Build
Stack tanks, engines and decouplers part by part. Mount boosters in symmetry, choose what each tank carries, and arrange the staging by dragging - then save the design for the next flight.
Mission: evacuate Høm
Every launch fuels the next.
Høm is dying and everyone has to leave. Design rockets part by part, fly them on real orbital mechanics, and build the supply chain that gets a whole world off the ground.
Demo
launch
launch
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days
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hrs
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min
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sec
- Altitude km
- —
- Orbital vel. m/s
- —
- Time to Ap h:m:s
- —
- Mission time h:m:s
- —
- From the first line of code to a playable demo
- 5 WKS
- Worlds in the system
- 21
- Parts to build with
- 35
- Lifted is 1 kg paid for
- 1 KG
Mission brief
A dying world. A crisis that follows you. One way out.
The homeworld is collapsing, and its people have to go - all of them. But what killed Høm travels with the evacuees, and every world they settle becomes the next one to empty.
Lifting mass off Høm is the hardest thing you will ever do, so every kilogram counts: the fuel you make off-world, the metal you refine on a moon, the depot you leave in orbit. Build enough of it and humanity builds a ship that leaves the system for good.
Fly
Real orbital mechanics, not a rail. Stage your way to orbit, read your apoapsis and periapsis live, warp time, plan transfers on the map and set down on another world.
Supply
A rocket is only the start. Survey, mine, refine and carry - and build the outposts and depots that turn every launch into fuel for the next one.
The supply chain
Lifting mass is everything.
Every structure costs its own mass in metal, and every kilogram of it has to come from somewhere. Bring the system to life, one launch at a time.
- 01
Survey
Scan worlds from orbit. Find the ice, ore and carbon worth landing on.
- 02
Mine
Set drills down on the deposit. Raw material starts piling up.
- 03
Refine
Turn ore into metal and ice into propellant, where it was dug.
- 04
Carry
Cargo holds weigh out or cube out. Every kilogram has to be lifted.
- 05
Build
Every structure costs its own mass in metal. Colonies, depots, refineries.
- 06
Fuel
Propellant made off-world is Δv you don't need to lift off Høm.
- 06 feeds 01 - every launch fuels the next
Under the hood
Dozens of ships. A trickle of compute.
Roll Authority runs on Unity DOTS, the data-oriented side of the engine. The whole system keeps flying while you work - and your machine barely notices.
- ECS
Lean data
Every craft, part and world is an entity - plain data packed tight, so the CPU streams straight through it instead of chasing objects round memory.
- BURST
Native speed
Trajectory prediction, orbit lines and background flight are compiled by Burst into native code tuned for your processor.
- JOBS
Every core
The fleet-wide searches - transfers, intercepts, who's near what - fan out across every core you've got.
- RAILS
No drift
Craft you aren't flying ride exact Keplerian orbits outside the physics world: no wobble, no drift, next to no cost - until you take the stick again.
- FUSE
One tank
Stack tank sections to the size the mission needs and they fuse into a single tank - one physics body, not a wobbly column of five.
Early accessReservations open
Back the build. Play it first on Steam.
Reserve a Steam key for Roll Authority early access today. It is delivered to your account the moment Steam issues our keys, with a one-click link to activate it.
- Steam key for early access
- Every early access update
- The full game at 1.0 - no upgrade fee
- Fully refundable until your key arrives
Our Steam page is purchased. Once Valve approves it, we upload the early access version there - and every regular update after it.
Early access
$19.95
Plus tax. Rises to $39.95 at full release. Windows, delivered as a Steam key.
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The manifest
Who's on board.
Everyone who has signed up, live. Early access makes you Launch Crew; give more and you're commissioned as an officer - and from Captain up, you're called out on the figure.
- Accounts
- 0
- Launch Crew
- 0
- Officers
- 0
- Raised
- $0
02.55
The manifest opens with the first sign-up.
Oct 8Oct 9Now
Flight board
No officers commissioned yet - the first Pilot's callsign goes up here.
Raised$0
Ranks are your roles on the Discord, by total contributed before tax.
See the ranks →Flight plan
Where it's headed.
- 0In development
Free demo
October 2026 · itch.io
The first flight. Build a rocket, reach orbit, and set down on Luna - free.
- 1Planned
Early access
Steam page purchased · date to be announced
The supply chain opens: everything you build off-world starts paying for the next launch.
- 2Planned
The evacuation
Early access updates
The crisis spreads world to world, and every settlement you build becomes the next one to empty.
- 3Planned
1.0 - Departure
Full release
The generational ship, the warp jump, and humanity's last launch from the system.
Community
Join mission control.
Devlogs, playtests, bug reports and launch-day chaos - the Discord is where the game gets built with the people who play it.
Join the Discord