Stop Scripting.
Start Architecting.

The premier Low-Level Design (LLD) course geared towards Python developers, with full support for Java. Master Object-Oriented Design, Design Patterns, and write scalable production code.

parking_lot.py
Output
> ParkingLot Instance Created: 0x7f...
> Capacity set to 500
Our Methodology

We Don't Just Dump Code.
We Build Mental Models.

Understanding LLD requires visualizing relationships. We use diagram-first teaching to connect abstract classes to real-world instances.

Class (Blueprint)

+ __init__(self)

+ get_info()

Instance 1
obj
data
Instance 2
obj
data

Visual Recaps & Cheat Sheets

Every module ends with a "Remember" card—a high-density summary of the core concepts, perfect for quick revision before interviews.

Remember

  • Class = Blueprint/template for creating objects
  • Object/Instance = Specific example created from a class
  • __init__ = Constructor method called when creating an instance
  • self = Reference to the current instance
  • Each instance is independent - modifying one doesn't affect others

Built for Modern Backend Engineers

We prioritize the Python ecosystem while offering comprehensive Java support. Cover advanced features like decorators, metaclasses, and concurrency in the language you prefer.

Pure OOP Mastery

Stop writing functional spaghetti. Master encapsulation, polymorphism, and abstraction in complex systems.

System Design Patterns

Don't just memorize definitions. Learn when to apply the Strategy pattern vs the State pattern in a distributed microservice environment.

Interview Cracker

Curated specifically for LLD rounds at FAANG, Uber, and top-tier product companies. We cover the exact questions asked in 2024.

Parking Lot
Elevator

Code Reviews

Get your design assignments reviewed by senior engineers. Learn from detailed feedback.

The Roadmap

What You'll Master

We start from the ground up. Revisit the core pillars of OOP to ensure your foundation is rock solid before tackling complex architectures.

Encapsulation & Access Modifiers
Inheritance & Polymorphism
Composition vs Inheritance
UML Class Diagrams

Move beyond basic scripts. Master Python's advanced features to write code that is efficient, readable, and idiomatic.

Type Hints & Annotations
Advanced Dunder Methods
Decorators & Context Managers
Async & Concurrency

The difference between code that works and code that lasts. Learn to apply the 5 principles that define maintainable software.

Single Responsibility (SRP)
Open/Closed (OCP)
Liskov Substitution (LSP)
Dependency Inversion (DIP)

Don't reinvent the wheel. Learn standard, battle-tested solutions to recurring design problems, implemented in pure Python.

Creational (Factory, Singleton)
Structural (Adapter, Facade)
Behavioral (Observer, Strategy)
Thread-safe Implementation

Put it all together. We design real-world systems from scratch, handling database schema, class structure, and edge cases.

Design a Parking Lot
Design Splitwise
Design Movie Ticket Booking
Concurrency Handling

Targeted preparation for the toughest part of the interview loop. We cover frequent LLD questions, schema design, and concurrency challenges asked at top tech companies.

10+ LLD Design Problems
Schema Design (SQL vs NoSQL)
Concurrency & Threading Questions
Soft Skills for Design Reviews
LLD Mastery
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