In this post
When you first start playing a new game, the only thing you can build are Worker Residences. While your population grows, so does the amount of different buildings you can construct.
This happens at every Milestone. A Milestone in SteamWorld Build is tied to a certain population level. The first couple of Milestones are hit by reaching a specific amount of Workers.
Later on, that amount will be Engineers, Aristobots and Scientists.
All milestones and their unlocks
At every Milestone, new construction options become available. In this list, we'll note down every Milestone, the amount of population required to hit it and the buildings that reaching said Milestone unlocks.
| Milestone | Reached when | Unlocked in Overworld | Unlocked in Mine |
| 1 | 24 Workers (6 houses with general store access) | Warehouse, Forester, Lumbermill, Service Shop | |
| 2 | 70 Workers (12 houses with General Store and Service Shop access) | Cactus Farm | |
| 3 | 120 Workers (15 houses with General Store, Service Shop and Cactus Water supplied, or 20 houses without Cactus Water) | Charcoal Kiln and Train Station | |
| 4 | 200 Workers | Engineers | |
| 5 | 1 Engineer | Sand Sifting Factory, Glassblower, Moonshiner, Saloon | |
| 6 | 70 Engineers |
Repair of Abandoned Mineshaft (18 Engineers), Toolmaker, Surveyor Office, Paved Road |
Miners Quarters, Prospector Quarters |
| 7 | 120 Engineers | Pickaxe maker, Sheet metal factory, Spare Parts maker, | Scrap Extractor, Mechanic Quarters |
| 8 | 200 Engineers | Wash Service, Burger Meister | Water Purifier, Bridges, Surveillance factory with Radar machine, Dirty Water Extractor |
| 9 | 240 Engineers |
Aristobots |
|
| 10 | 1 Aristobot |
Waxing Shop, Polymerisation Plant |
|
| 11 | 80 Aristobots |
Sheriff’s Office, Armory, Diesel Plant, Hatmaker, Glass Wool Spinner, Oil Refinery |
Guard Quarters, Grenade Turret, Oil Extractor, Thumper |
| 12 | 120 Aristobots |
Fine Dining Restaurant, Steam Furnace, Carburizing Plant |
|
| 13 | 180 Aristobots |
Casino, Gunsmith, Black Powder Maker, Sulfur Distillery |
Flame Turret, Gas Extractor |
| 14 | 240 Aristobots |
Scientists |
|
| 15 | 1 Scientist |
Maglev Road, Retrofit Shop, University |
|
| 16 | 50 Scientists |
Lab Equipment Manufacturer, Sparkling Diesel Manufacturer |
Lightning Turret |
| 17 | 100 Scientists |
Art Studio, Oil Paint Factory, Large Stuff Collider |
Vectron Scrap Extractor |
| 18 | 150 Scientists |
Observatory |
|
| 19 | 240 Scientists |
Jetshroom Farm, Rocket Fuel Processing Plant |
|
A note on decorations
Reaching milestones also provides you with more decorations to spruce up your town.
But to be honest: there are so many different decorations to unlock, this list would be three times as vast. Also, improving the scenic side of town doesn't help with production nor bot happiness, so why bother?