Modern Python at the Large Synoptic Survey Telescope

TL;DR

This paper discusses the migration of the Large Synoptic Survey Telescope's software from Python 2 to Python 3, detailing the methodology, progress, and modernization efforts to ensure compatibility before Python 2's end-of-life.

Contribution

It presents a comprehensive migration methodology and reports on the progress of porting LSST's software to Python 3, ensuring future compatibility.

Findings

Majority of code migrated to Python 3

Successful modernization of codebase

Preparation for Python 2 end-of-life

Abstract

The LSST software systems make extensive use of Python, with almost all of it initially being developed solely in Python 2. Since LSST will be commissioned when Python 2 is end-of-lifed it is critical that we have all our code support Python 3 before commissioning begins. Over the past year we have made significant progress in migrating the bulk of the code from the Data Management system onto Python 3. This paper presents our migration methodology, and the current status of the port, with our eventual aim to be running completely on Python 3 by early 2018. We also discuss recent modernizations to our Python codebase.