Recently, I've been working with a client as part of a major platform change they're making. It's the third time I've been involved with a big architecture shift, each at a different company, and each larger than the last, but there seem to be some observations that apply whether you've got five servers or five hundred.

1. Business carries on

It can be easy to get somewhat myopic when in the middle of an exciting architectural change. Major platform transitions tend to occur when there has been a realisation high up in the company that something needs to be done, so teams often have a fair degree of scope and freedom. However, it is even more likely that other parts of the business will need to continue to work on the existing system. If a new feature is required then it's going to get developed, even if that involves duplicating, or worse conflicting, with work that's being done as part of the platform change.