
<Image alt="React Re-Renders article cover illustration" src="react-rerender.png" priority={true} />

Hi, react [Andy](https://en.wiktionary.org/wiki/react_Andy)!

I’ve used React for over six years. I’ve noticed that even skilled programmers often struggle to grasp how React
operates behind the scenes. This can lead to inefficiencies. It affects code quality, speed, and user experience.

The documentation is great for starting with React. Many [books](https://www.roadtoreact.com/), courses, and blogs focus
on beginners. But what comes next? How can you dive deeper and really understand how it works? If you’ve been writing
React for a while, basic or
even intermediate courses may not be enough. Sadly, resources for advanced learning are limited.

That’s why I’m launching a [series of articles](/blog/category/advanced-react) to fill this knowledge gap.

## Intro to re-renders

Understanding re-renders in React is crucial for performance. You need to understand what triggers them. Know how they
move through the app. Learn what happens during a re-render and why it matters.

<Image alt="Meme about React re-renders" src="react-meme.png" />

## The problem

Imagine you’re an intern at a FAANG company. Your first task is to create a new React component. You’re asked to add a
simple `button` that opens a `modal dialog` at the top of the app.

```jsx
const App = () => {
  // Some code here
  return <div className="layout">
    {/* The button should go somewhere here */}
    <VerySlowComponent />
    <AnotherComponent />
    <OtherStuff />
  </div>;
};
```

Then you implement it. The task seems trivial. We've all done it hundreds of times:

```jsx
const App = () => {
  // Add state  
  const [isOpen, setIsOpen] = useState(false);

  // Everything that is returned here will be re-rendered when the state is updated
  return <div>
    {/* Add the button */}
    <Button onClick={() => setIsOpen(true)}>
      Open dialog
    </Button>

    {/* Add the dialog */}
    {isOpen && <ModalDialog onClose={() => setIsOpen(false)} />}

    <VerySlowComponent />
    <AnotherComponent />
    <OtherStuff />
  </div>;
};
```

You add [state](https://react.dev/learn/state-a-components-memory) to track if the dialog is open or closed. You include
a button to change the state and render the dialog
based on this state.

When you run the app, there’s a noticeable delay ⏰, **almost a second** — before the dialog appears.

Experienced React developers might quickly suggest.

> "You’re re-rendering the whole app. Just wrap everything in [React.memo](https://react.dev/reference/react/memo) and
> use [useCallback](https://react.dev/reference/react/useCallback) to avoid unnecessary renders."

This advice has its place, but it’s wise to pause before jumping in. In this case, memoization isn’t needed and could
hurt performance.

First, let’s take a closer look at what exactly is happening and why this delay occurs.

<Image alt="Diagram showing React component tree re-rendering when state updates" src="rerender.png" />

When we click the button, we trigger the `setIsOpen` setter function, which updates the `isOpen` state from `false` to
`true`. As a result, the `App` component that holds this state re-renders itself.

After the state updates and the `App` component re-renders, React must pass the new data to other dependent components.
It automatically re-renders all components that the first component shows. It keeps going down the tree until it reaches
the end.

If you visualize a typical React app as a tree structure, you will find that everything beneath the point where the
state update was initiated will be re-rendered.

> Re-rendering is crucial to understand in React.

The key point to remember is that React never re-renders components "up" the render tree. If a state update occurs in
the middle of the component tree, only the components "down" the tree will be re-rendered.

<Image alt="Diagram showing re-renders propagating down the component tree from state update" src="rerender-state.png" />

When a component is wrapped in `React.memo`, `React` will interrupt its default re-rendering process and first evaluate
whether the `props` have changed. If there are no changes to the `props`, re-renders will be halted. However, if even a
single `prop` is modified, the re-rendering will proceed as usual.

It's important to note that effectively preventing re-renders through memoization is a nuanced topic with various
considerations. For a deeper understanding, it is advisable to explore these concepts further in new articles. (Coming soon... or read about [Elements, Children as Props, and Re-Renders](/blog/react-elements-children))

<Image alt="Diagram showing how React.memo prevents unnecessary re-renders" src="react-memo.png" />


Wrapping components with `React.memo` can indeed help prevent unnecessary re-renders in certain scenarios. However, it's
important to note that using `React.memo` comes with its own set of complexities and caveats, which will be discussed in
future articles. A more effective approach is to isolate the components that rely on specific state and encapsulate both
the state and those components into a smaller, dedicated component. This can lead to improved performance and a clearer
component structure.

