ezyang’s blog

the arc of software bends towards understanding


Facebook support for BarnOwl

This one's for the MIT crowd. This morning, I finished my Facebook module for BarnOwl to my satisfaction (my satisfaction being asynchronous support for Facebook API calls, i.e. no more random freezing!) Getting it to run on Linerva was a bit involved, however, so here is the recipe. Setup a local CPAN installation using the […]

  • July 13, 2011

mod_fcgid 2.3 is broken (fixed in 2.3.6)

This is a post to get some Google juice for a problem that basically prevented Scripts from being able to cut over from Fedora 11 to Fedora 13. The cluster of new machines kept falling over from load, and we kept scratching our heads, wondering, “Why?” Turns out, the following commit broke mod_fcgid in a […]

  • November 10, 2010

Rapidly prototyping scripts in Haskell

I’ve been having some vicious fun over the weekend hacking up a little tool called MMR Hammer in Haskell. I won’t bore you with the vagaries of multimaster replication with Fedora Directory Server; instead, I want to talk about rapidly prototyping scripts in Haskell—programs that are characterized by a low amount of computation and a […]

  • October 18, 2010

Why being a sysadmin will help you do Science!

A complaint I once heard about SIPB is that it leans too much towards the system administration side: we proudly display the services we have deployed and neglect to talk very much about actually programming or conducting novel computer science research (despite the fact that we are very much programmers and some of us are […]

  • October 11, 2010

Tips for running a hackathon

A hackathon is an event, spanning from a day to a week, where hackers (not the cracking kind) get together to work on some common goals in concert. One use of a hackathon is to get some open-source contributors together and work hard on a particular feature: the combination of being together and being expected […]

  • October 1, 2010

Evolution of a Shared Web Host

Edward continues his spree of systems posts. Must be something in the Boston air. Yesterday, I gave a SIPB cluedump on the use and implementation of scripts.mit.edu, the shared host service that SIPB provides to the MIT community. I derive essentially all of my sysadmin experience points from helping maintain this service. Scripts is SIPB’s […]

  • September 15, 2010

Thinking about talk

This one's for the MIT crowd. I will unfortunately not be in Boston over IAP, so I won't be able to do a redux of the class I taught last year, Advanced Typeclasses in Haskell. However, since I will be in Boston for September, it might be a good time to do cluedump for SIPB […]

  • June 28, 2010

Haskell, The Hard Sell

Last week I talked about how we replaced a small C program with an equivalent piece of Haskell code. As much as I'd like to say that we deployed the code and there was much rejoicing and client side caching, the real story is a little more complicated than that. There were some really good […]

  • March 17, 2010

The Art of Posing a Problem

Last week, I was talking with Alexey Radul to figure out some interesting research problems that I can cut my teeth on. His PhD thesis discusses "propagation networks", which he argues is a more general substrate for computation than traditional methods. It's a long work, and it leaves open many questions, both theoretical and practical. […]

  • February 24, 2010