PyGXL is a bridge between Teradyne’s IG-XL test programming environment and the popular Python programming language. Teradyne introduced PyGXL in 2021, and several customer teams are now using it to streamline new product introductions at the ATE test stage by allowing them to leverage the Python programs written by Validation Engineering teams to more quickly bring up device tests on the Teradyne platform. This presentation will discuss best practices to smooth the transition between bench testing and ATE, including a Python program architecture that encapsulates the bench equipment hardware interface commands into one (or a few) file(s) with dedicated classes. This facilitates simply replacing them at ATE test with the equivalent interface classes that instead call IG-XL instruments. We will also detail a Python utility to print and datalog from Python to: (a) the immediate window (with bold and color for debug); (b) the test output window; or (c) the datalog. Another example shows how to setup an IG-XL breakpoint function that can be called from Python breakpoints, which allows users to stop the program flow from IG-XL without crashing the test program. PyGXL, and these hints and utilities, makes achieving bin 1 faster and easier.