## Moving state down

Let's move our logic in separated component.

```jsx
const ButtonWithModalDialog = () => {
  const [isOpen, setIsOpen] = useState(false);

  return <>
    <Button onClick={() => setIsOpen(true)}>
      Open dialog
    </Button>

    {isOpen && <ModalDialog onClose={() => setIsOpen(false)} />}
  </>;
};
```

And then render this new component in the `App`:

```jsx
const App = () => {
  return <div>
    // Our new component
    <ButtonWithModalDialog />

    <VerySlowComponent />
    <AnotherComponent />
    <OtherStuffComponent />
  </div>;
};
```

<Image alt="Diagram showing performance improvement after moving state to a separate component" src="rerender-performance-fix.png" />

Consequently, the modal dialog appears immediately. We resolved a significant performance issue using a straightforward
composition technique!


Dive into the mechanics of React re-renders — learn what causes them, how they impact performance, and how to manage them effectively.

Understanding React Re-Renders: What Triggers Them and Why They Matter


### Understanding the Hidden Pitfalls of Custom Hooks in React

In a previous post we covered [How React Rerenders Works](/blog/react-rerender). But today, we'll take a closer look at
the hidden pitfalls of custom hooks in React.

<Image alt="Hand-drawn diagram showing 'Custom React Hooks' as the main title with small hook illustrations, 'useEffect ( )' written in blue text on the left, and the React logo (atomic symbol) in blue on the bottom right." src="hooks.jpg" priority={true} />

When we handle state, component re-renders, and application performance in React, custom hooks are a powerful tool that
help us keep our components clean and manageable. However, this simplicity can sometimes hide performance issues that we
may not immediately notice.

Consider a basic custom hook for toggling the visibility of a tooltip:

```jsx
const useTooltipToggle = () => {
  const [visible, setVisible] = useState(false);

  return {
    visible,
    show: () => setVisible(true),
    hide: () => setVisible(false),
  };
};
```

Using this hook in a component might look neat and clean:

```jsx
const App = () => {
  const {
    visible,
    show,
    hide
  } = useTooltipToggle();

  return (
    <div className="app-container">
      <button onMouseEnter={show} onMouseLeave={hide}>Hover me!</button>
      {visible && <Tooltip text="Hello, Tooltip!" />}
      <HeavyComputationComponent />
      <AnotherIntensiveComponent />
    </div>
  );
};
```

At first glance, this setup appears elegant—state logic neatly wrapped in the `useTooltipToggle` hook. However, this
approach hides a subtle performance issue: whenever the tooltip visibility state changes, React re-renders the entire
`App` component, despite the state being limited to a small interaction.

> Why? You can read more about react rerenders [here](/blog/react-rerender).

### Hidden States and Re-rendering Pitfalls

Let's extend our custom hook to listen for a scroll event:

```jsx
const useTooltipToggle = () => {
  const [scrollPosition, setScrollPosition] = useState(window.scrollY);

  useEffect(() => {
    const handleScroll = () => setScrollPosition(window.scrollY);
    window.addEventListener('scroll', handleScroll);

    return () => window.removeEventListener('scroll', handleScroll);
  }, []);

  return {
    // For example, this part of the code was simplified
    visible: false,
    show: () => {},
    hide: () => {},
  };
};
```

Now, every time the user scrolls, this hook updates the state internally. Even though the scrolling position isn't
returned or directly used, it **triggers state changes**, causing the entire `App` to re-render unnecessarily.

### Nested Hooks Can Multiply Issues

The problem worsens when custom hooks depend on other hooks indirectly. For example, consider another hook for tracking
mouse movement:

```jsx
const useMouseTracker = () => {
  const [mousePosition, setMousePosition] = useState({
    x: 0,
    y: 0
  });

  useEffect(() => {
    const updateMousePosition = (e) => setMousePosition({
      x: e.clientX,
      y: e.clientY
    });
    window.addEventListener('mousemove', updateMousePosition);

    return () => window.removeEventListener('mousemove', updateMousePosition);
  }, []);

  return null;
};

const useTooltipToggle = () => {
  useMouseTracker();

  return {
    // For example, this part of the code was simplified
    visible: false,
    show: () => {},
    hide: () => {},
  };
};
```

Even if `useTooltipToggle` does not directly use mouse position state, the `App` component still re-renders each time
the mouse moves, since the state is updated inside the nested hook.

> Hiding stateful logic within hooks doesn't remove their performance impact. The
> solution isn’t hiding complexity but smartly managing and isolating the state.

### How to Solve This

To avoid such issues, encapsulate state logic in smaller components:

```jsx
const Tooltip = () => {
  const {
    visible,
    show,
    hide
  } = useTooltipToggle();

  return (
    <>
      <button onMouseEnter={show} onMouseLeave={hide}>Hover me!</button>
      {visible && <Tooltip text="Hello, Tooltip!" />}
    </>
  );
};
```

This ensures that the minimal required area re-renders, preventing unnecessary updates across the entire app.

