Nuclear Design Bureau released on Steam on September 14, 2026 at $9.99, developed by Design Bureau KB-11, in Early Access.
VERIFIED Source: Steam store page (appid 4190240), checked 2026-09-17
News · nuclear-design-bureau · 2026-09-17
Nuclear Design Bureau: Hardcore Reactor-Physics Sandbox Out Now in EA at $9.99
Nuclear Design Bureau is out now in Early Access at $9.99: a hardcore engineering sandbox where you design, simulate and detonate nuclear devices.
Status is labeled honestly; nothing here is copied from other sites.
Direct answer
Facts below are verified against the sources listed; nothing here is copied from other sites.
Baseline date: 2026-09-17. Always confirm in-game for anything time-sensitive.
Key facts
What we checked
Each fact lists the source that supports it.
The loop is design, simulate, detonate, refine: receive a directive, build a device on a blueprint grid, then run full detonation physics in real time.
VERIFIED Source: Steam store page (appid 4190240), checked 2026-09-17
FAQ
Frequently asked questions
Is Nuclear Design Bureau a realistic simulator?
It models shockwaves, heat, radiation and chain reactions in real time and uses live k-effective readings, but the developer describes it as an open sandbox engineering game in active development, not certified software.
Is it playable in Early Access?
Yes - the current build is playable end to end with the full design-to-detonation loop, the criticality lab, sandbox mode and campaign directives.
What is the criticality lab?
A first-person room where you physically assemble the core and reflector and watch a lagging wall counter climb toward criticality, with radiation exposure affecting the operator.
How much is Nuclear Design Bureau?
$9.99 on Steam, in Early Access.
Details
The full picture
Written from verified facts; labels mark how strong each statement's evidence is.
What the game is
Nuclear Design Bureau is a hardcore sandbox engineering game released September 14, 2026 in Early Access at $9.99.
You play a junior engineer at the Kurchatov Institute: the State gives you a target and a warehouse full of dangerous materials, and some directives limit what you are allowed to use.
Your job is to build a device that does what the directive asks - then diagnose why it fizzled, failed or wasted material, and change it.
The criticality lab
Measurement is a first-person room, not a menu: set the core in its cradle, lower the beryllium reflector onto it, and watch the wall counter while live k-effective climbs toward one.
Push it too far and the dose lands on your hands rather than on a number - radiation exposure is shown on the operator instead of in a readout.
The design step then happens on a blueprint grid where you paint materials, build the primary, casing and supporting systems.
Simulation depth and Early Access status
Shockwaves, heat, radiation and chain-reaction behaviour are modelled in real time, with a Detonation Viewer that shows the blast as it unfolds.
The current Early Access build is playable end to end and includes the core loop (Design, Simulate, Detonate, Refine), the criticality lab, sandbox mode, campaign directives and save/load.
The developer states the campaign, physics and tools are being built in the open and will change based on what players build and where they get stuck - so expect balance and physics iteration (BOUNDED: official Steam description, checked 2026-09-17).
Coverage & items to verify
What you can use right now, and what must be re-checked before publishing or by the next update.
| Field | Ready now | To verify |
|---|---|---|
| Facts & sources | 2 verified fact(s), each with its source. | Re-check with the next data pull. |
| Update cadence | Baseline 2026-09-17. | Codes/news re-checked every 3–7 days, daily around events. |
Evidence boundary
Sources behind this page
store.steampowered.com/app/4190240
Opened and used as the reference for the facts above.
Open source ↗Labels: VERIFIED official source · BOUNDED attributable secondary source · COMMUNITY player report pending verification. Re-check time-sensitive data in-game.
Last checked: 2026-09-17Related
Keep reading
Next step