Levi, a top programmer, travels to a magical world and is shocked to discover that magic is actually an underlying code full of loopholes! From conquering the village chief with Excel to crushing the Demon King's army with agile development, he established a "code empire" and cultivated AI "little codes" into gods. When humanity and divinity conflict and nothingness engulfs the world, he chooses to use himself as a patch to find the original "Hello World" with a grand debug. This is a hard-core fantasy epic in which code reconstructs the world and bugs lead directly to heaven.