cousins in the web browser. Server-side the issue is not the same. I am not a Python developer, but the little I know is that it is good, but not angelic enough to replace JS. Lastly, years ago it was possible to use other scripting languages, not just Javascript in the browser in the script tag by specifying a different language name in the script tag. In the old days there were VBScript & JS, but also others (I cannot remember as this was more than 20 years ago), but I tested it and it worked for more than 2 languages. So JS has eliminated its main rival VBScript in a fight that has been going on for a few decades now.

Since web only know html, js, and css. I am pretty sure, py script is compiled to JavaScript at all

I love Python, but Python is not good for complicated applications. It's complexity when it comes to anything beyond simple synchronous scripting is a major stumbling block. I'm not saying Python is a bad language. It is really freaking great for research and scripting. And it's really freaking easy to learn, but it is not an adequate replacement for C, C++, C#, Java or JavaScript. Consider that even though Python is largely used to program machine learning, the actual core of machine learning libraries that do all the complex work are never actually built in Python themselves. It would be silly to build it in Python, it's simply too complex and too slow. It's much easier and more performant to build it in another language and then add a Python interface. Now consider a Python interpreter built in another interpreted high level language like JavaScript. This makes Python even less efficient and therefore even less desirable for an application like web development. If it's not already slow enough you are also losing the best part of JavaScript, the thing that makes it even usable at all for web development, asynchosity! Everything in JavaScript is event driven, Everything in Python is synchronous. This makes Python excellent at executing simple commands for research and hardware control, but an absolutely terrible choice for web development where nearly everything is event driven. TL;DR Python is a great choice for research and a poor choice for web development

Plz stop saying the end of JavaScript.

Soooo…… 0:12 0:37 0:43 1:06 1:19 1:37 1:45 1:50 1:52 1:55 2:03 2:11 2:20 2:38 2:49 2:56 3:00 3:10 3:13 3:21 3:27 3:41 3:51 3:52 3:54 3:59 4:11 4:24

This inst end of JS because pyscript is made with js.

ahh yes, much needed confusion for the front end, like we never had any

That's like PHP, it is going to be a MESS! xD

I'm a python developer. I really hope the python community can instead focus on those actual important issues such as adding a null-chaining operator or a a functioning type system.

You can also run C# in the browser thanks to Blazor and I'm pretty sure Java had an alternative as well.

Cool tool to build a more resilient Python focused application with, but NOT ending JavaScript in anyway.

Interesting but still skeptical. I wonder what performances could be achieved on real life application. Hope the web doen't take the wrong route once again

Call me back when you talk about events. A python code run by the press of buttons will surely help us ditch all those horrible JS scripts.

This is very cool, but what about security? If anyone can create shell inside your html like in jupyter, they probably also can get access to database by this methods. Hm..

The end of js? Best try of joke i have seen last 20 years

Can you show video of an OpenCV example of it?

So PyScript is JS? Then how can JS go away?

My question is... what can py do for me that java can't?

"...so for this we need NodeJS..." - lol))

Can we install python libraries on it? ?

The last time I did a python project, I had to implement most of my logic in C to make the performance bearable to users. I think python should just stick to data science. Wasm is here, I get it but with languages like GO, Rust, and C# on the web, it doesn't stand a chance for any serious web apps.

Imo i dont think python is good for other than scientific and ML stuffs

Sounds cool in theory, but python with it's significant whitespace being used in webpages would increase the bloat of the already bloated web. I imagine this would be good for small projects, but not large-scale web apps.

Ehmm.. this is not running python in the browser... this is just converting python syntax to javascript. Big difference, you will not get the performance advantage of python, in fact the opposite, it will require loads of extra processing. Sure you can now run python libraries, but that's pretty much it.

it compiles to js in order to run, right?

Every language starts by writing a compiler in another language, and then a compiler is created in that same language so that it no longer depends on another language. Pyscript may be written in Javascript, but in the future they sure are going to write the compiler in Python. And who knows, if browsers start supporting python there would be no need to use pyscript.js in the HTML. Currently the compiler is written in JS only because browsers understand JS, not Python. A DOM in Python would be interesting...

Finally, a new way to make the pages slower

😁 Really???... See all Python gangs getting excited. You really don't know much about the web, do you? You'll still have to write JS if you wanna build serious Web Apps. Pyscript just takes care of Logic. Tell me, how would you work with WebAPIs? The W3C has its implementation fully in JavaScript and that's what actually powers web applications, to be more precise, that's how the web communicates with the hardware.