> In this solution, the `Tooltip` logic moved down from `App` to the own component. I described this approach in
> [this article](/blog/react-rerender#moving-state-down).

### Key Takeaway

The key lesson: carefully handle state encapsulation within custom hooks. Keep state management local and focused to
optimize your React application's performance and responsiveness.

> P.S Memoization and other performance optimizations will be covered in future posts. Meanwhile, you can read about [Elements, Children as Props, and Re-Renders](/blog/react-elements-children).


Learn about performance risks in React custom hooks, how they cause unexpected re-renders, and strategies to manage state efficiently.

Understanding the Hidden Pitfalls of Custom Hooks in React


Hi, React developers!

In my previous [post](/blog/react-rerender), we explored the mechanics of re-renders and how to fix performance issues
by "moving state down." We solved the "slow modal" problem by isolating the state into a smaller component, leaving the
rest of the heavy app alone.

But what happens when you can't move the state down?

Imagine you are that same developer at a FAANG company. You’ve just optimized the modal, but now your PM asks for a new
feature: a "scroll progress" block that wraps the entire main content area.

## The Problem

The requirements are strict:

* A block that tracks the scroll position.
* It wraps `VerySlowComponent`, `BunchOfStuff`, and `OtherStuffAlsoComplicated`.
* As you scroll, a small UI element inside the wrapper needs to move/animate based on that scroll position.

Your first instinct might be to wrap everything in a div with an onScroll handler (or maybe try to hide the logic in
a [custom hook](/blog/react-hooks-pitfalls), which often doesn't help):

```jsx
const App = () => {
  // We need this state for the moving block
  const [scrollPosition, setScrollPosition] = useState(0);

  const handleScroll = (e) => {
    setScrollPosition(e.target.scrollTop);
  };

  return (
    <div className="scrollable-block" onScroll={handleScroll}>
      <MovingBlock position={scrollPosition} />

      {/* 😱 These will re-render on EVERY scroll event! */}
      <VerySlowComponent />
      <BunchOfStuff />
      <OtherStuffAlsoComplicated />
    </div>
  );
};
```

<Image src="elements.png" alt="" />

If you run this, the app will crawl. Every pixel you scroll triggers a state update in `App`. Since `App` re-renders,
React re-renders everything inside it. The "moving state down" trick won't work easily here because the `div` wraps the
content. The state needs to be high up.

Is `React.memo` the only escape hatch? No. There is a more elegant composition pattern that relies on understanding the
difference between a Component and an Element.

## The Solution: Children as Props

Let’s extract that scroll logic into its own component, but with a twist. Instead of hard-coding the slow components
inside, we accept them as children.

```jsx
const ScrollableWithMovingBlock = ({ children }) => {
  const [position, setPosition] = useState(0);

  const handleScroll = (e) => {
    setPosition(e.target.scrollTop);
  };

  return (
    <div className="scrollable-block" onScroll={handleScroll}>
      <MovingBlock position={position} />
      {children}
    </div>
  );
};
```

Now, we rewrite our `App`:

```jsx
const App = () => {
  return (
    <ScrollableWithMovingBlock>
      {/* These are now passed as props! */}
      <VerySlowComponent />
      <BunchOfStuff />
      <OtherStuffAlsoComplicated />
    </ScrollableWithMovingBlock>
  );
};
```

Result: The scroll animation is buttery smooth. The heavy components do not re-render, even though they appear "inside"
the component that is updating 60 times a second.

## Why does this work? (The Deep Dive)

To understand this, we need to distinguish between a **Component** and an **Element**.

A **Component** is a function (e.g., `App` or `ScrollableWithMovingBlock`).

An **Element** is an object that describes what to render (e.g., `{ type: 'div', props: ... }`).

When `App` renders, it creates the elements for `<VerySlowComponent />` and its friends. It passes these Element objects
to `ScrollableWithMovingBlock` via the `children` prop.

Now, look at the render timeline:

1. **User Scrolls**: `ScrollableWithMovingBlock` updates its position state.
2. **Re-render**: `ScrollableWithMovingBlock` re-executes its function.
3. **The Return**: It returns a new `div` with the new `MovingBlock`. But for `{children}`, it uses the exact same
   reference it received from `App`.
4. **Reconciliation**: React looks at the `children` prop. It asks: "Did this object change?"
5. **The Check**: Since `App` (the owner) didn't re-render, the children object is referentially identical (`===`).
   React sees this and says, "Okay, no need to touch this subtree."

## Syntax Sugar

It's important to remember that `children` is just a prop like any other. The "nesting" syntax is just JSX sugar.
Creating an element is just a [JavaScript expression](/blog/expressions-statements), not a statement. This code:

```jsx
<Parent>
  <Child />
</Parent>
```

Is strictly equivalent to this:

```jsx
<Parent children={<Child />} />
```

You could even name the prop `content` or `body` if you wanted. As long as the Element object is created in the parent
scope (which isn't re-rendering) and passed down, the child will be preserved.

