I made this build as [Yareli]'s "main" secondary weapon.

It's Forma expensive, it requires decent aim, probably it's not Steelpath worthy due to [Plinx] having low damage overall and this being a snowball build, other than that it will probably delete anything on normal content.

The main "theme" of the build is headshots, and the focus was to squeeze the most out of critical chance and critical damage as possible.

Hop onto Mergulina's back when fighting, quickly strafing left and right or forward and backward to keep the passive on.
Aim for headshots to build critical chance and damage, don't stop aiming to activate [Galvanized Crosshairs], once you start getting headshot kills, the damage ramps up into red crits easily.

[Primed Pistol Gambit] can be switched with [Creeping Bullseye] for 13% extra critical chance at the cost of 20% fire rate. Personally i don't think it's worth it.
You can probably switch the Riven out for one of the faction mods.

Why radiation damage? Because [Plinx] has innate fire and currently the only element for pistols that has a primed version mod is heat damage. Status is really low anyway, it's just there to increase the weapon damage a little bit. If the status procs however, it will make enemies shoot the target, so it's all good.

You can just use it with any frame, you'll just loose the 200% critical chance from Yareli's passive.
With Yareli, with damage fully built it kills a lvl180 Corrupted Heavy Gunner in 3-4 headshots.