Nuclear Design Bureau

Nuclear Design Bureau

Early access since Sep 2026

Design. Simulate. Detonate. As a junior engineer at the Kurchatov Institute, you design atomic devices to satisfy the demands of the State. A hardcore physics game simulating hydrodynamics, neutron transport, and thermonuclear fusion.

77% positive · 390 reviews
Not yet
In early access, still in active development
High confidence
Active Development
Not yet
In early access, still in active development
High confidence
Active Development

Where to buy

Steam $9.99
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Evaluation

Nuclear Design Bureau entered Steam Early Access on September 14, 2026 — just three days before this assessment. The developer describes it as a game "built in the open," explicitly stating that the campaign, physics, and tools will change based on player feedback and what content players ask for. This is the developer's stated reason for choosing Early Access. Within the first two days of launch (September 16, 2026), the developer shipped two hotfix patches addressing bugs, shape rendering issues, directive text corrections, and adding new drawing tools — demonstrating active, hands-on engagement with the game immediately post-launch. The game is actively unfinished by the developer's own description, with the Early Access framework being the vehicle for its continued development.
Evidence
Developer explicitly states the game is in Early Access because the campaign, physics, and tools will change based on player feedback — the game is intentionally unfinished and evolving.
store metadata · Sep 14, 2026 source development ongoing
high
Hotfix patch shipped two days after launch addressing multiple bugs, directive issues, and adding new drawing tools (circle arc, rectangle trapezoid, guide tool).
news post · Sep 16, 2026 source development ongoing
medium

Media

Details

Publisher
Design Bureau KB-11
Achievements
11
Platform
Windows
Controller
—
Steam Deck
Unsupported
Players
Single-player

About this game

WARNING! THIS GAME IS IN EARLY ACCESS. IT IS BUGGY AND COMPUTE HEAVY. PLAYERS MAY FACE POTENTIAL BUGS, FREEZES, AND CRASHES.

WHILE THIS GAME UTILIZES WEBGPU and ELECTRON, LINUX/PROTON/MACOS ARE NOT OFFICIALLY SUPPORTED YET. 

I UNDERSTAND THAT THE AI GENERATED CONTENT IS UNAPPEALING AND AM HEAVILY FOCUSED ON ADDRESSING THIS ISSUE. 

THERE IS AN ACTIVE DISCORD COMMUNITY, PLEASE JOIN IF YOU'D LIKE TO PARTICIPATE IN ITS DEVELOPMENT. 

NUCLEAR DESIGN BUREAU is a hardcore sandbox engineering game where you design and test nuclear devices.

You are a junior engineer at the Kurchatov Institute. The State gives you a target and a warehouse full of dangerous materials. Some directives limit what you are allowed to use. Your job is to build a device that does what the directive asks.

This game is built in the open. The campaign, the physics and the tools change based on what players build, where they get stuck, and what they ask for. That is the whole reason it is in Early Access.

HOW IT WORKS

- Receive a directive: Technical requirements and constraints, with material limits on some jobs.

- Measure it by hand: The criticality lab is first person. Set the core in its cradle, lower the beryllium reflector onto it, and watch the counter on the wall while the live k estimate climbs toward one. Push it too far and the dose lands on your hands, not on a number.

- Design: Paint materials straight onto the blueprint grid. Build the primary, the casing, and the supporting systems.

- Simulate: Hit the red button and run full detonation physics in real time.

- Refine: If it fizzles, fails, or wastes material, work out why and change it.

CORE FEATURES

- Physics-Driven Simulation: Shockwaves, heat, radiation, and chain-reaction behavior are modeled in real time.

- Criticality Lab: A first person room where you handle the real parts. Live Monte Carlo k-effective, a wall counter that lags the way the instrument actually would, and radiation exposure that shows on the operator instead of in a readout.

- Detonation Viewer: Observe detonations as they unfold, with live visual feedback on blast behavior.

- Campaign Directives: Structured mission progression with technical goals and constraints.

- Sandbox Mode: Unlimited experimentation with full design freedom.

- Iterative Engineering Loop: Build, test, diagnose, and optimize.

EARLY ACCESS STATUS (CURRENT BUILD)

The current Early Access build is playable end to end and includes the core gameplay loop:

- Design -> Simulate -> Detonate -> Refine

- The criticality lab

- Sandbox mode

- Campaign directives

- Save/load systems with ongoing stability improvements

This is an active development build. Expect balance changes, physics work, and campaign iteration during Early Access.

EARLY ACCESS ROADMAP (SUBJECT TO CHANGE)

Physics and Simulation

- Refining the detonation viewer (better shockwaves, damage radius and thermal radiation modeling, destructible buildings and targets)

- Finer grid resolution for stronger PCs and GPUs

- More to do in the criticality lab

Campaign and Content

- Expanding the campaign with unique challenges

- Many more directives/missions

- Voiced campaign

- Additional bomb concepts (high-radiation designs, clean bombs, neutron bombs)

- More advanced materials

Presentation and Audio

- More music tracks

Community and Meta

- Public leaderboard

- Statistics on every campaign directive, so you can compare how efficient your design was against everyone else's

DEVELOPMENT APPROACH

Design. Simulate. Detonate.

Early Access is where this game gets shaped in public. What players build, where they get stuck, and what they ask for decides what gets worked on next. Most of the day to day happens on Discord.

"The atom is not a soldier, Comrade. It is a force of nature. We merely tell it where to go."

Last evaluated Sep 17, 2026
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