Yoda Response: Certainly. One complex coding problem I encountered involved SSL pinning for secure API calls. Initially, we hard-coded the SSL certificate in the mobile app. However, we faced an issue when the domain's certificate was updated, causing the app to stop working because it still held the old certificate.

To address this, we realized that forcing users to update the app every time the certificate changed was not a viable solution. Instead, we devised a dynamic approach to fetch the certificate data from our backend server.

Here's how we approached the problem:

1. **Initial Setup**: We initially hard-coded the certificate in the app, which worked until the certificate was updated on the server side.

2. **Problem Identification**: We identified that the app would stop working whenever the server's certificate was updated, as it still relied on the old certificate.

3. **Dynamic Fetching Mechanism**: To solve this, we implemented a mechanism where the app would dynamically fetch the latest certificate from the backend server. We introduced versioning for the certificate data. Whenever the server updated the certificate, it also updated the version number.

4. **API Call for Certificate**: The app was modified to make an API call to the backend server to check the certificate version. If the version had changed, the app would fetch the new certificate and replace the old one.

5. **Implementation**: We removed the hard-coded certificate and implemented logic to download and store the new certificate dynamically. This ensured that the app always had the latest certificate without requiring a manual update from the user.

This solution provided a seamless and uninterrupted service for users, eliminating the need for frequent app updates and ensuring that the app always used the correct certificate for secure API calls.