New to QuantConnect: Debugging Now Live in the Algo Lab

We’re excited to announce that debugging is officially live in the Algo Lab. This new tool allows you to place breakpoints in your code, step through, and inspect variable values at different execution stages throughout your algorithm. The tool is accessible from the right side of the terminal in any open project.

To help you get familiar with the debugger, we’ve outlined four simple steps below:

  1. First, open the debugging tab and set breakpoints by clicking on the desired line number, which should become highlighted in grey.
  2. Next, you will see a “Watch” list. Enter the names of the variables you want to track here.
  3. Then, click “Backtest” and a new backtest with the heading [Debugging] will appear.
  4. Back in the terminal view, you can either click the play button to continue to the next breakpoint or the arrow for line-by-line execution. Click the stop button to exit the debug session.

Debugging for backtesting is provided free to all community users. We’re thrilled to offer this as the newest addition to our platform and look forward to continue providing additional tools in the future to improve your development experience. As always — happy coding!


By: Jared Broad

Founder & CEO

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