I built an CRM&#x2F;CMS application where every single controller action call is event sourced.<p>The whole application lives in memory as a single object aggregate, which gets rebuilt on startup. I started off with writing json to the file system, moved into compressing and appending to a log file, and moved into using Azure cloud tables.<p>It&#x27;s awesomely fast to respond to requests (15ms), and to add new features, but you do get interesting new problems, e.g. along the way I had to:<p>- come up with a way of migrating events (as my storage formats changed as I improved my frameworks)
- find a good way to do fast full-text-search against in memory objects as I had no SQL or ElasticSearch infrastructure (ended up using Linq against in-memory Lucene RamDirectories)
- deal with concurrency issues in a fairly novel manner(as all users are acting against a single in-memory)<p>I&#x27;m hoping this architecture will start to become more popular - I think we are in need of a framework equivalent to Rails to take it mainstream.