Why I Started Writing Everything Down

A personal space to think, learn, and slowly figure things out through writing.

Published: Oct 30, 2025
Read Time: 8 min read
Words: 1,736

#mdx

Why I Write Things Down#

I’ve noticed something simple: if I don’t write things down, I forget them.

This space exists so I can capture ideas, organize what I learn, and more importantly — figure out what I actually understand (and what I don’t).

I don't write because I understand — I write to understand.

How I Try to Learn#

Learn on purpose — not just consume randomly
Use writing to think, not just to record
Keep things organized so future me doesn’t suffer

For me, “intentional learning” just means this:
I come back to things on purpose — not because I forgot, but because I want them to stick. ¹

What I Actually Write About#

Mostly things I don’t want to forget:

Concepts that made something finally “click”
Practical notes from building or debugging things
Tools, patterns, and mental models I keep coming back to

Topics (for now)#

Programming
Systems thinking
Productivity & habits
Personal growth (still figuring this one out)

A Playground for How Things Render#

This section is mostly me testing how things look.

If something feels oddly specific… it probably is.

Desk with notes and coffee — Local assets respect theme preferences.
Source: Custom desk illustration

Sidenotes#

Sidenotes are things I want to say… but not important enough to interrupt the main flow. ¹

Text Styles#

Bold for emphasis
Italics for subtle attention
~~Things I no longer believe~~
inline code

Writing makes knowledge stick a little longer.

Tabs#

console.log("Hello, World!");
 
function sum(a, b) {
  return a + b;
}
 
console.log("Sum =", sum(5, 7));

#include <iostream>
 
int main() {
    std::cout << "Hello, World!" << std::endl;
    int a = 5;
    int b = 7;
    std::cout << "Sum = " << a + b << std::endl;
    return 0;
}

print("Hello, World!")
 
a = 5
b = 7
print("Sum =", a + b)

Steps / Stepper#

01
Step 1: Start somewhere
Don’t overthink it. Just scaffold a project and get something running.
02
Step 2: Add structure
Set up your styling, configs, and anything you’ll need later. It doesn’t have to be perfect — just usable.
03
Step 3: Ship it
Push the code, deploy it, and see what breaks. Fix things as you go — that’s the real process anyway.

File Structure#

WORKSPACE

Button.tsx

Header.tsx

package.json

README.md

Tasks (Things I Say I’ll Do)#

Set this up
Actually write consistently
Go back and refine old notes

Links#

Visit My GitHub

Table Example#

(This is mostly here to test layout and styling — if you’re reading this, you’re probably curious like me 😄)

Topic	Learning Objectives			Current Status
	Plan	Timeline		Level	Progress
	Plan	Start	End	Level	Progress (%)	Completed Items
Technical Skills
Programming (Algorithms)	Reach Intermediate level	01/10	15/12	Intermediate	85%	Completed Algorithms section
System Design	Understand basic architecture	20/11	—	Beginner	30%	Learning High-level Design
Mindset & Modeling
Systems Thinking	Master foundational models	05/10	—	Beginner $\rightarrow$ Intermediate	60%	Wrote about Complexity
Systems Thinking	Apply models to practice	15/11	31/12	Intermediate	20%	Wrote about Complexity
Productivity	Apply Atomic Habits		No fixed deadline	Advanced	95%	Established stable habits
Personal Growth
Personal Growth	Write 5 analytical articles	01/11	15/12	New $\rightarrow$ Beginner	40%	Wrote 2 articles
Personal Growth	Review after 1 month	$x^2 + y^2 = x^2$		Developing	—	N/A
Average Progress			Around 60–70%
Remarks			On the right track and maintaining stability

Math#

Some inline formulas like $F = ma$ , $\vec{p} = \gamma m \vec{v}$ , $E^2 = (pc)^2 + (m_0 c^2)^2$ .

The Standard Model Lagrangian

\begin{aligned} \mathcal{L}_{SM} = &-\frac{1}{4} \color{#00b840}{F_{\mu\nu} F^{\mu\nu}} \\ & + i \bar{\psi} \not D \psi + h.c. \\ & + \psi_i y_{ij} \psi_j \phi + h.c. \\ & + |D_\mu \phi|^2 - V(\phi) \\ & - \frac{1}{4} \color{#00b840}{B_{\mu\nu} B^{\mu\nu}} - \frac{1}{8} tr(\mathbf{W}_{\mu\nu}\mathbf{W}^{\mu\nu}) - \frac{1}{2} tr(\mathbf{G}_{\mu\nu}\mathbf{G}^{\mu\nu}) \end{aligned}

Nested Calculus & Matrices: This combination is used to check if radicals, nested fractions, and matrices break the layout.

