While Dominaria is definitely pushing for a mono color deck archetype, I have attempted to create a build for a Mono Blue deck that I think was last popularized by the Blue Devotion deck in Theros. The full initial deck list for the ‘Mono Blue Tempo’ after the cut:

Mono Blue Tempo Djinn

Creatures
4 Tempest Djinn
4 Torrential Gearhulk
2 Baral, Chief of Compliance
2 Glyph Keeper

Spells
4 Disallow
4 Syncopate
2 Essence Scatter
4 Glimmer of Genius
2 Entrancing Melody
2 Blink of an Eye
2 Search for Azcanta
2 Pull from Tomorrow
1 Precognition Field
1 Icy Manipulator

Lands
18 Islands
4 Memorial to Genius
2 Field of Ruin