Galois connections are super useful for static program analysis. In particular, for abstract interpretation. A great intro book is [1]. [1] Program Analysis –

Galois connections are super useful for static program analysis. In particular, for abstract interpretation. A great intro book is [1]. [1] Program Analysis – An Appetizer. https://arxiv.org/pdf/2012.10086 https://arxiv.org/pdf/2012.10086