## Summary

In the previous article, we fixed performance by [moving state down](/blog/react-rerender#moving-state-down) into a
child. Today we fixed it by passing the heavy UI down as props.

Both strategies achieve the same goal: separating the part that changes from the part that remains static.



Learn how React elements work and how passing children as props can optimize performance by preventing unnecessary re-renders.

React Elements, Children as Props, and Re-Renders


<Image src="exit.jpg" alt="black and green led light" />

Today, while wrestling with some code, I caught myself smiling at something small but powerful. I was deep in a function
that was starting to look like a staircase of if statements. Halfway through, I stopped and thought: _why am I dragging
all these checks down the page when I could just step out early_?

That’s when it clicked—again 🥳. Early return (or guard clauses, if you like fancy names) isn’t just a coding pattern;
it’s a way of freeing your own brain. You handle the simplest, most obvious stuff first and politely bow out of the
function. Then the rest of the logic can flow without carrying the weight of those initial conditions.

```javascript
function processUser(user) {
  if (!user) return;          // nothing to process
  if (!user.isActive) return; // skip inactive users

  sendWelcomeEmail(user);
  updateAnalytics(user);
}
```

Once those guard clauses are in place, I don’t have to `mentally juggle` those “what ifs” anymore. They’re dealt with.
The rest of the code reads like a straight road.

Before I got into this habit, my functions often looked like a pile of _stacked boxes—each_ if wrapped inside another.
It
worked, but it forced every reader (including future me) to carry all those checks in their head all the way down.

```javascript
function processUser(user) {
  if (user) {
    if (user.isActive) {
      sendWelcomeEmail(user);
      updateAnalytics(user);
    }
  }
}
```

This still runs fine, but it makes you think about conditions long after you should’ve moved on.

The beauty of early return is that it clears `mental space`.

> You make the easy decisions first, exit where needed, and
> leave the interesting logic standing in the light. It’s not just about fewer braces—it’s about respecting your own
> attention span.

It’s funny how these little patterns sneak up on you. Today’s code reminded me that writing for humans, including future
me—is just as important as writing for the machine.


Discover how early return and guard clauses can simplify your JavaScript functions, reduce nesting, and free your mind to focus on the real logic.

Why Early Return Makes Your JavaScript Easier to Read


<Image alt="A hand-drawn diagram showing Generic Type Parameters on the left and a browser window with TypeScript code for a generic identity function on the right, plus two boxes labeled U and V" src="generic.jpg" priority={true} />

When you first encounter TypeScript generics, you'll likely see something
like [this](https://www.typescriptlang.org/docs/handbook/2/generics.html#hello-world-of-generics):

```typescript
function identity<T>(arg: T): T {
  return arg;
}
```

That lonely **T** sitting there might seem mysterious.

Why T? What if you need more than one? And when should you graduate from single letters to something more descriptive?
Let's dive into the world of generic naming conventions and figure out what actually makes sense.

## The Classic Lineup: T, U, V, W

The **T** convention comes from mathematics and early programming languages. It simply stands for "Type" – nothing
fancy.
When you need multiple generic parameters, the tradition is to march through the alphabet:

```typescript
// Two types? Add U
function pair<T, U>(first: T, second: U): [T, U] {
  return [first, second];
}

// Three types? Bring in V
function triple<T, U, V>(first: T, second: U, third: V): [T, U, V] {
  return [first, second, third];
}
```

This alphabetical progression isn't arbitrary – it creates a clear, predictable pattern that developers can follow
easily. Plus, these single letters are visually distinct and don't clutter your code.

> This naming convention is common in different languages,
> like [Java](https://docs.oracle.com/javase/tutorial/java/generics/types.html) and others.

## When Single Letters Work Perfectly

For simple, general-purpose functions and utilities, single letters are your best friend:

```typescript
// Array mapping - crystal clear what T and U represent
function map<T, U>(items: T[], transform: (item: T) => U): U[] {
  return items.map(transform);
}

// Key-value pairs - K and V are intuitive
interface Dictionary<K, V> {
  [key: K]: V;
}
```

> Notice how TypeScript's own built-in utilities follow this pattern. `Pick<T, K>`, `Omit<T, K>`, `Record<K, V>` – they
> stick with meaningful single letters because the context makes their purpose obvious.

