Actually, I've always been somewhat reluctant to tackle this topic because the problem is both too fundamental and too broad. I've never been confident about covering this topic well. However, due to some well-known circumstances, I feel I should at least share some of my views and insights from discussions with friends.

Whether frontend or backend, environment variables are a very important concept that can provide context to your programs, such as whether you're in a development or production mode, whether your development environment is local or remote, or what backend URL you're deploying to, some SaaS keys, these are all problems that environment variables can help solve. The reason this topic is difficult to discuss is that different projects may have different best practices, or there might not even exist a so-called "the best practice". I've personally witnessed two Senior Frontend Developers arguing over this issue. Moreover, you must deeply understand a project to know what constitutes an appropriate practice.

As some of my Twitter followers may know, I recently experienced some mental health challenges due to various factors, one of which was my experience with Flutter Web. This might surprise some of my friends, given that I'm known as a Flutter enthusiast.

To be honest, I remain a passionate advocate for Flutter's mobile development capabilities. However, I cannot endorse Flutter Web in any capacity, and I will explain my reasoning throughout this article.

As we all know, JavaScript is a beautiful, elegant, and well-designed language. Brendan Eich spent much of his life designing it. Thanks to that, we have such an intuitive language:

NaN !== NaN // true
0.1 + 0.2 // 0.30000000000000004
1 < 2 < 3 // true
3 > 2 > 1 // false 
[] + [] // ""
{} + {} // "[object Object][object Object]"
[] + {} // "[object Object]"
{} + [] // 0

We had a knowledge-sharing slack-off session today, and someone shared a question about the beauty of the language's syntax. It reminded me of my previous job in China. Almost all Chinese companies like using these elegant syntax and principles as interview questions. When I think about the most memorable question I prepared, it has to be this one:

What is the result of Math.max() < Math.min()? why?

With the size growing of the project, an increasing number of logs are written. It is tough to find out helpful detail within hundreds of irrelative logs. Although JavaScript is awkward in many places, it has very powerful tools and ecosystems to debug when it is running on the browser.

Due to the high amount of wordle spam from my friend, I need some tools to reduce their interest of play Wordle. During these months, I developed a website to provide hints of possible worlds and continue to finetune the algorithm. Then, the limitation of the website is found, so I turn to build a browser extension.

In a previous interview, a debug question causes me to deep consideration. What is the GC strategy of JavaScript when we are using setTimeout and setInterval? What happen if we did not clear the timer before releasing the timer of setTimeout?

Lazy loading is a useful technique that can delay loading non-essential content in an application until it is needed. It can reduce the bundle size and increase the loading performance. However, there are many implications and solutions of that in history.

When we are completing the question on leetcode or developing a complicated project, iteration is a useful syntax to traverse complex data structures.

The Array is a common data structure in computer science, the majority of languages provide while and for-loop to iterate the array. Moreover, High-level programming languages always provide some APIs to manipulate arrays.

JavaScript offers tons of methods to control, but querying methods were not provided until ES5. The APIs from ES5 decrease the codes and rapidly increase the readability.