How much unity across different teams?

Our company builds several (Java) applications that loosely communicate with eachother via web services, remote EJB and occasionally via shared data in a DB.

Each of those applications are build and maintained by their own teams. 1 or 2 persons for the smaller apps, and almost 10 for the largest one. The total amount of developers is approximately 25 FTE.

One problem we're facing is that there are some big egos among the teams. Historically the team of the largest app has set up a code convention and general guide lines. For instance our IDE is Netbeans, we use Hg for SCM, build with Ant and emphasize to first use as much from Java EE as possible, if that doesn't suffice use an external library and only resort to writing something yourself as a last resort. Writing things like yet another logging framework, orm, cms or web framework is pretty much not allowed following these guide lines.

Now some of the smaller teams go against this and start using Eclipse, Git and Maven and have an approach of writing as much as possible themselves and only look at existing things if time is short or they 'just don't feel like writing it themselves'. Where the main team uses log4j, one of the smaller teams just started writing their own logging framework.

There have been talks going on about all teams adhering to the same standards, but these have been 'troublesome' at best.

Now the big question I'd like to ask: does it actually matter that different teams do things differently? As long as each seperate app implements its requirements开发者_如何学编程 and provides the agreed upon interfaces, should we really force everyone to use Hg, Ant, the same code conventions, etc etc?

There is not much harm in letting each team use the technologies that work best for them. In fact if you restrict teams to the "standard" way of doing things you'll stifle innovation and have bad morale.

But you don't want things to diverge too much. There a few things you can do to prevent libraries and tools getting out of hand. The first thing is to have regular rotation of each member through the teams to cross pollinate ideas. In this way the best ideas will spread through the teams.

You can also enforce a "rule of 3", which simply says it is ok to introduce a second library, tool, logging approach, whatever. But as soon as you want to introduce a 3rd one, you have to remove one of the first two. In other words it is ok to have 2 competing logging frameworks but if there are 3 logging frameworks, choose one to kill.

A 3rd idea is to let developers run regular presentations to the entire developer group to demonstrate the pros and cons of each idea or approach. Encourage lots of discussion and constructive criticism. The purpose is to try many things and let everyone find the best way as a group.

Finally, Management 3.0 talks a lot more in depth about how teams make decisions. Well worth the read.