## The Case for Descriptive Names

Sometimes, though, single letters leave your future self (and your teammates) scratching their heads. That's when
descriptive names shine:

```typescript
// What are T and U supposed to represent here?
interface ApiClient<T, U> {
  get(endpoint: string): Promise<T>;
  handleError(error: U): void;
}

// Much clearer!
interface ApiClient<ResponseData, ErrorType> {
  get(endpoint: string): Promise<ResponseData>;
  handleError(error: ErrorType): void;
}
```

This is especially valuable in domain - specific code where the generic types have special meaning in your business logic.

## The Repository Pattern Example

Here's where descriptive naming really pays off:

```typescript

interface Repository<Entity, Key> {
  findById(id: Key): Promise<Entity | null>;
  save(entity: Entity): Promise<Key>;
  delete(id: Key): Promise<void>;
  findAll(): Promise<Entity[]>;
}


class UserRepository implements Repository<User, string> {
  // Implementation details...
}
```

Anyone reading this code immediately understands what **Entity** and **Key** represent.
Compare that to `Repository<T, U>` – you'd need to dig into the implementation to figure out which is which.

## The T Prefix Debate

You'll sometimes see generic parameters prefixed with T:

```typescript
interface Repository<TEntity, TKey> {
  findById(id: TKey): Promise<TEntity>;
}
```

This convention comes from [C#](https://learn.microsoft.com/en-us/dotnet/api/system.collections.generic?view=net-9.0) and serves a purpose – it clearly marks something as a **type parameter** rather than a
**regular variable**. But it's not universally loved.

TypeScript's own standard library doesn't use the T prefix.
React components rarely use it. Many JavaScript and TypeScript projects skip it entirely:

```typescript
// Both are perfectly valid
interface Props<User, Settings> {}
interface Props<TUser, TSettings> {}
```

The choice often comes down to team preference and consistency with your existing codebase. Pick one style and stick
with it.

## Practical Guidelines

Here's what I've learned from years of writing TypeScript:

### Use single letters when:

- Writing utility functions that work with any type 
- The generic's role is obvious from context 
- You're following established patterns (like `map<T, U>`)

### Use descriptive names when:

- The generics have a specific domain meaning 
- You have multiple related type parameters 
- Code clarity would suffer with single letters

### Stay consistent:

- Whatever convention your team chooses, apply it everywhere 
- Don't mix T prefixes with non-prefixed names randomly 
- Document your team's preferred style

## Common Single-Letter Conventions

```typescript
T // Primary type parameter
U, V, W // Additional type parameters (alphabetical order)
K // Key type (in mappings, records)
V // Value type (in key-value structures)
E // Element type (in collections)
R // Return type
P // Properties/Props type
```

## Wrapping Up

- **Consistency beats perfection** – pick a style and stick with it 
- **Context is king – choose names** that make sense for your specific use case 
- **When in doubt, be descriptive** – clarity trumps brevity in complex code 
- **Follow your team's conventions** – consistency across the codebase matters most

> I love conventions and wrote a lot of articles about them.
> Check out about [conventional commits](/blog/conventional-commits) and [JavaScript Naming](/blog/javascript-naming-conventions) for more.


Learn TypeScript generic type parameter naming conventions. Understand when to use T, K, V and when descriptive names like TKey make your code more readable.

What is a generic type parameter T in TypeScript?


If you’re interested in GraphQL but haven’t had the chance to explore it directly, it's time to take action.
[Apollo Odyssey](https://www.apollographql.com/tutorials/) is the perfect solution to help you understand how it all
fits together!

<Image alt="Apollo Graph Developer - Associate certificate. Serhii Shramko" src="graphql-certificate.png" priority={true} />

## Apollo Odyssey: Free Learning Platform

The learning platform features a variety of paths, combining video tutorials with written guides that include quizzes
and code challenges for reinforcement.

<Image alt="Apollo Odyssey: Learning Platform video" src="graphql-apollo-odyssey.png" />


To earn
the [Apollo Graph Developer - Associate certification](https://www.apollographql.com/tutorials/certifications/apollo-graph-associate),
you must complete the first four paths:

- [Basics](https://www.apollographql.com/tutorials/lift-off-part1)
- [Resolvers](https://www.apollographql.com/tutorials/lift-off-part2)
- [Arguments](https://www.apollographql.com/tutorials/lift-off-part3)
- [Mutations](https://www.apollographql.com/tutorials/lift-off-part4)

> Developers who obtain this certification possess a solid foundational knowledge of GraphQL and the Apollo tool suite
> to design a schema, run an Apollo Server 4, and perform queries with Apollo Client 3 on the frontend.

I absolutely love this platform! It features fantastic videos, clear explanations, and some really good jokes that
always make me smile. 😀

## Apollo Graph Developer - Associate

As you work your way through the four required tutorials, you will be creating a real-world application called
`Catstronauts`.

