This build is about fast, speedy, fluid movement in missions. You have the choice to either leave your teammates in your dust or give 'em a good kick to get through the mission faster! At this point, this is the only load out I use in quick pub contents even up to SP if your weapons are good enough.

Add-ons

Couple this with Amalgam Serration + Praedos with II - Drifting Grace(+20% Sprint/Slide) and IV - Evolved Ascension(+30% Parkour Velocity)

Firewalker replaces 1(or 4 if you prefer) for +25% speed. The status cleanser + extra damage are nice too!

Other, optional movement bonuses:
Amalgam Barrel Diffusion on secondary for the speedy rolls
Anti-Grav Array on a sentinel/robot to boost jump height
Dispatch Overdrive on melee for extra, time-limited zoom
Kavat's Grace is in the build in the place of Flow. Current in-game description is wrong, it prevents ALL hard landings. Use whichever you prefer!

(With the above, I get 2.05 total base sprint, which comes out to a 516% movement boost with Speed!) - Math is (1x2.05)(1+(0.75x2.67))-1)=5.16

Archon Shards

I went with 2 Crimson for STR, 2 Ambers for Parkour + Casting speed, 1 Azure for HP regeneration.
With 3 STR Taus @ 45% total, coupled with the 2.05 sprint, this build would be at about 585% movement boost with just Speed.

Gameplay

Keep Firewalker and Speed up at all times. Try to get in range of teammates to give them Speed. Use Speed to keep up the shieldgate-lite if needed. You can use 3/4 at your discretion, 3 is a powerful damage boost/damage negator, 4 is good for a little CC.

You have a lot of control with this build, so flying through maps(even tight hallway tilesets) is a breeze but takes practice. You can pick up shield so you don't get stopped by enemies(it knocks them down as you run at them), but you can also just jump over/go around them.

Reasoning for the mods

Sprint Speed is actually the best stat to boost to take advantage of Speed, so I prioritized that with Sprint Boost and Rush.

The next stat to influence Speed is Strength, which is where Umbral Intensify, Blind Rage, and Augur Secrets come into play. The high strength helps your teammates keep up with you, as they may not have the same Sprint bonuses.

Shock Trooper at 300% Strength is too good to pass up. Just make sure it doesn't mess up with the elements on your weapons, remember that it's as if you put an electricity mod at the end of your weapon mods. (The nonexistent slot to the right of [Shock Trooper]).

Kavat's Grace - Prevents any and all hard landings, great mod. Zenurik or Energize is highly recommended without [Flow].
Don't use Kavat if you don't want to, but this prevents the most speed loss compared to other techniques to avoid hard landings. Not necessary in the slightest, but great QoL.

Arcane Guardian and Adaptation are survivability mods that can keep you from dying in a split second in Axi/Requiem fissure.

Primed Sure Footed if you decide to use AoE weapons, or if you don't like being knocked around by enemies. You can replace this with a mod of your own choice if you don't use AoE or don't have PSF yet.
If you want a little more survivability, you can get rid of PSF, move Rush to the Exilus slot, and put in Umbral Vitality.

Alternatives:

You can use non-Umbral/Primed mod versions, it won't affect the build too much.

Arcanes:
I prefer using Molt Efficiency as I want as much duration as I can get(Speed @ 19.10s v 15.50s) , but you can switch it out. If you want more speed Arcane Phantasm can bring your speed boost, theoretically, to almost 700%! But really, you can go with whatever makes you happy. This also goes for Guardian, and if you want a more shield gating w/ dragon key approach, use Aegis/Barrier with [Brief Respite] and [Rolling Guard] instead of [Adaptation].

This is my personal build and recommendation for a fun [Volt] experience, feel free to mirror completely or switch out for mods that you prefer.

Changes:

Replaced [Flow] with [Kavat's Grace]. Recommended, but [Flow] is better for energy conservation. I could go hours avoiding heavy landings, but trust me when I say it's a huge QoL improvement.
Primed Flow for higher energy capacity to offset low efficiency. Duration mods, Primed Continuity and Molt Efficiency, are used so you're not constantly re-casting Speed. Be mindful to only cast when the timer is about to run out or when needed. The longer duration also allows you to have an easier time keeping everyone boosted. If you want to never worry about energy, use Zenurik or switch Molt Efficiency for Arcane Energize.

Replaced [Amar's Anguish] with [Shock Trooper]. Unfortunately makes the title clickbait without the +15% Sprint... sorry! (At 1.9 Sprint, 297% STR, fire walker, it's 538%...)
Amar's Anguish is used to eek out a little more sprint, but the Bullet Jump increase is too good to pass up as it will make fast movement more fluid overall. (+bonus of melee teleport)