Space of Cauchy filters
This is essentially the completion of a uniform space. The embeddings are the neighbourhood filters. This space is not minimal, the separated uniform space (i.e. quotiented on the intersection of all entourages) is necessary for this.
Embedding of α into its completion
Hausdorff completion of α
Automatic coercion from α to its completion. Not always injective.
"Extension" to the completion. It is defined for any map f but returns an arbitrary constant value if f is not uniformly continuous
Completion functor acting on morphisms