iiinova — where your digital self keeps evolving

Neo Kim @systemdesign.one · 08/05/2025

Here are some probabilistic data structures you must know as a software engineer (not kidding): They trade accuracy for space efficiency. They're often used in: • Databases • Cache • Search engines • Network infrastructure • Analytics What else should make this list?

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Neo Kim @systemdesign.one · 05/05/2025

If you want to reduce latency, learn these 12 rules:

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Neo Kim @systemdesign.one · 02/05/2025

Give me 2 mins and I'll teach you how DNS works:

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Neo Kim @systemdesign.one · 14/04/2025

Meta achieves 99.99999999% cache consistency. Here’s how they do it (in 2 minutes): —— 👋 PS - I put together a detailed case study with visuals in my newsletter: → newsletter.systemdesign.one/p/cache-cons...

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Neo Kim @systemdesign.one · 11/04/2025

Give me 2 mins and I'll teach you how Disney+ Hotstar scaled to 25M concurrent users—no fluff:

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Neo Kim @systemdesign.one · 10/04/2025

How I’d scale a site to 1 million users—step by step:

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Neo Kim @systemdesign.one · 07/04/2025

HTTP status codes you must know as a web developer in 2025: Status codes are 3-digit numbers returned by a server in response to HTTP requests. It tells the client about the request status and indicates problems if any. So understanding status codes will help you find site errors quickly.

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Neo Kim @systemdesign.one · 06/04/2025

This lady: • Has no tech background • Couldn't draw well as a kid • Knew nothing about venture capitalists Yet she's worth $5.8 Billion - at 37.

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Neo Kim @systemdesign.one · 02/04/2025

How to write clean code. The KYD-DTC Playbook:

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Neo Kim @systemdesign.one · 01/04/2025

Give me 2 mins and I'll teach you how a database stores passwords securely (not kidding):

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Neo Kim @systemdesign.one · 29/03/2025

Give me 2 mins and I'll teach you how Amazon S3 (actually) works:

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Neo Kim @systemdesign.one · 27/03/2025

I spent hours studying how Apple Pay works, so you don't have to. Here's what I learned distilled into 9 sentences:

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Neo Kim @systemdesign.one · 24/03/2025

Popular apps and open-source alternatives: What else should make this list? • Microsoft Office → Libre Office • WhatsApp → Signal • Google Chrome → Mozilla Firefox • Adobe Photoshop → Krita • Google → DuckDuckGo • Windows / Mac → GNU Linux

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Neo Kim @systemdesign.one · 23/03/2025

Give me 2 minutes and I'll teach you how YouTube supports 2.49 billion users with MySQL (not kidding):

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Neo Kim @systemdesign.one · 22/03/2025

I spent hours studying how Amazon S3 achieves 99.999999999% durability — because S3 is the new norm. Here's what I learned distilled into 12 sentences (not kidding):

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Neo Kim @systemdesign.one · 21/03/2025

Git has 152 commands. But most people don't know the powerful ones. Here are the 4 must learn Git commands (bookmark this):

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Neo Kim @systemdesign.one · 20/03/2025

Give me 2 minutes, and I'll teach you how Uber computes ETA (not kidding):

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Neo Kim @systemdesign.one · 19/03/2025

I spent hours studying how Amazon Lambda works — because Serverless is the new norm. Here's what I learned distilled into 11 sentences (you'll thank me later):

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Neo Kim @systemdesign.one · 18/03/2025

If you want to become good at system design (I'm not joking), learn these case studies:

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Neo Kim @systemdesign.one · 17/03/2025

14 Redis use cases you must know as a software engineer (bookmark this): What else should make the list?

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Neo Kim @systemdesign.one · 16/03/2025

Bad vs Good Software Engineers What else should make this list?

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Neo Kim @systemdesign.one · 15/03/2025

How the browser changes video quality automatically while streaming. I spent hours studying about it, so you don't have to. Here's what I learned (without the fluff):

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Neo Kim @systemdesign.one · 11/03/2025

Bad Debugging vs Good Debugging What else should make this list?

