# Step 11: Build Affected Projects
## Build Affected Apps
**Once again make a change to `todos.component.html`:**
```html
```
**Run `npm run affected:build -- --base=master`**
Nx will rebuild `todos` app. Why didn't it rebuild `ui`?
By default, Nx build libraries in the context of some application. You can change it if you mark a library as `publishable`.
## Affected:\*
You can run any target against the affected projects in the graph like this:
```bash
npm run affected -- --target=build --base=master
```
!!!!!
Run "npm run affected -- --target=invalid --base=master". What do you see?
!!!!!
No projects to run invalid
An error message saying that the "invalid" target is invalid