System X Engineering

@UCL0iC3sMLP-LP1_tjDKoUJA - 140 subscribers

Hi, I'm Denny — a backend engineer with 13+ years of IT experience (9 years Android, 4 years Java backend). On this channel, I teach working software engineers how to: ✅ Master Java, Spring Boot & Microservices ✅ Crack system design & backend interviews ✅ Grow into senior roles in India and Europe No fluff. No theory dumps. Just real production patterns, war stories, and interview-ready breakdowns from someone who's been in the trenches. 🌐 dennymathew.me 🔗 LinkedIn: linkedin.com/in/dennym-space New video every Wednesday & Saturday.

Home Videos Live Playlists

Mastering SOLID Principles for Backend & Spring Boot (LLD Interviews)

Mastering SOLID Principles for Backend & Spring Boot (LLD Interviews) System X Engineering

49 views - 3 months ago

3.12 A simple end to end framework for modeling any feature

3.12 A simple end to end framework for modeling any feature System X Engineering

21 views - 3 months ago

Pagination — Why We Do Not Show Huge Data All at Once | HLD Ep 3.11

Pagination — Why We Do Not Show Huge Data All at Once | HLD Ep 3.11 System X Engineering

52 views - 3 months ago

Sorting and Ordering — Why "Show Latest First" Is Not a Small Detail | HLD Ep 3.10

Sorting and Ordering — Why "Show Latest First" Is Not a Small Detail | HLD Ep 3.10 System X Engineering

17 views - 3 months ago

Indexing — How to Find Data Faster When Records Become Large | HLD Ep 3.9

Indexing — How to Find Data Faster When Records Become Large | HLD Ep 3.9 System X Engineering

45 views - 3 months ago

Mapping Table — How to Represent Many-to-Many Connections Cleanly | HLD Ep 3.8

Mapping Table — How to Represent Many-to-Many Connections Cleanly | HLD Ep 3.8 System X Engineering

21 views - 3 months ago

Foreign Key — How One Record Points to Another Record | HLD Ep 3.7

Foreign Key — How One Record Points to Another Record | HLD Ep 3.7 System X Engineering

27 views - 3 months ago

Primary Key — Why Every Record Needs a Clear Identity | HLD Ep 3.6

Primary Key — Why Every Record Needs a Clear Identity | HLD Ep 3.6 System X Engineering

41 views - 3 months ago

SQL Joins Explained: INNER, LEFT, RIGHT, FULL OUTER & SELF JOIN

SQL Joins Explained: INNER, LEFT, RIGHT, FULL OUTER & SELF JOIN System X Engineering

40 views - 3 months ago

Data Relationships — How Different Pieces of Data Connect to Each Other | HLD Ep 3.5

Data Relationships — How Different Pieces of Data Connect to Each Other | HLD Ep 3.5 System X Engineering

21 views - 3 months ago

Structured vs Unstructured Data — Why All Data Does Not Look the Same | HLD Ep 3.4

Structured vs Unstructured Data — Why All Data Does Not Look the Same | HLD Ep 3.4 System X Engineering

51 views - 3 months ago

Hot Data vs Cold Data — Why All Stored Data Doesn't Need the Same Speed | HLD Ep 3.3

Hot Data vs Cold Data — Why All Stored Data Doesn't Need the Same Speed | HLD Ep 3.3 System X Engineering

56 views - 3 months ago

Why Reads and Writes Create Different Kinds of Pressure | HLD Ep 3.2

Why Reads and Writes Create Different Kinds of Pressure | HLD Ep 3.2 System X Engineering

32 views - 3 months ago

Why "How Much Data?" Matters Before Designing Any Big System | HLD Ep 3.1

Why "How Much Data?" Matters Before Designing Any Big System | HLD Ep 3.1 System X Engineering

59 views - 3 months ago

Explained the Entire Backend in One Video | Load Balancer, API Gateway, JWT, gRPC, MCP

Explained the Entire Backend in One Video | Load Balancer, API Gateway, JWT, gRPC, MCP System X Engineering

741 views - 3 months ago

From App Open to Server Response — The Full Request Journey Explained | HLD Ep 2.7

From App Open to Server Response — The Full Request Journey Explained | HLD Ep 2.7 System X Engineering

39 views - 3 months ago

Why Your Game Doesn't Lag Every Second — DNS Caching Explained Simply | HLD Ep 2.6