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Neo Kim @systemdesign.one · 07/03/2025

Give me 2 minutes, and I'll teach you how CloudFlare serves 20% of internet traffic with only 15 Postgres clusters:

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Neo Kim @systemdesign.one · 05/03/2025

what is the best JavaScript framework for beginners?

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Neo Kim @systemdesign.one · 05/03/2025

System Design 101 9 Rules for High Throughput // 🧵

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Neo Kim @systemdesign.one · 03/03/2025

System Design 101 12 Rules for Low Latency // 🧵

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Neo Kim @systemdesign.one · 28/02/2025

4 real-time communication patterns you should know as a software engineer (not kidding):

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Neo Kim @systemdesign.one · 21/02/2025

Leetcode Interview's RED FLAG list. If you’re making these 5 mistakes… WE NEED TO TALK 😂

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Neo Kim @systemdesign.one · 19/02/2025

I created a YouTube channel to help you learn system design 2 weeks ago. (And 6,127 people have already joined the channel.) It’ll teach you:

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Neo Kim @systemdesign.one · 16/02/2025

If you could only recommend 1 technical book to read, what would it be? My favorite, highly recommend

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Neo Kim @systemdesign.one · 15/02/2025

The night when I wrote my first newsletter online.

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Neo Kim @systemdesign.one · 12/02/2025

what is the best DATABASE of all time?

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Neo Kim @systemdesign.one · 11/02/2025

This account exists to teach you system design. I spent countless hours studying various engineering case studies. If you want to learn system design fundamentals and understand real-world software architectures, Follow me, @systemdesign.one

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Neo Kim @systemdesign.one · 10/02/2025

System Design Interview RED FLAG list. If you’re making these 5 mistakes… WE NEED TO TALK:

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Neo Kim @systemdesign.one · 09/02/2025

>Tight coupling >Longer test cycles >Slow deployments >Technology lock-in >Longer onboard time >Higher risk of failures >Single point of failures >High codebase complexity >Horizontal scalability issues What did GitHub and Stack Overflow see in Monolith?

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Neo Kim @systemdesign.one · 08/02/2025

what SOFTWARE ARCHITECTURE do you use at work? - monolith - modular monolith - microservices - other (PS - check my bio link to learn system design.)

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Neo Kim @systemdesign.one · 07/02/2025

How to crack the LEETCODE interview (without getting lucky). One of the best things you can do to become good at Leetcode is to study patterns and do mock interviews. And I created a powerful template to help you systematically approach Leetcode interviews. To get it for FREE, just:

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Neo Kim @systemdesign.one · 05/02/2025

14 Redis use cases you should know as a software engineer (you'll thank me later):

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Neo Kim @systemdesign.one · 04/02/2025

If you want to become good at system design (I'm not kidding), learn these case studies:

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Neo Kim @systemdesign.one · 03/02/2025

Give me 2 minutes, and I'll teach you how the ride-hailing app Lyft works (I'm not kidding):

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Neo Kim @systemdesign.one · 02/02/2025

Git has 152 commands. But most people don't know the powerful commands. Here are the 4 must-know Git commands (that one day might save you):

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Reposted by Neo Kim

Neo Kim @systemdesign.one · 01/02/2025

I just created a YouTube channel to help you learn system design (you'll thank me later): It gives you:

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Neo Kim @systemdesign.one · 01/02/2025

I just created a YouTube channel to help you learn system design (you'll thank me later): It gives you:

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Neo Kim @systemdesign.one · 30/01/2025

A gentle reminder for software engineers (you'll thank me later): • Learn SQL before ORM. • Learn Git before Jenkins. • Learn SQL before NoSQL. • Learn CSS before Tailwind. • Learn Linux before Docker. • Learn Solidity before dApps. • Learn English before Python.

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Neo Kim @systemdesign.one · 29/01/2025

System Design 101 How to scale a website to 1 million users: // 🧵

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Neo Kim @systemdesign.one · 28/01/2025

If you want to get started with system design, learn these concepts:

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