seL4 design principles

seL4 has been our team's greatest achievement, but it didn't fall out of the sky: it was the result of 15 years of research, and has evolved further for the past 10 years.

From the beginning, the design of seL4 has been driven by a number of principles. But a recent internal discussion about some fine points of the spec (as well as some discussions with externals) reminded me that some of these principles are in the minds of the designers but not really documented. This can lead to people (internal as well as external to Trustworthy Systems) arguing for APIs that are not in the spirit of seL4. Hence I'll try to write up these principles.

Articles like these are rare.