Programming Basics
More to discover ↗A practical guide to finding code that never finishes: recognize the symptoms, interrupt safely, check loop progress and recursion base cases, and add guards while debugging JavaScript.
Read article · 4 min↗An import error does not always mean a package is missing. Learn how to read the error, check paths and project settings, inspect dependencies, and verify a fix without making your project harder to reproduce.
Read article · 4 min↗An application can start locally but fail in a test, a new terminal, or a deployment because a required environment variable is missing. Learn how to recognize the symptoms, check the process environment without exposing secrets, and make configuration errors easier to diagnose.
Read article · 4 min↗A failing unit test tells you that an expectation and a result differ, but it does not tell you which one is wrong. Learn a repeatable way to reproduce the failure, read its evidence, check the expected behavior, and make a focused fix.
Read article · 4 min↗A JSON parsing error does not always mean the JSON itself is malformed. Learn how to inspect the actual API response, distinguish parsing failures from HTTP errors, and fix common problems such as HTML error pages, empty bodies, and invalid JSON syntax.
Read article · 4 min↗A practical checklist for finding out why a button click produces no response. Learn how to check the console, confirm your selector, inspect event listeners, and distinguish a missing click from a handler that fails later.
Read article · 4 min↗When a page looks wrong, changing CSS at random can create new problems. Learn a repeatable way to inspect an element, identify the rule or container causing the issue, test a fix in browser developer tools, and move the change back into your stylesheet.
Read article · 4 min↗A beginner-friendly workflow for finding out why a web page cannot load data, submit a form, or fetch a file. Learn how to capture the request, inspect its status and response, and decide what to check next.
Read article · 5 min↗A browser console error is a starting point, not a verdict. Learn how to reproduce the problem, read its message and stack trace, inspect the values involved, and verify that your fix addresses the cause.
Read article · 4 min↗An unhandled promise rejection can make an asynchronous failure easy to miss. Learn how to reproduce one, trace it through browser developer tools, and put error handling at the right boundary.
Read article · 4 min↗When JavaScript produces a surprising value, check the types involved before changing the calculation. Learn how to trace string and number conversions, inspect inputs, and fix common mistakes with explicit validation.
Read article · 4 min↗A practical debugging method for finding where a missing JavaScript value came from. Learn to read the error, inspect each step of a property path, trace assignments backward, and fix the cause rather than hiding the symptom.
Read article · 4 min↗A loop that runs once too many or once too few can quietly skip a value or read past the end of an array. Learn to spot off-by-one errors by checking index ranges, tracing small examples, and testing boundary cases.
Read article · 4 min↗When a program produces the wrong result, you do not have to inspect every line in order. Check the data near the middle of the process, decide which half contains the problem, and repeat. This guide shows how to use that approach with a small JavaScript example.
Read article · 4 min↗A minimal reproducible example strips a bug down to the smallest set of steps that still shows the problem. Learn how to capture the expected and actual results, remove unrelated code safely, and share an example someone else can run.
Read article · 4 min↗A beginner-friendly guide to pausing JavaScript, following its execution one line at a time, and checking variable values to find a loop bug.
Read article · 4 min↗Breakpoints are useful when you can pause a program and inspect its state. Logging is often better when a bug is intermittent, depends on timing, or happens somewhere you cannot easily attach a debugger. Learn how to choose between the two and write logs that help you trace a problem without creating new ones.
Read article · 4 min↗A program can fail before it starts, stop while it runs, or finish with the wrong answer. Learn how to recognize each kind of problem and choose a useful first debugging step.
Read article · 3 min↗A stack trace can look intimidating, but it follows a useful pattern. Learn how to identify the error, follow the path through your code, and turn the trace into a small debugging experiment.
Read article · 4 min↗A useful bug report gives another person a reliable path from a clean setup to the same failure. Learn what to include, how to build a minimal example, and how to separate what you observed from what you expected.
Read article · 4 min↗
