Reduce build time for Fusion

**Motivation**
Fusion build time is too long (few minutes) and this affects the developer productivity.

**Acceptance criteria**
1. Build time is reduced to under a minutes for both local and production builds.

**API changes**
N/A

**Mockups**
N/A

The issue provides no file, test, or build entry point for Fusion. Start by locating the Fusion build configuration and measuring both local and production builds; done means each completes in under one minute.

Written by the indexing model from the issue text.