Sarah Allen’s reflections on internet software and other topics

I’ve decided to join the first nReduce session which starts this coming Tues, June 5, for my startup Mightyverse.

When I first heard of it via twitter, I was intrigued, but I was also put off by a venturebeat article which identified one if its founders, Jacques Crocker, as a Rails demigod. Since I am pretty active in the Rails community and had never heard of the guy, I was pretty skeptical.

I caught up with Jacques and co-founder Joe Mellin at a pre-launch gathering in San Francisco on Thursday. Jacques claimed the “demigod” title was made up by the press, and seems a genuine down-to-earth guy. When I arrived there were just 4-5 people sitting around a table, and it was clear that the nReduce guys didn’t expect more than 8 or 10. Pretty soon, it was a standing-room-only crowd with a lively group of entrepreneurs.

I got the chance to talk to both Jacque and Joe and hear their stories. I wondered how and why they were doing this thing. nReduce accepts all startups, they give you no money and take no equity. On Thursday they had over 300 startups signed up, with 83 in SF, today I see 500+ on their website.

Jacque decided to create nReduce after his startup was rejected from YCombinator and he wanted to create that kind of environment for himself. The YCombinator program is attractive for more than the insider-track to investor intros — people liken it to going to college, where you learn as much from your peer group as from your professors. And after graduation, your peers become an important network through your career. Jacque will be participating in the program himself.

I completely agree that for an early-stage startup, execution is tough enough. I love the idea that getting into the program should have no barriers, but staying in it should be tough — mirroring what is the real-world startup experience. Jacque told me he wanted to create a YCombinator-like experience, but for everyone. The deal is that anyone can join, but you need to ship every week. If you don’t ship two weeks in a row, you are dropped from the program.

Joe Mellin, who is building the nReduce web app himself, gave me some insights about how it works. Tuesday nights there will be both virtual and in-person meetings, for the cities where there are enough teams. Tuesday will have presentations to inspire the startups and the chance to demo to each other. On Wednesday, Teams will submit a description of what they shipped the previous week, along with a video, screencast or some evidence of their progress. There’s no incentive to submit something lame, since the goal is to be able to show prospective investors your ability to execute. At the end of 12 weeks, participating startups will have a 3rd party record of their progress. Since one of the key questions investors have is whether a new team can execute, the nReduce theory is that this will save time for investors as well as providing support and structure for startups. It feels like a 12 step program meets survivor. They are seeking sponsors and it seems like a great way for startups and big companies alike to get in front of a vibrant tech crowd — whether these particular startups succeed or fail, these entrepreneurs will be making great things happen in the tech world for years to come.

At the event on Thursday, I met a wide range of startup founders — two companies had just started 2 or 3 weeks ago, some still had their day jobs, one had recently graduated from another accelerator and had just signed their first customer. I love the diversity of experience represented in the group and look forward to seeing what Jacque, Joe and their team cook up for the Tuesday night kick-off.

Jeff Casimir believes he can train anyone with the passion and will to learn to be a professional software developer. He goes so far as to say if you don’t make it (and you are really working at it), he’ll consider it a personal failure if you don’t. Also, he’s partnered with LivingSocial who is eager to hire graduates of the program, paying you to learn whether or not you qualify for a job at the end.

I interviewed Jeff yesterday and posted an article about the Washington DC Hungry Academy program on the RailsBridge Open Workshops blog. I’m skeptical that you can got from “I’ve never coded” to writing production code on a web app like Living Social in 5 months, but if you have a passion to learn, go for it. At worst case, you’ll get some great training and experience and be on your way to becoming a software developer.

Jeff is a dedicated and imaginative teacher who has taught middle and high school before starting his business training software developers. I don’t doubt his skill and am eager to see what happens with the program. I believe that people need a lot of experience writing a lot of code before they would be ready for a typical job. Of course, I also believe that there are a wide variety of code writing projects in any software company. I’m sure that Living Social has quite a bit of code that needs to be written. My guess is that they plan to find starter projects for less experienced developers, if the folks who finish the program show that they are good learners. In any great software development class, you write quite a bit of code, so Jeff and other program mentors from LivingSocial will get a chance to see how people approach new challenges, ask good questions, work through problems and write code. As software developers, we are always learning new tools, frameworks and languages, and whole new patterns of development as the hardware underneath us radically changes in capability and the people who use our software change how they use it and what they want to do.

If you are in the DC area, or willing to move there for 5 months, and think you want to become a software developer or simply switch from building desktop apps or servlets to writing web apps in Ruby on Rails, I strongly suggest you check this out.

