Cut Your Debugging Time in Half: 4 Essential Tips For Effective Debugging

Debugging is a critical part of your role as a software developer, and it often comes with lots of stress and time pressure to fix urgent bugs.

I’ve spent years building software within multiple start-ups, and needless to say I’ve had to do my fair share of debugging.

It’s a stressful process —  especially when there’s an urgent, all-encompassing bug that’s affecting all of your customers from being able to use your application, and management is breathing down your neck looking for updates.

This pressure leads to many developers making a common mistake:

They debug without a plan.

To become a “rockstar developer”, it’s vital to avoid this pitfall and make sure that you debug your code effectively and systematically. Having a structured approach to your debugging process will help you find the source of bugs in your code quickly and with minimal effort.

Here are 4 helpful tips I’ve picked up that will help you cut your debugging time in half.

Tip 1: Use Logs Effectively

Picture your application as a busy airport and your logs as air traffic control.

Logs and log files monitor all incoming and outgoing operations, errors, and events. Just like air traffic control, they record everything, making them an incredibly rich source of information for developers.

An ‘Unexpected Token’ error may be cryptic on the surface, but coupled with your logs/log files, it can guide you directly to the source of the problem.

Consider an example where your application crashes when users try to save a form. You might spend hours trying to replicate the exact scenario in your development environment. However, if you dive into your log files, they might reveal that the error only occurs when a specific, unusual character is input into one of the form fields. Armed with this precise information, you can directly address the problem, saving you time and frustration.

Using logs effectively, however, is a delicate balancing act. Logs are only as useful as the information they contain.

Make sure you’re logging any important events and exceptions in your code. The more useful information your logs contain, the easier it will be to diagnose and fix issues when they arise.

However, you must also ensure that you aren’t generating excessive log messages, which can be costly in terms of storage and also cause too much noise, thus masking any real underlying issues.

To address this, make sure that you use different log levels effectively.

Consider using “debug” or “trace” level logs, which capture highly detailed information about your code’s execution. They are like the behind-the-scenes documentaries of your code, tracking the detailed context and each individual operation.

However, because these logs can generate a lot of data, they aren’t generally logged all the time. Typically, debug or trace logs are used in the development or testing stages, or temporarily enabled in production systems when you need to diagnose a complex issue.

In this way, you can maintain a balance between having useful logs and managing storage and noise effectively.

Tip 2: Use the Divide and Conquer Strategy

The Divide and Conquer strategy is a fundamental algorithmic technique for solving problems.

What does it involve? Simply breaking down a large problem into smaller, more manageable parts, and then combining the solutions for these parts to get the solution to the original problem.

This is a strategy you can employ in your debugging process too.

Instead of reading every single line of your function, start by splitting it into logical sections. These could be based on different tasks your function is performing or even different conditional or loop blocks.

Test these sections independently and see which one is throwing the error. For example, if you have a function performing a complex calculation, test the data input, then the calculation logic, then the data output separately.

Once you isolate the section containing the error, you can focus your efforts there. By breaking down your problem, you can save a significant amount of time and make the task of debugging much more manageable.

Make sure you make use of any error messages or stack traces that are thrown. These could provide clues to where the problem originates, giving you a head start on where to begin your Divide and Conquer strategy. By finding the problem area, you’ll not only save considerable time but also make your debugging task a whole lot more manageable.

Tip 3: Implement Rubber Duck Debugging

Who would have thought that a rubber duck (or any inanimate object, really) could be your trusty sidekick in debugging?

This is Rubber Duck Debugging, a method that might sound silly on the surface but can be a serious help in your coding journey.

Rubber Duck Debugging involves explaining your code, line by line, to a rubber duck. It’s as simple as that.

The purpose is to slow down, verbalise your logic and code, and in doing so, uncover any inconsistencies or mistakes in your code.

For example, while explaining your code, you might realise that an ‘if’ condition in your function is never being met because the preceding code always redirects the flow elsewhere.

This realisation might be hard to arrive at just by looking at the code, but when you explain your logic out loud, it becomes clear.

So, get talking.

Tip 4: Use Version Control to Your Advantage

Version Control systems are typically used for tracking changes in your code, collaborating with other developers, and saving versions of your work.

However, they can also be powerful debugging tools.

Did a new bug suddenly pop up after a recent series of code changes? Instead of manually combing through all the alterations, turn to Git.

Something like the git bisect command can help you identify the exact commit that introduced the bug.

Imagine you have a web application that was working fine yesterday but is crashing today. You’ve made ten commits between now and then. You could go through each commit, checking the changes, but that’s time-consuming.

Instead, you can simply use git bisect to automatically check the commits, quickly leading you to the problematic one.

In this way, your version control system not only helps keep track of your code changes but also helps you quickly zero in on the source of a bug.

And that’s all folks. Hopefully the 4 tips above will help you approach your debugging process in a way that is organised and controlled.

Remember, the key to efficient debugging is patience, systematic analysis, and making good use of the tools at your disposal.

Keep your cool, and work through the problem step-by-step.

Thanks very much for reading this — feel free to reach out if you have any questions or need further advice.