Making and hosting a web application just got a whole lot easier. Y Combinator’s AppJet has just launched a website where you can write and run hosted applications right in your browser. The system is currently pretty basic, but aims to add levels of sophistication in the coming year.
Using AppJet reminds me a lot of when I first learned programming through Lisp. Lisp has a simple syntax and processes your code on the fly, making it easy to modify and test code immediately. AppJet is similarly straight forward. Applications are programmed on a web based text editor in the very simple Javascript programming language. Javascript is used on both the server and client side. They’ve included several bundles of code libraries for databases and more importantly interfacing with the Facebook API.
To get your own application, all you have to do is type up your code and save. The application is then published to a unique URL (ex. hello-world.appjet.com) where it runs when anyone goes to the site. Other users can also view an application’s source code to learn and improve upon the original. I’ve embedded an example “message wall” application below.
Hosting other people’s code is tough business. Doing it efficiently requires a system that can dynamically allocate more or less computing resources to programs in response to demand, as well as security that effectively handles maliciously or foolishly programed code. You don’t want an infinite loop taking down the whole system.
To tackle these problems, AppJet has developed their own application virtualization system. The system allocates processor time to active apps and cuts off greedy applications after running an alloted number of compiled lines of code to pevent abuse. While the entire system is currently free, limitations on processing and storage space (10mb), leave an opportunity for paid plans.








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Someone cuss Mark’s last name. Any idea who wrote Facebook name?
Let me guess… Techcrunch…
That sounds very good
Welcome everything easier work
pretty much just a toy right now
I think you should put some spam protection in your message wall.
Sweet website though.
ps How could the word “boobs” (amond other truly inspired words) be the first that pops up in someone’s head when testing a comments/wall?
Not sure what is the point of this? If I want a server-side app I can always use ROR, ASP.NET,…. etc?!
The embedding reminds me of the iMacros shared macros feature, where you can embedded a (Javascript) macro in a link: http://del.icio.us/imacros/imacro
Of course, the main difference is that iMacros run client-side in the web browser whereas appjet runs on the server.
This is awesome! I waited for something like Appjet for a while
This is fantastic…last time I started a website it took me 3 times as long to set up the server as write the code. Probably will do my next one on Appjet. Hope it’s not too expensive, I pay $75 a month for a Rails Machine.
Well it’s a start. Will it go to what Zoho apps are currently doing? guess so
I’m actually building a similar application but hopefully much simpler and easier to use. Also it uses Python so you get all of the power of Python’s third party libraries such as image manipulation, PDF creation, etc.
Let me know what you think.
This is a smart business move…. the long tail of web apps is totally untapped because there is too much activation energy in setting up servers. AppJet even makes it free! I wonder for how long. Amazing technology here.
@Robzor Agree.
I’ve done the FaceBook app with Rails/EC2 thing, which was somewhat painful. This looks nice. Given, say, an indexable, relational datastore, I would definitely use this for most of my social app development in the near term.
Simple and quite useless apps.
PS: Nick, are you YC staff writer?
I’m really excited about what these guys are doing, especially with improving the ease of development and hosting of facebook apps. Hope to see some great examples come out of it to help the rest of us get going on fb apps.
what is Lisp? Where can I get it from? Does it process ajax?
I checked it out but soon quit when I couldn’t correct mistyped scripts with undefined functions - after the error the preview just ignored anything I typed into the editor. Then I saw the version number: 0.1. Alright …
@15: A lisp is mythological beast from ancient times, processing anything and consisting mainly of brackets.
@Barry Welch:
I haven’t used EC2 because I’ve heard it’s a total nightmare to get up and running. How long did it take you to set up EC2?
It’s interesting that all the server-side code on Appjet is Javascript; I do enough Javascript hacking in the browser that it might be good to use just one language instead of Ruby on the server / JS on the frontend.
This is pretty cool, I just made an app- http://notes.appjet.com
I don’t have any real programing expirence but I made that in like three hours :).
@Greg: I checked out Utility Mill and it looks impressive… the thing it’s lacking is the ability to create a standalone web app. I don’t want to just create web services to plug into other sites. If you work on that I’m sure UM will be successful.
This looks like the perfect tool for teaching people to program. Could this be the last hurdle in getting my girlfriend to try coding?
“very simple Javascript programming language” - hehe
@Robzor: how do you mean? Do you want UM to generate a CGI script you can host on your own site? Or did you have something else in mind? Feel free to drop me an email if you want to chat more.
Sweet.
Hot stuff! Its so damned hard for a casual developer to develop a website, deploy it, register the domain, etc. This makes it so easy! Hell, I don’t even like doing it myself and end up having websites within websites…
Being able to view source and clone an app… good stuff.
this is just useless for any serious enterprise applications. It does not cover security, session handling and all that. Useless 1st year college project.
there are just too many rubbish applications out there. Try the apache.org site for serious open-source stuff rather than these toys.
I think AppJet may have flown over sky’s head =)
This is great stuff… I look forward to writing all my future web apps with AppJet!
All are being rendered obsolete by MS even as we speak!
http://fakesteveballmer.blogspot.com
Seems like a nifty tool for prototyping and RAD. Provision for Facebook apps is quite useful as well.
And it can bind well with Feedity ( http://www.feedity.com ) to scrape web content, build custom RSS/XML web feeds, and then use the content in AppJet apps.
It just works.
In a couple of hours I developed a sample server side data store for my client side wiki experiment.
This is a very simple yet powerful idea — every developer can now be “in the Cloud” — dead simple.
http://virteal.appjet.com/wiki
Trivial software. First year high school project. My grandma could code this. Stop reinventing the wheel!