Why Your Game Doesn't Lag Every Second — DNS Caching Explained Simply | HLD Ep 2.6 System X Engineering

84 views - 3 months ago

"Why DNS is Distributed Instead of Centralized | System Design Ep 2.5"

"Why DNS is Distributed Instead of Centralized | System Design Ep 2.5" System X Engineering

216 views - 3 months ago

How REST APIs Actually Work (Backend Engineering Guide)

How REST APIs Actually Work (Backend Engineering Guide) System X Engineering

197 views - 3 months ago

Why DNS Uses Multiple Servers (Not One) Bottleneck & Single Point of Failure Explained | HLD Ep 2.4

Why DNS Uses Multiple Servers (Not One) Bottleneck & Single Point of Failure Explained | HLD Ep 2.4 System X Engineering

22 views - 3 months ago

Why We Use Domain Names Instead of IP Addresses — DNS Explained with a Gaming Example | HLD Ep 2.3

Why We Use Domain Names Instead of IP Addresses — DNS Explained with a Gaming Example | HLD Ep 2.3 System X Engineering

24 views - 3 months ago

How Your Phone Connects to the Internet — ISP, Router & Latency Explained Simply | HLD Ep 2.2

How Your Phone Connects to the Internet — ISP, Router & Latency Explained Simply | HLD Ep 2.2 System X Engineering

93 views - 3 months ago

Networking Basics Every Backend Developer Must Know — IP, DNS & How the Internet Works | HLD Ep 2.1

Networking Basics Every Backend Developer Must Know — IP, DNS & How the Internet Works | HLD Ep 2.1 System X Engineering

81 views - 3 months ago

Stop Memorizing System Design Jargon — Do This Instead (HLD Learning Strategy) | Ep 1.3

Stop Memorizing System Design Jargon — Do This Instead (HLD Learning Strategy) | Ep 1.3 System X Engineering

125 views - 3 months ago

What is System Design Actually Solving? The Real Mindset Behind HLD | System Design Ep 1.2

What is System Design Actually Solving? The Real Mindset Behind HLD | System Design Ep 1.2 System X Engineering

87 views - 4 months ago

LRU Cache Explained in 5 Minutes — Why Netflix Deletes Your Watch History (System Design)

LRU Cache Explained in 5 Minutes — Why Netflix Deletes Your Watch History (System Design) System X Engineering

83 views - 4 months ago

What is High Level Design? System Design for Complete Beginners (HLD Explained) 1.1

What is High Level Design? System Design for Complete Beginners (HLD Explained) 1.1 System X Engineering

222 views - 4 months ago

System Design Interview: Design Swiggy Step-by-Step (High Level Design Explained)

System Design Interview: Design Swiggy Step-by-Step (High Level Design Explained) System X Engineering

47 views - 5 months ago

Kubernetes Explained in 7 Minutes — Beginner's Guide to K8s (No Fluff)

Kubernetes Explained in 7 Minutes — Beginner's Guide to K8s (No Fluff) System X Engineering

32 views - 5 months ago

Docker Crash Course: Containers vs VMs Explained (What Every Dev Must Know)

Docker Crash Course: Containers vs VMs Explained (What Every Dev Must Know) System X Engineering

30 views - 5 months ago

Why Systems Crash in Production — Logging & Monitoring Explained Visually

Why Systems Crash in Production — Logging & Monitoring Explained Visually System X Engineering

84 views - 5 months ago

Cracking the Mobile System Design Interview

Cracking the Mobile System Design Interview System X Engineering

871 views - 9 months ago

Mobile System Design Blueprint

Mobile System Design Blueprint System X Engineering

98 views - 9 months ago

News Feed App System Design

News Feed App System Design System X Engineering

183 views - 9 months ago

Designing a Hotel Booking App

Designing a Hotel Booking App System X Engineering

73 views - 9 months ago

Building the Infinite Scroll Engine

Building the Infinite Scroll Engine System X Engineering

48 views - 9 months ago

Building Mobile Apps

Building Mobile Apps System X Engineering

57 views - 9 months ago

Design a Chat App

Design a Chat App System X Engineering

94 views - 9 months ago

Stock App System Design

Stock App System Design System X Engineering

248 views - 9 months ago

Designing Google Drive

Designing Google Drive System X Engineering

60 views - 9 months ago