<Image alt="Catstronauts project. React & GraphQL application" src="catstronauts.png" />

This project consists of a frontend client built with _TypeScript_ and _React_, alongside a backend server that utilizes
_Node.js_ as its runtime environment and [Apollo Server](https://www.apollographql.com/docs/apollo-server) as a
standalone, spec-compliant GraphQL server.

## Certification exam

- 31 multiple choice questions
- 25 correct answers required to pass

I achieved success in my test, making only a single error.

This outcome highlights the effectiveness of the course, which comprehensively addresses all relevant material,
equipping me with the confidence to approach the exam calmly.

## Graph Developer - Professional

Well, now the next step is to gain a deeper knowledge of GraphQL and
get [Graph Developer - Professional](https://www.apollographql.com/tutorials/certifications/apollo-graph-professional)
certification.

> Developers who obtain this certification demonstrate strong familiarity with Apollo Federation concepts. They can
> apply those concepts to build a federated supergraph or move an existing monolithic graph to federation.

I really commend the [Raphael Terrier](https://www.linkedin.com/in/raphaelterrier/)
and [Michelle Mabuyo](https://www.linkedin.com/in/michellemabuyo/) for developing such an excellent learning course.


My journey to getting Apollo GraphQL certification for free. Learn about the exam structure, preparation tips, and how to earn your credential.

How I Got Apollo GraphQL Certification for Free


<Image src="seo.jpg" alt="Ahrefs SEO audit dashboard showing website health score and issues" priority={true} />

I've been putting off an SEO audit of my blog for months. With **30+** articles and **20+** code snippets, the task felt overwhelming. Reviewing each meta description, checking for broken links, validating alt text — it's the kind of work that's *easy to procrastinate* on indefinitely.

Then I tried something different: I used AI as my editorial assistant. In a single afternoon, I audited and improved **56 files**. Here's how it went.

## The Boring Work Nobody Wants to Do

Let's be honest — SEO maintenance is *boring*. It's not the exciting part of running a developer blog. You know you should do it, but there's always something more interesting to work on.

My blog had accumulated typical SEO debt over time. Generic meta descriptions that said nothing specific, like "Learn about X" instead of actual summaries. Broken external links because MDN reorganized their docs and Git changed their download URL. Empty alt attributes on images where I'd rushed through posts and left `alt=""`. The usual mess.

Fixing this manually would mean opening each file, reading the content, rewriting descriptions, and validating every link. For 56 files? That's a full weekend I'd *never* actually spend.

## Teaching AI What I Need

The key insight was treating AI not as a magic "fix everything" button, but as a *focused assistant* with clear constraints. I use [Cursor](https://www.cursor.com/) as my editor, and it supports [project-specific rules](https://docs.cursor.com/context/rules) — markdown files that act as persistent instructions for the AI.

I created a rules file (`.cursor/rules/seo.mdc`) that defined exactly what I needed:

```markdown
SEO responsibilities:
- Propose 2–5 realistic, developer-focused keyword phrases for each article
- Suggest an SEO-friendly title (50-60 characters) and meta description (110-160 characters)
- Naturally integrate the main keyword into title, first paragraph, and conclusion
- Never sacrifice clarity or honesty for SEO
```

This file acts as persistent context. Every time the AI reviews an article, it knows who I am (a senior software engineer), who my audience is (developers from junior to senior level), my writing style (conversational, direct, technical), and what to avoid (inventing experience, adding buzzwords, breaking code).

That last constraint — *"never sacrifice clarity for SEO"* — is crucial. I've seen AI-generated content stuffed with keywords that reads like garbage. That's not what I wanted.

## What the SEO Audit Found

<Image src="ahrefs-audit.png" alt="Ahrefs Site Audit results showing SEO issues to fix" />

**Before:**
```text
description: Polymorphism and Dispatch Tables in JS
```

**After:**
```text
description: Replace messy switch statements with dispatch tables in JavaScript. 
Learn this clean code pattern for handling multiple conditions with maintainable code.
```

The first one tells you nothing. The second *explains the benefit*, uses action words, and includes relevant keywords naturally.

MDN restructured their documentation URLs at some point too. Links that worked a year ago now 404. The AI flagged these:

```diff
- [CSS Grid](https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_grid_layout)
+ [CSS Grid](https://developer.mozilla.org/en-US/docs/Web/CSS/Guides/Grid_layout)
```

Same for Flexbox and other external resources. Small fixes, but broken links hurt both SEO and user experience.

Then there was alt text. In my React re-renders article, I had multiple images with *empty* alt attributes:

```diff
- <Image alt="" src="rerender.png" />
+ <Image alt="Diagram showing React component tree re-rendering when state updates" src="rerender.png" />
```

The AI suggested appropriate descriptions based on the surrounding content in seconds.

