Experiencing slow startup times on a platform like Render.com can be frustrating as it may delay application deployment and negatively impact user experience. Slow startups could result from several issues, including but not limited to, inefficient code, large application size, network latency, or excessive temporary or build files.

Cleaning up temporary build files is indeed one of the potential solutions to this problem. Here’s why and how it could help:
Disk Space Management: Temporary build files, such as intermediate build artifacts, caches, and other temporary files that aren’t necessary for the production process, can accumulate over time, taking up valuable disk space. This accumulation can lead to slower read/write speeds, ultimately affecting startup performance.
Build Optimization: Start by reviewing your build process. Ensure that only necessary files are being included in your production build. Use tools or flags to strip out unneeded parts, such as development dependencies, debug symbols, or redundant libraries.
Automated Cleanup: Implement automated cleanup scripts that can run as part of your deployment cycle. This can help to systematically remove unnecessary temporary files after each deployment to keep the environment clean and efficient.
Cache Cleansing: Reassess your use of caching. While caches can speed up application performance, outdated caches, or improper cache management, can lead to consistency issues and slow starts. Ensure caches are being refreshed appropriately.
Logging and Monitoring: Implement logging to understand more about what’s happening during startup. Monitoring can reveal if certain parts of your application are taking more time to initialize. This insight can help you optimize or adjust those parts for better performance.
Performance Profiling: Use profiling tools to analyze the startup sequence. This can help in identifying specific bottlenecks related to code execution or dependencies.

Cleaning up temporary build files is a good practice, but it’s essential to evaluate it as part of a broader optimization strategy. Paying attention to overall application efficiency, container or server resource utilization, and keeping the build environment optimized are critical steps towards ensuring that your application starts quickly and performs reliably on Render.com.