Zero-downtime deployments

It’s a common pattern, an enterprise software solution has a body of code, managed by version control, verified by continuous integration and eventually delivered to some deployment system. If that were the whole picture things would be relatively straightforward. Tests pass? deploy it! Unfortunately there is often also a database in the mix. This complicates …

Continue reading ‘Zero-downtime deployments’ »

Deployment pipeline anti-patterns

It’s happened on most reasonable sized projects I have worked on. The benefits of test coverage an continuous integration are obvious and pay back immediately. But, somehow, as the project grows and diversifies, a point is reached where the complexity and run time of the CI process begins to slow down development rather than assist …

Continue reading ‘Deployment pipeline anti-patterns’ »

LiquiBase – a tool for managing database changes

No database schema or default dataset is ever perfect, things always change as software evolves. It can become tricky to ensure that each deployed version of a system gets the right database configuration. At present in our project we attach a growing list of “roll forward” and “roll backward” scripts to each project, and rely …

Continue reading ‘LiquiBase – a tool for managing database changes’ »

Chef – scriptable multi-machine deployment

I’m a strong believer that manual steps should be automated wherever possible. One of the areas of our current product which seems to require an inordinate amount of manual “faffing” is provisioning and deployment. Chef, a ruby system for distributing and automating just these kinds of tasks seems an interesting solution. Home – Chef – …

Continue reading ‘Chef – scriptable multi-machine deployment’ »

Amazon announces a cloud-based content-delivery service

The industry in which I work involves a fair amount of content delivery over HTTP. or at least it does when the rest of the system is in place to allow people to buy stuff. As such, we have a fair amount of operation and deployment issues around keeping this working. For each new customer …

Continue reading ‘Amazon announces a cloud-based content-delivery service’ »