Tarn Adams

Co-creator of Dwarf Fortress who left a maths career to build it for 20 years

Tarn Adams at a glance

Known for: Dwarf Fortress
Based in: United Kingdom
Indie since: 2002
Active products: Dwarf Fortress

Facts checked 2026-10-22

About Tarn Adams

Tarn Adams is an American programmer and co-creator of Dwarf Fortress, the famously deep colony simulation. Born in Silverdale, Washington, he earned a maths degree at the University of Washington and a PhD from Stanford, then quit a postdoctoral position at Texas A&M in 2006 to make games full-time with his older brother Zach under the name Bay 12 Games.

The brothers started Dwarf Fortress in 2002 and released it free in 2006, living for more than 15 years on donations and Patreon support. The game's procedurally generated histories and emergent stories made it a cult classic and it was added to the Museum of Modern Art's collection in 2012.

In December 2022, partly to pay for family medical costs, Bay 12 released a premium version with graphics and music on Steam and itch.io, published by Kitfox Games. It sold 160,000 copies in its first day, earned $7.2 million in January 2023 alone, about half of which Adams said would go to taxes and expenses, and passed one million Steam sales by 2026. Adams moved to the United Kingdom in 2024 and continues to develop the game with his brother.

Products by Tarn Adams

Dwarf Fortress

store.steampowered.com

Colony and world simulation with procedurally generated history and emergent stories; free classic version plus a premium Steam edition.

1M+ Steam copies

Timeline

2002 — Started Dwarf Fortress with his brother Zach.
2006 — Left a maths postdoc at Texas A&M; released the first Dwarf Fortress alpha.
2012 — Dwarf Fortress was added to MoMA's video game collection.
2022 — Released the premium Steam version with Kitfox Games; 160,000 copies sold in 24 hours.
2023 — Bay 12 reported $7.2 million in revenue for January.
2024 — Moved to the United Kingdom.
2026 — Dwarf Fortress passed 1 million sales on Steam.

How Tarn builds

Simulate deeply and let stories emerge rather than scripting them.
Work on one lifelong project with patient, community support.
Keep a free version available to everyone.

Tarn Adams FAQ

Who is Tarn Adams?

Tarn Adams is an American programmer and co-creator of Dwarf Fortress, the famously deep colony simulation.

Who made Dwarf Fortress?

Dwarf Fortress was created by brothers Tarn and Zach Adams of Bay 12 Games; Tarn does the programming. They started it in 2002 and released the first version in 2006.

How much money did Dwarf Fortress make on Steam?

Bay 12 reported $7.2 million in revenue in January 2023, the first full month after the Steam launch; Tarn Adams said roughly half would go to taxes and business expenses.