Siege, n. — The act or process of surrounding and attacking a fortified place in such a way as to isolate it from help and supplies, for the purpose of lessening the resistance of the defenders and thereby making capture possible…

Twitter is laying waste to developers, but it isn’t doing so in an overt way. Instead of killing developers – or, at least, their apps – outright, the social network has placed a cap on the number of users that each application can have, the developer’s resources, if you will. We may not feel the full effects of this change for some time to come, but at least one symptom has cropped up today.

Tapbots, an application development duo that makes the popular Tweetbot suite of Twitter clients, has removed the public alpha of its Mac application. In a blog post explaining the change, developer Paul Haddad says that the alpha was closed to limit the number of tokens (see: users) allocated to people that may not purchase the full version of the software. “We wish we could continue on but we didn’t make the rules,” Haddad says in his post. “We just have to live with them.”

Haddad is referring to the changes that Twitter made to its API on August 16. The social network introduced a limit on how many users any particular application can claim, and has actively discouraged the creation of third-party Twitter clients. (Or, as Twitter may prefer for them to be called, “apps that fall into the upper-right quadrant.”) When we first covered Twitter’s API changes, Haddad was telling a different story.

“In the short term, nothing. From an API standpoint the changes required for v1.1 are trivial,” Haddad said. “Long term, we shouldn’t be in any risk of running out of spots under Twitter’s cap anytime soon.”

For his part, Haddad says in his post that Tapbots tried working with Twitter over the last few days to come to some form of understanding. “We’ve been working with Twitter over the last few days to try to work around this limit for the duration of the beta,” he says, “but have been unable to come up with a solution that was acceptable to them.” Which is what Twitter told developers to do, a handy way to keep gripes that may easily go public behind closed doors, lest Twitter change its mind and cut access anyway.

That’s the beauty of Twitter’s plan: There isn’t a single thing a developer can do to evade these rules. Twitter owns the pipes, and it owns the data inside the pipes, and if you want to get to that data you’re damned well going to use the pipe that they’ve selected for you. And, this way, Twitter can say that it has attempted to compromise with developers by allowing them to keep 100,000 users (or more, depending on where they were at when the cap was introduced).

As Sarah wrote about earlier, these “tokens” can become a genuine problem for a number of developers. I myself have authorized applications to use Twitter that I don’t ever remember using, and I’m not alone.

Unfortunately, I count against the maximum number of users that each of those applications can support. If Slices wants to expand beyond a certain point, it can’t. Neither can Twitterific, Tweetbot, or any of the other clients I’ve experimented with over the years. That isn’t a big deal in the scheme of things – I am but one token, after all – but the thing about singular items is that they tend to add up.

Switch gears from the siege metaphor for a moment. Think, instead, of a developer as an astronaut. Without fresh air – new users – the astronaut is likely to decay in space (or, at the very least, abandon his mission). Twitter hasn’t cut access to the oxygen tank off yet, but it’s squeezing ever harder.

[Image Credit: Wikipedia]