The year was 1999 and the dot-com boom was going full-throttle. Companies everywhere were focused on building revolutionary applications using nothing but top-shelf hardware and state-of-the-art software tools. Developers everywhere were trying to figure out if they should play more foosball, more air hockey, or sit back down on their Aeron and write more code. Everywhere, that is, except Boise, Idaho. Or at least, Dave's small corner of it.

At Dave's company, developers worked at a solid pace, using reliable tools, for a stable industry. They were sub-sub-contractors on a giant project commissioned by the U.S. Navy to condense naval vessel documentation. Generally speaking, the complete documentation required for a modern warship-from the GPS calibration instructions to the giant 130-millimeter cannon repair guide-is measured in tons. By condensing the documentation into the electronic equivalent, they could not only save tremendous physical space, but they could make it much easier to navigate.

 

A Simple Plan

Dave's company's small piece of the pie involved writing a very specific application for a particular group of users. Their application needed to track who moved which box of classified documentation from where to where, and why. Given the very simple requirements, the entire application was assigned to Mark.

Mark believed in keeping things simple: he rarely left the command line, his text editor was notepad and his source repository was a few backup folders on a network drive. He didn't need or want more than that. It was a simple task that called for his simple methodologies.

As their app neared completion, a whole new set of requirements came in. Now, they had to add in security and logging. When Dave joined Mark's one-man team to help out with this, the current system of source control -- nothing -- became inconvenient for collaborating.

Dave suggested they set up a source-control repository, but Mark wanted to keep things simple. He devised a solution called the "source-control shingle."

 

Roofing and Revisions

The source-control shingle was literally that: an actual shingle from someone's house that somehow ended up in their office. It acted like a "talking stick," in that only he who possessed the shingle was allowed to edit the common libraries.

As time went on, the project's scope grew immensely. More and more developers came on board, and the source-control shingle was pushed to its limits. Despite not being in possession of the shingle, some developers broke protocol and edited the library files on the share drive. Finally, Mark agreed to use a simple source repository. He wanted to use the only source-control system that guaranteed file locks: Visual Source Safe.

Unfortunately, Source Safe was so painful to license and manage that Mark had no choice but to explore other options, some of which involved a piece of painted wood. After much arguing and cajoling, Mark agreed to try out open source CVS. Things went well for the first few days, but quickly took a turn for the worse.

"What happened to my code?" Mark asked. "I just did a CVS UPDATE and everything I wrote this morning is gone!"

"It's working fine for me," one of the developers replied.

"Same here," another joined in. "I just checked in my changes a few minutes ago, and they're still here."

"Wait," a third one questioned, "did you do an UPDATE before the COMMIT?"

"Did I what?" the second developer replied. "Oh. Crap."

Exasperated, Mark jumped. "That's it! We're going back to the shingle!"

Fortunately, some of the other developers managed to convince Mark to stick with CVS, at least for a little while longer. One of the developers even managed to enforce better source control practices using some server-side scripts. And despite Mark's constant reservations, they ended up staying with CVS throughout the project. But the whole while, Mark kept the shingle handy, just in case.


The Source Control Shingle was originally published in Alex's DevDisasters column in the April 15, 2008 issue of Redmond Developer News. RDN is a free magazine for influential readers and provides insight into Microsoft's plans, and news on the latest happenings and products in the Windows development marketplace.