## Wrapping Up

The goal here isn't to automate away quality control. It's to make the tedious parts *fast enough* that you actually do them.

By the end of the afternoon: **56 files** updated, **50+ meta descriptions** rewritten, **6 broken links** fixed, **12 empty alt attributes** filled.


I used Cursor AI to audit SEO across 56 blog posts in one afternoon. Meta descriptions, broken links, and alt text — all fixed systematically.

I Ran an AI SEO Audit on 56 Blog Posts in One Day

<Image src="git.jpg" alt="Hand-drawn illustration of the Git logo inside a tilted square outline with three red dots connected by black lines, representing branches" priority={true} />

When it comes to managing version control in your project with Git, `.gitignore` files typically handle most cases of
excluding specific files or directories from being tracked. However, there are instances when you either can’t or simply
prefer not to modify the `.gitignore` file directly.

Fortunately, Git offers several alternative methods to tackle these scenarios effectively.

### Why You Might Want to Avoid Modifying .gitignore

There are generally two key situations where you might opt to keep your `.gitignore` unchanged:

1. **Personal or local-specific files:** Say you have custom settings or environment files (like `.envrc` or
   personalized
   IDE configurations). You wouldn’t want to clutter the repository with your personal preferences that aren’t relevant
   to others.
2. **Temporarily ignoring changes to tracked files:** Perhaps you’re making adjustments to a file that’s already under
   version control (such as a Docker configuration or database settings), but you want to ensure these changes don’t
   appear in every commit.

Here’s how to handle both situations gracefully.

### Ignoring untracked files

Git provides a straightforward solution that keeps personal preferences out of sight from collaborators: the
`.git/info/exclude` file. This file acts just like `.gitignore` but remains local—meaning your teammates won’t be
affected
by your individual exclusions.

To put this into action, simply open the `.git/info/exclude` file in your repository and list the files or directories
you
wish to ignore:

```gitignore
.idea/
*.log
.env.local
```

Now, your IDE settings, log files, or local environment configurations will no longer clutter your Git status or lead to
accidental commits without interrupting your teammates’ workflow.

### Temporarily Ignoring Changes with git update-index

At some point, you’ll find it necessary to tweak files you’re already tracking, but you have no intention of committing
those changes (for example, adjusting local ports or temporary debugging code). That’s where the
`git update-index --assume-unchanged` command comes in.

Here’s how it works:

To temporarily ignore changes in a tracked file, simply run:

```bash
git update-index --assume-unchanged docker-compose.yml
```

This command tells Git to overlook any further changes made to `docker-compose.yml`, treating it as if it hasn’t been
modified.

However, use this feature with caution! Overuse can lead to confusion, especially if you forget you’ve set it. To resume
tracking the changes, you can run:

```bash
git update-index --no-assume-unchanged docker-compose.yml
```

If you ever need a quick way to check which files are being ignored, you can use:

```bash
git ls-files -v | grep '^h'
```

This command lists the files that Git currently assumes are unchanged, helping you maintain organization.

### Final Thoughts

While `.gitignore` is a powerful tool, it’s not always enough on its own. By incorporating `.git/info/exclude` and the
`git update-index` technique into your toolkit, you can enjoy greater flexibility in managing your repository.

Precise management leads to fewer headaches and cleaner commits, ensuring a smoother and more intuitive approach to
version control.


Learn about Git's hidden alternatives to .gitignore for managing file exclusions locally without affecting your team's workflow.

When .gitignore Isn't the Right Tool


Let's talk about version numbers in your `package.json`. You've probably seen versions like `1.2.3` or `^4.5.0`—but what
do they *actually* mean?

<Image src="semver.jpg" alt="but it works on *my* machine  joke" />

---

## **SemVer: The Three-Number System That Keeps Everyone Sane**

Semantic Versioning (SemVer) is just a fancy way of saying:  
**"Hey, let's use version numbers to tell people what *kind* of changes we made."**

Versions look like `x.y.z`:

- **Major (x)**: Big changes that might break your code. *Example:* Removing a feature your app relies on.
- **Minor (y)**: New stuff that won't wreck existing code. *Example:* Adding a cool new function.
- **Patch (z)**: Quiet fixes for bugs or security holes. *Example:* Fixing a crash when you type `null`.

Think of it like home renovations:

- **Major** = Tearing down a wall (big impact).
- **Minor** = Adding a new room (no harm done).
- **Patch** = Fixing a leaky faucet (everyone's happy).

---

## **Why Should You Care?**

Because npm uses these numbers to decide which updates are safe to install automatically. If everyone follows SemVer,
your app won't suddenly break when you run `npm update`.

