Interview Preparation Playground

📖 Documentation: https://gauravagarwalgarg.github.io/playground/

📦 Repository: GitHub

Structured, compilable, interview-ready code across multiple languages. DSA, System Design, LLD, OS, Networking, Databases, Design Patterns, and more.

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Repository Structure

Playground/
├── Languages/                 # All programming languages
│   ├── cpp/                   # C++20, CMake
│   ├── c/                     # C11, Makefile
│   ├── python/                # Python 3, pytest
│   ├── go/                    # Go modules
│   ├── java/                  # Java, javac
│   ├── javascript/            # ES Modules, node:test
│   └── rust/                  # Cargo
│
├── SoftwareEngineering/       # Architecture, Design, Process
├── Linux/                     # Kernel, scripts, cloud ops
├── Notes/                     # Conferences, tech talks, courses
└── Reads/                     # Book notes and reading list

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Languages

Each language follows the same internal structure:

<language>/
├── algorithms-dsa/
│   ├── patterns/              # Two Pointers, Sliding Window, BFS/DFS, DP, etc.
│   └── leetcode/              # By topic: arrays, trees, graphs, dp, heap, etc.
├── system-design-hld/
│   ├── fundamentals/          # Load balancers, caching, CAP, estimation
│   └── problems/              # URL Shortener, YouTube, Twitter, etc.
├── low-level-design-lld/
│   ├── design-patterns/       # GoF: Singleton, Observer, Factory, Strategy...
│   ├── solid/                 # SOLID principles with code
│   └── problems/              # Parking Lot, Elevator, LRU Cache, Order Book
├── computer-core/
│   ├── operating-systems/     # Threads, mutexes, scheduling, signals
│   ├── networking/            # TCP/UDP, sockets, HTTP
│   └── databases/             # SQL, indexing, ACID, sharding
├── application-core/
│   ├── webapp/                # REST APIs, web servers
│   └── embedded-systems/      # GPIO, RTOS, I2C/SPI
└── frameworks-libraries/      # Language-specific frameworks

Language	Build	Run	Frameworks
C++	cmake .. && make	./bin/<name>	-
C	make	./bin/<name>	-
Python	-	python <file>.py	Django, Flask, FastAPI, PyTorch
Go	-	go run <file>.go	Gin, gRPC
Java	javac	java -ea <Class>	Spring, Gradle
JavaScript	-	node --test	React, Angular, Express, Next.js
Rust	cargo build	cargo test	Actix, Tokio

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Linux

Linux/
├── kernel/                    # Subsystems, modules, device drivers
├── userspace/                 # systemd, cgroups, namespaces
├── scripts/
│   ├── cloud-ops/             # Docker cleanup, K8s status, AWS EC2 list
│   ├── networking/            # Port scan, connectivity checks
│   ├── monitoring/            # System health, disk/CPU/memory
│   └── containers/            # Docker compose helpers
└── IRQ.md                     # Interrupt handling notes

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SoftwareEngineering

SoftwareEngineering/
├── architecture/
│   ├── patterns/              # Microservices, Event-Driven, CQRS, Hexagonal
│   └── distributed-systems/   # CAP, Consensus, Replication, Sharding
├── design/
│   ├── product-design/        # User stories, wireframing, MVP
│   └── api-design/            # REST, GraphQL, gRPC, versioning
├── product-engineering/       # Agile, Scrum, CI/CD, DevOps
└── project-management/        # Estimation, planning, retrospectives

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Notes & Reads

• Notes/ -- Conference notes, tech talks, courses, deep dives
• Reads/ -- Curated reading list: DDIA, Clean Code, SICP, OSTEP, and more

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Quick Start

# C++
cd Languages/cpp && mkdir build && cd build && cmake .. && make && ./bin/algorithms-dsa_leetcode_arrays-hashing_two_sum

# Python
python Languages/python/algorithms-dsa/leetcode/arrays-hashing/two_sum.py

# Go
go run Languages/go/algorithms-dsa/leetcode/arrays_hashing/two_sum.go

# C
cd Languages/c && make && ./bin/algorithms-dsa/leetcode/arrays-hashing/two_sum

# JavaScript
node Languages/javascript/algorithms-dsa/leetcode/arrays-hashing/two_sum.mjs

# Rust
cd Languages/rust && cargo test

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Adding a New Problem

1. Pick the language: Languages/<lang>/
2. Pick the category: algorithms-dsa/leetcode/<topic>/
3. Write the solution with main() + assertions
4. Build and run -- no config edits needed (CMake/Make auto-discover)

Same algorithm, same structure, every language.