I’m thrilled to be part of the Women 2.0 Startup Weekend Documentary: Start Something.  Filmed as a student project with San Francisco State University’s Digital Video Intensive program, Start Something follows three groups of entrepreneurs as they navigate Startup Weekend, a three day event where entrepreneurs come together to share ideas, form teams and launch startups.

Produced by Dave Kochbeck, directed by Doug Latimer, and edited by Joseph McDonald, this film captures the excitement, frustration and serendipity of the startup experience which is the essence of Startup Weekend. In these 54-hour events, developers, coders, designers, marketers, product managers and startup enthusiasts come together to share ideas, form teams, build products, and create startups! While most startups created at these weekend events don’t continue, the people at the events often go on to create or join other startup companies — or take their startup skills to fuel innovation in their day jobs.

Many thanks to the Kaufman Foundation, the Startup Weekend crew, and all the prospective entrepreneurs who show up.

Goal: set up a minecraft server using free EC2 account from OSX
[update: FAIL -- game play doesn't work on a micro instance, if we want to use EC2 it looks like we need to use at least a small one. so be careful to adjust the steps below to pick a small instance if you want to play.]

I learned that there are a lot of minecraft server implementations. I decided to use Craftbukkit server largely because I saw it referenced from a RubyConf talk by Tom Enebo — might be fun to mod it someday :)

I pieced together information from some helpful tutorials from Ubuntu and Robert Sosinski.

1. Sign-up for an AWS account (1 year free for new AWS accounts, but you need a credit card)
2. Go to AWS Management Console
3. Create a Private Key
   • Select EC2 tab, click on “0 Key Pairs” on the right side
   • name it ec2.pem (or anything you want, but I’ll use ec2 in the rest of this tutorial)
   • save it to ~/.ec2/ec2.pem
4. Create a Certificate
   • Under your name in the top right corner, select “Security Credentials”
   • Download the private key and certificate and save them in ~/.ec2
5. Make your credential files private.  In your local terminal, type:
   • cd ~/.ec2
   • chmod go-rwx ~/.ec2/*.pem
6. Download EC2 API Tools
   • Unzip the Amazon EC2 Command-Line Tools
   • Move both the bin and lib directory into your ~/.ec2 directory
7. Your ~/.ec2 directory should have:
   • The cert-xxxxxxx.pem file
   • The pk-xxxxxxx.pem file
   • The bin directory
   • The lib directory
   • ec2.pem
8. Set up EC2 Command-line Tools
   • Put the following into your ~/.bash_profile:
     # Setup Amazon EC2 Command-Line Tools
export EC2_HOME=~/.ec2
export PATH=$PATH:$EC2_HOME/bin
export EC2_PRIVATE_KEY=`ls $EC2_HOME/pk-*.pem`
export EC2_CERT=`ls $EC2_HOME/cert-*.pem`
export JAVA_HOME=/System/Library/Frameworks/JavaVM.framework/Home/
   • On the command-line, type:
     source ~/.bash_profile
9. Startup a server
   • [Update] We want to be careful to choose an AMI that works with the micro instance, which is what we get for free.  Ubuntu takes up too much disk space by default to fit into a micro instance, so you need to use one of the micro Ubuntu AMIs they created for this purpose.  I’m going to use Maverick 10-10 — it’s the most recent version that has a micro version.
   • [Update] I picked one in us-east, since that’s where Amazon started my account by default and it seems that it needs to be in the same region matching the one set for my key:
     ec2-run-instances ami-cf33fea6 –instance-type t1.micro –region us-east-1 –key ec2
   • check to see if it is running, by typing:
     ec2-describe-instances
   • make a note of your hostname!  It should look something like:

   ec2-###-##-##-##.compute-1.amazonaws.com

10. Open relevant ports (22 for ssh, 80 for http, 25565 for minecraft):
ec2-authorize default -p 22
ec2-authorize default -p 80
ec2-authorize default -p 25565

11. ssh into your new instance
    ssh -i ec2.pem ubuntu@ec2-###-##-##-##.compute-1.amazonaws.com
12. Install Java (nice Ubuntu instructions)
    Note: to accept the license, use tab to get to the OK “button” then hit return, then arrow to get to “Yes” and hit return again.
    To verify installation:
    $ java -version
    java version “1.6.0_26″
    Java(TM) SE Runtime Environment (build 1.6.0_26-b03)
    Java HotSpot(TM) Client VM (build 20.1-b02, mixed mode, sharing)
13. See this tutorial for setting up minecraft, but if you are playing with the Minecraft 1.0 client (at least of today) you’ll need to install a dev build which you can find on the ci server. I found that I needed to run the server, stop it and run it again to get it to start without errors.
    • get the latest dev build (I’m running 1502):
      

      wget http://ci.bukkit.org/job/dev-CraftBukkit/lastSuccessfulBuild/artifact/target/craftbukkit-1.0.0-SNAPSHOT.jar
      

    • create a file called “start.sh” with the following contents:
      

      #!/bin/sh
      java -Xmx613M -Xincgc -jar craftbukkit-1.0.0-SNAPSHOT.jar
      

    • run the server in screen:

      screen
      ./start.sh
      

[Update] By tweaking the memory allocation, we can get it to work (most of the time) with a single player. I found that I can raise the memory allocation for java and use virtual memory, but that it sometimes maxes out the CPU.

