Calendar migration for 100k+ users

In this project, I collaborated with a prominent British telecommunication provider that sought to transition its six-figure user base to an advanced messaging platform. The primary objective was to migrate seamlessly to the new platform, encompassing essential functionalities such as address book, calendar, and mail solutions, without causing any downtime.

Taking charge of the calendar migration aspect within the broader user migration initiative, my responsibilities were essential in ensuring a smooth transition. Utilising my expertise, I employed Python and Celery to craft migration workflows that operated seamlessly in the background.

The calendar migration process was carefully divided into two distinct phases. First, I orchestrated the transformation of the source model, residing in relational databases, into an intermediate model represented by iCal files. Subsequently, the second phase involved translating these iCal files into the target model. The strategic separation of these steps aimed at creating a modular structure, facilitating the reuse of the second phase for subsequent calendar migrations for other customers.

One of the project’s essential quality aspect was the thorough testing applied to the entire calendar migration process. This rigorous testing approach allowed for the swift identification and rectification of any issues. Consequently, a failing calendar migration could be easily reproduced, fixed, tested, and rerun, ensuring a robust and reliable migration process.

The successful migration to the new platform had a tangible impact on cost savings for the client, as it enabled them to retire legacy systems while maintaining operational efficiency. This project exemplified my proficiency in managing complex migration tasks, employing Python and Celery to develop robust workflows, and implementing thorough testing strategies to guarantee a seamless transition for the client.