Creating a Maintainable Software Ecosystem Jeremy D. Miller November 27th, 2007

Sharpen the Saw! “Give me six hours to chop down a tree and I will spend the first four sharpening the axe. ” - Abraham Lincoln

The 10X Development Ecosystem It’s the code, yes, but it’s also the ecosystem What’s the Ecosystem?  Source Control  Build scripts  Continuous Integration infrastructure  Test automation  Database scripts and migrations

Themes Eliminating Friction Go fast, go safe Knowing where things are Ratcheting up the Feedback Loops Favoring automation over formal processes

Story Wall – Start of the Iteration Not StartedIn ProgressTesting Customer Review Done, Done, Done Story #1 Story #2 Story #3 Story #4 Story #5 Story #6 Story #7 Story #8 Story #9 Story #10

Story Wall – Iteration Halfway Point Not StartedIn ProgressTesting Customer Review Done, Done, Done Story #1 Story #2 Story #3 Story #4 Story #5 Story #6 Story #7 Story #8 Story #9 Story #10

Dude, it worked on my box! You can’t work if you can’t run the system The build script should lay down the development environment Build script == environment documentation 3 rd Party tools and open source libraries in source control Propagate new environmental dependencies ASAP! Retrofit Legacy Code with automated build scripts README.txt

I grabbed the latest code, but it’s broken! Lean on Continuous Integration  Compile  Lay down the environment  Unit tests Clean Build Server It’s all about feedback

The Check-In Dance 1.Don’t check into or out of a broken build 2.Update your code from source control 3.Merge any conflicts 4.Run the build locally 5.If the build is successful, commit your changes 6.Monitor the build server for success or failure 7.If the build breaks, fix it! 8.Never leave a build broken overnight

Are you sure you have the right code? Single Source Point Tag successful builds Embed the build number in compiled assemblies NEVER build and deploy from a developer environment Repeatable, traceable builds Promote code by build number Communicate issues, fixes, and feature completion by build number Demo: Labeling builds with CruiseControl.Net

Right code, wrong database! Treat all database code as just more code DBA’s play by the same rules One database per developer and environment  Demo: “database.build” If it changes together, it builds together Propagating database changes must be reliable, easy, and friction free  Enable continuous design and incremental delivery  Synchronize development environments  Demo: Migrations

It’s a five minute fix… …but it’ll take a day to migrate the code You will make mistakes Cycle faster between development and testing Automate anything that moves Create deployment packages on successful Continuous Integration builds Use a no touch deployment to testing

Did it get installed correctly in test? Environment tests Demo: Self-testing configuration with StructureMap Synthetic transaction

What would it take for last minute changes to be safe? Comprehensive automated test coverage Feedback cycle Fast build, slow build  Demo: Cascading build Prerequisites for Test Automation  If the tests haven’t been run, how do you know your code still works?  Getting the latest code to the test environment  Watch for file collisions  Building a set of test data

My goodness, we’ve got a lot of code! Multiple source control repositories and builds Propagating dependent libraries  Manual or Automatic? Shared resources

Are you pointed at the right server? Demo: Configuration profiles with StructureMap

Sharpening the Saw “I don’t have time to sharpen my saw, I’m too busy chopping wood!” Balancing technical improvements versus new business features Make it easy to do the right thing No artificial process restrictions “We’ve just got to get the project out the door”

Last Thoughts Project automation is a team effort  Watch the Low Truck Number effect Use project automation as an enabler Automate anything repetitive Automate away friction Look to automate bookkeeping activities Feedback is everything  Frequent check-ins  Keep the build lean and mean  Run the automated tests frequently

Questions The Shade Tree Developer –