# Building Warp's Input - With Warp

Watch how a Warp designer uses Warp's own agent to locate, modify, and test a UI component change in a large Rust codebase.

*Speaker: Dave, Product Design Lead at Warp*

![YouTube video](https://i.ytimg.com/vi/ySzUj7kMZ64/sddefault.jpg)

### The Challenge

Redesigning the input was tricky because it’s the primary interface developers use all day, every day.  
Everyone had opinions — and expectations — about how it should look and behave.

So, Peter (a product designer on my team) and I iterated on multiple designs using Figma.

Once we landed on a version we liked, we shared it internally.  
Most people were excited, but engineering resources were stretched thin — focused on improving agent-mode quality and prepping the Agentic Development Environment.

So I thought: *“What if I just Warp it?”*

#### Step 1. Locating the Git Diff Chip Code

Inside the universal input, there’s a small Git Diff chip — it shows your current branch and open changes. It was one pixel too tall. That tiny visual bug drove me nuts, so I used Warp to find where it lived.

Warp searched across the entire codebase and found references inside:

-   `displaychip.rs`
-   Related render and configuration files

It used a combination of semantic search, code indexing, and traditional grep to pinpoint the exact implementation.

* * *

#### Step 2. Modifying the Font Size

Once Warp located the implementation, I asked it to reduce the font size by 1 pixel.

Warp automatically edited the relevant lines:

-   Found the current setting (`system_font_size - 1`)
-   Adjusted it to (`system_font_size - 2`)

I reviewed the diffs to confirm everything looked good.

* * *

#### Step 3. Building and Testing the Change

Next, I rebuilt the app using:

```
cargo run
```