\color{#00b840}{J_{\alpha}(x)} = \sum_{n=0}^{\infty} \frac{(-1)^n}{n! \Gamma(n + \alpha + 1)} \left( \frac{x}{2} \right)^{2n+\alpha} \quad \text{and} \quad \mathbf{H} = \begin{pmatrix} \frac{\partial^2 f}{\partial x^2} & \frac{\partial^2 f}{\partial x \partial y} \\ \frac{\partial^2 f}{\partial y \partial x} & \sqrt[3]{ \frac{\int_{-\infty}^{\infty} e^{-t^2} dt}{\zeta(s)} } \end{pmatrix}

Einstein Field Equations: Used to test the rendering of superscripts/subscripts (indices).

\color{#00b840}{R_{\mu \nu}} - \frac{1}{2}R g_{\mu \nu} + \Lambda g_{\mu \nu} = \frac{8 \pi G}{c^4} T_{\mu \nu} \implies \int \left( \frac{c^4}{16 \pi G} (R - 2\Lambda) + \mathcal{L}_M \right) \sqrt{-g} \, d^4x

Code Blocks#

Testing different languages, formats, and edge cases.

Test highlights key-value strings, nested arrays, and null/boolean values.

{
  "app_name": "MDX_Renderer",
  "version": 1.0,
  "features": ["syntax-highlighter", "math-jax"],
  "config": {
    "dark_mode": true,
    "deprecated_field": null,
    "max_retries": 5
  }
}

Test indentation and list visibility without brackets.

server:
  host: "0.0.0.0"
  port: 8080
routes:
  - path: /api/v1
    handler: main_handler
  - path: /health
    check: true

Test the color of keywords (SELECT, WHERE) against table names and strings.

SELECT u.id, u.username, o.total
FROM users u
JOIN orders o ON u.id = o.user_id
WHERE o.status = 'completed'
  AND o.created_at > '2023-01-01'
ORDER BY o.total DESC;

Test special characters like ::, &, 'a (lifetime) and macro println!.

struct User<'a> {
    username: &'a str,
    active: bool,
}
 
fn main() {
    let user = User { username: "Dev", active: true };
    println!("User: {}", user.username);
}

Test background/text color of added line (+) and deleted line (-).

function calculateTotal(price, tax) {
-   return price + price * tax;
+   return price * (1 + tax);
  }

Test hex color code #0f172a

.button-primary {
  background-color: #0f172a;
  color: rgba(255, 255, 255, 0.9);
}
.button-primary:hover {
  transform: translateY(-2px);
}

Custom Components#

Modern MDX lets you embed interactive stuff directly into posts — which is honestly pretty fun to play with.

Chart Demo#

Learning Experiments#

Most things only make sense after you actually try them.

This is a small log from one of those experiments — nothing fancy, just progress over time.

Small, consistent improvements add up more than we expect.

Epoch 1/5
166/166 ━━━━━━━━━━━━━━━━━━━━ 84s 415ms/step - loss: 0.1110 - val_loss: 0.0959
Epoch 2/5
166/166 ━━━━━━━━━━━━━━━━━━━━ 79s 472ms/step - loss: 0.0874 - val_loss: 0.0802
Epoch 3/5
166/166 ━━━━━━━━━━━━━━━━━━━━ 78s 463ms/step - loss: 0.0789 - val_loss: 0.0765
Epoch 4/5
166/166 ━━━━━━━━━━━━━━━━━━━━ 78s 467ms/step - loss: 0.0769 - val_loss: 0.0731
Epoch 5/5
166/166 ━━━━━━━━━━━━━━━━━━━━ 77s 464ms/step - loss: 0.0753 - val_loss: 0.0712

Callouts#

Performance Notes Rendering too many components on the client can reduce FCP (First Contentful Paint).

Consider using Server Components when possible.

Deprecated The getStaticProps function will be deprecated in v15. Switch to the fetch API.

Important Never commit .env files to GitHub.

Seriously.

Closing#

This space will probably change a lot.

Hopefully, I’ll change with it.

views

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Nguyen Xuan Hoa

nguyenxuanhoakhtn@gmail.com