Here’s the setting where the game couldn’t be failed (couldn’t fight monsters or build things):

#!/bin/sh
java -Xmx613M -Xincgc -jar craftbukkit-1.0.0-SNAPSHOT.jar

$top
  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
 1642 ubuntu    20   0  978m 300m  10m S 12.3 50.7 100:44.96 java

Note:
VIRT – 978M of virtual memory
RES – 300m resident (physical) memory

---

With this it sometimes works:

#!/bin/sh
java -Xmx1024M -Xincgc -jar craftbukkit-1.0.0-SNAPSHOT.jar

 2829 ubuntu    20   0 1336m 271m  10m S 14.0 45.8   0:18.76 java

---

With this works almost all the time (but we’ve only tested one player):

#!/bin/sh
java -Xmx2048M -Xincgc -jar craftbukkit-1.0.0-SNAPSHOT.jar

  PID USER      PR  NI  VIRT  RES  SHR S %CPU %MEM    TIME+  COMMAND
 2893 ubuntu    20   0 2499m 341m  10m S 99.8 57.6   0:27.68 java                                                                     

 2893 ubuntu    20   0 2499m 341m  10m S 18.2 57.7   1:27.30 java                     

when the CPU maxes out, I see this in the game console:
22:39:19 [WARNING] Can't keep up! Did the system time change, or is the server overloaded?

I’m coding again in native Objective-C coding for iOS with the lovely XCode.  It has been a while so I’ve been reading up on debugging tricks.  Sadly, it still feels a bit like debugging in Macsbug in 1990…

The graphical display of object values is fairly useless, but in gdb, we can use the po command to get a pretty printing of the object if it comes with a built in description (for details see nice writeup from cocoa with love).

For our own objects, we can define a debugDescription method. For example, if I have a Thing class which is a subclass of NSObject and just has a title and subtitle:

@implementation Thing

@synthesize title;
@synthesize subtitle;

- (NSString *)debugDescription { return [NSString stringWithFormat:@"title: %@\n subtitle: %@", title, subtitle]; }

@end

Then if I find myself at a breakpoint with an instance of Thing in scope, called “thing”:

(gdb) po thing
title: Another
subtitle: Another example

Or if I have an array of Thing instances, called “things”:

(gdb) po things
<__NSArrayM 0x6a157a0>(
title: Basic
subtitle: My Thing,
title: Something
subtitle: Example of something,
title: Another
subtitle: Another example
)

iphonedevelopertips illustrates this nicely in more detail with the description method which will do the same thing for any subclass of NSObject.

Note: print-object actually calls the debugDescription method of the specified object. NSObject implements this method by calling through to the description method. Thus, by default, an object’s debug description is the same as its description. However, you can override debugDescription if you want to decouple these; many Cocoa objects do this. (via Apple Tech Note 2124)

Update: LLVM Debugger sucks less

If you choose the LLVM Debugger, instead of gdb, you can see properties on an object without defining a description or debugDescription method:

(lldb) po thing
(Thing *) $8 = 0x06a487d0 
(lldb) po thing.title
(NSString *) $9 = 0x00005984 Another
(lldb) po thing.subtitle
(NSString *) $10 = 0x00005994 Another example

…but still no love for Arrays:

(lldb) po things
(NSMutableArray *) $11 = 0x06a0b6a0 <__NSArrayM 0x6a0b6a0>(
,
,

)

…just for fun, let’s see how to look at a property of the first object in an array:

(lldb) po [things objectAtIndex:0]
(id) $12 = 0x06a44d20 
(lldb) po [things objectAtIndex:0].title
error: warning: instance method '-objectAtIndex:' not found (return type defaults to 'id')
error: property 'title' not found on object of type 'id'
error: 1 errors parsing expression
(lldb) po (Thing*)[things objectAtIndex:0].title
error: warning: instance method '-objectAtIndex:' not found (return type defaults to 'id')
error: property 'title' not found on object of type 'id'
error: 1 errors parsing expression
(lldb) po ((Thing*)[things objectAtIndex:0]).title
(NSString *) $14 = 0x00005944 Basic
(lldb) po [[things objectAtIndex:0] valueForKey:@"title"]
(id) $15 = 0x00005944 Basic

Whew!