---

## **The Secret Symbols in Your package.json**

Those weird characters like `^` and `~` in your dependencies? They're just rules for npm. Here's what they *really*
mean:

- **`^1.2.3`** = "New features and fixes are okay, but don't change anything big!"  
  *(Updates to 1.3.0 or 1.2.4 are fine. Won't jump to 2.0.0.)*

- **`~1.2.3`** = "Only tiny fixes, please."  
  *(Updates to 1.2.4 are okay. Won't go to 1.3.0.)*

- **`>` or `>=`** = "Give me anything newer than this."
- **`<` or `<=`** = "Nothing newer than this, thanks."
- **`1.2.3` - `1.5.0`** = "I'll take any version between these two."
- **`||`** = "Either version A *or* version B works."

**No symbol?** Example: `"lodash": "4.17.21"` means *"Only this exact version. Don't change a thing!"*

### **Watch Out for 0.x.x Versions**

The caret `^` behaves differently for versions below `1.0.0`:

- **`^0.2.3`** → allows only `0.2.x` (treats minor as major)
- **`^0.0.3`** → allows only `0.0.3` (most restrictive)

This is because pre-1.0 packages are considered unstable, so npm plays it safe.

---

## **But Wait... What About the Lock File?**

Great question! If you've ever wondered *"Why do I need `^` or `~` when `package-lock.json` already pins exact
versions?"*—you're not alone.

Here's the deal: **they serve different purposes**.

|                     | Lock File                      | Symbols (`^`, `~`)          |
|---------------------|--------------------------------|-----------------------------|
| **When it matters** | `npm install`                  | `npm update`                |
| **What it does**    | Freezes "what's installed now" | Defines "update boundaries" |
| **Purpose**         | Reproducibility                | Flexibility                 |

### **When Symbols Actually Matter**

**1. First install (no lock file yet)**

When you run `npm add react` on a fresh project, npm checks the registry for the latest version and writes:

- `package.json`: `"react": "^19.2.1"` (with caret by default)
- `package-lock.json`: `react: 19.2.1` (exact version)

**2. Running `npm update`**

This is where symbols shine:

| In package.json      | What happens on `npm update` |
|----------------------|------------------------------|
| `"react": "19.2.1"`  | ❌ Nothing changes            |
| `"react": "~19.2.1"` | Updates to latest `19.2.x`   |
| `"react": "^19.2.1"` | Updates to latest `19.x.x`   |

**3. Publishing a library**

If you're building an npm package, your lock file is **ignored** by consumers. They only see your `package.json` ranges.
This is why choosing the right symbols matters for library authors.

### **Think of It This Way**

- **Symbols** = the rules for *future* updates
- **Lock file** = a snapshot of *current* state

They work together: symbols say "what's allowed," the lock file says "what's installed." 🤝

---

## **Real-World Tips for Humans**

1. **Start with `^`** for most dependencies. It's the safest way to get bug fixes and new features without surprises.
2. **Use exact versions** for critical packages (like React or Vue) where unexpected changes could ruin your day.
3. **Check `npm outdated` weekly** to see which packages have updates. It's like a to-do list for your app's health.
4. **Commit `package-lock.json`** to avoid "but it works on *my* machine" moments. This file locks down every tiny
   detail.

<Image src="ops.jpg" alt="but it works on *my* machine  joke" />

## **When Things Go Sideways**

- **Broke after an update?** Check if a major version sneaked in. Temporarily pin the version <br/>`"package": "1.2.3"`
  until you fix things.
- **Confused by symbols?** Use [semver.org](https://semver.org/) to understand semantic versioning rules.

---

## **Quick Cheat Sheet**

| Symbol   | What It Means                             |  
|----------|-------------------------------------------|  
| `^1.2.3` | "Keep me up to date, but no big changes!" |  
| `~1.2.3` | "Only bug fixes, please."                 |  
| `1.2.x`  | "Any patch version for 1.2."              |  
| `1.2.3`  | "Only this exact version."                |

---

## **Wrapping Up**

SemVer isn't about memorizing rules—it's about communicating changes clearly. Use `^` for flexibility, `~` for caution,
and exact versions when stability matters. <br/>And always, *always* check your `package-lock.json` into Git.

**Try this now:**

```bash  
npm outdated  
```  

See what updates are waiting? Update one with `npm update package-name` and see if your app still works. You've got
this! 🛠️

---  

*P.S. Sharing is caring. Forward this to a teammate who still edits `package.json` versions by hand. 😉*

## Related Articles

- [Migrate to pnpm](/blog/pnpm) - faster package management with better disk efficiency
- [Conventional Commits](/blog/conventional-commits) - structured commit messages for automated versioning


A friendly, practical guide to SemVer in npm. Learn versioning rules, avoid dependency chaos, and manage updates with confidence.

Serhii Shramko

Senior Software Engineer at BetterMe

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