Fitz's H40 Optimized Psyk - Melee Pskytzo
 Psyker Build - Warhammer 40k: Darktide 

They nerfed gun psyker with the inexplicable removal of Tranquility Through Slaughter, but thanks to the new efficiency in the tree, we get to use soulblaze items more easily, so this is my current proposal for melee psyker. Duelling Sword is equally, if not more valid, thanks to how soulblaze will interact with Uncanny Strikes, but Force Greatswords are cool and so are Tac Axes.

The Laspistols have unique pushes with practically infinite cleave, allowing you to push bursters through blobs of Crushers, but keep in mind that this generates 10% peril, so you can headpop if you use it at 100%. Besides that, since we're taking Kinetic Flayer, a single laspistol shot often 1-shots even the most annoying of ranged elites/specialists and they have surprisingly good DPS into Reapers and bosses. If you want the Recon Lasgun instead, you can also run that. Use the same blessings and perks. Just be aware that it's kind of dead in the water now.

As I mentioned, Kinetic Flayer has various key upsides for this build, but Assail would help you proc Malefic Momentum, so it's another option. A third, though in my opinion far worse option, is Smite with Charged Strike.

You CAN run a staff with this and the most likely candidate would be the Electrokinetic (EK) staff, but you'd probably be better off using a more specialized build for that instead.