The HTTP connection was kept alive for almost 9 hours by using Server Sent Events (SSE) to send periodic updates on the status of a long-running process. The process itself was kicked off in an asynchronous manner, with a backoff/retry mechanism to handle API rate limits and other potential errors. To mitigate issues with Heroku's aggressive closure of idle connections, another asynchronous method was added to drop "heartbeat" SSE messages at regular intervals. This approach allowed the long-running process to run in the background without presenting as idle, ensuring its completion without interruption. The use of SSE also provided a way for clients to receive updates on the process's progress in real-time.