# Nirusaki

> The personal site and journal of Mradul Kumar, known as Nirusaki. Computer science, systems programming, AI/ML, cybersecurity, and useful projects.

## About

I’m Mradul Kumar, also known as Nirusaki.

I like studying computer science, whatever the topic. Systems programming, cybersecurity, and AI/ML are what I’m most drawn to, but I’m happy to follow a question into something unfamiliar. I like understanding how things work, then using that understanding to build something useful.

My projects range from a CHIP-8 emulator and Linux hardware tools to a Rust port of Diner Dash, a machine learning library, and media automation. They give me different problems to work through: interpreting instructions, communicating with hardware, training a model, or keeping a queue running.

I prefer learning the concepts behind a tool over memorizing another framework. With systems, that means looking at memory, processes, and how software talks to the operating system. With AI/ML, it means working through the mathematics and implementing the ideas. With security, it means figuring out why something behaves the way it does.

I also build websites for clients and write notes about what I learn. Some of those notes become walkthroughs; others are a record of a problem I wanted to understand. My GitHub is where I keep the projects and experiments along the way.

## Languages and tools

Languages: Python, JavaScript, C, C++; Tools: CMake, Make, Docker; Databases: PostgreSQL, MongoDB, Redis.

Mradul Kumar uses the name Nirusaki. This site documents personal projects, experiments, notes, and freelance website work.

## Site pages

- [Portfolio](https://nirusaki.tech/): About Nirusaki, skills, projects, freelance experience, awards, and contact information.
- [Journal](https://nirusaki.tech/blogs): Articles and technical notes.
- [RSS feed](https://nirusaki.tech/feed.xml): Recent journal entries.
- [Human credits](https://nirusaki.tech/humans.txt): Site authorship and technologies.

## Profiles and contact

- [GitHub](https://github.com/nirusaki-malaal): Public source code.
- [LinkedIn](https://linkedin.com/in/nirusaki): Professional profile.
- [Telegram](https://t.me/nirusaki): Public profile.
- [Email](mailto:nirusakimalaal@gmail.com): Contact Nirusaki.

## Projects and experiments

- [CHIP-8 Emulator](https://github.com/Nirusaki-Malaal/CHIP-8-EMU): A Cross-Platform CHIP-8 Emulator
- [Neutronix](https://github.com/Nirusaki-Malaal/neutronix): A Simple Machine Learning Library Created From Scratch Using NumPy
- [Port Scanner](https://github.com/Nirusaki-Malaal/PortScanner): Fast, multithreaded non-blocking POSIX TCP port scanner in C.
- [Huion HS64 Wayland Driver](https://github.com/Nirusaki-Malaal/HuionHS64-Wayland): Reverse Engineering Huion HS64 Drawing Tablet X11 Drivers And Settings Manager To GTK4 and Wayland
- [Diner Dash Rust](https://github.com/Nirusaki-Malaal/DinerDashRust): Native reimplementation of Diner Dash (2004) in Rust with Wayland, Windows, Android, and WASM support..
- [Shingaku](https://github.com/Nirusaki-Malaal/shingaku): Academic learning platform and computer-based testing engine with automated PDF parsing and evaluation.
- [Acer PredatorSense](https://github.com/Nirusaki-Malaal/PredatorSense): Native Rust kernel driver, daemon, and GTK4 studio specialized for Acer Predator Helios Neo 16 (PHN16-71)
- [AetherScan](https://github.com/Nirusaki-Malaal/AetherScan): Firefox WebExtension and native messaging daemon for executing and parsing Nmap network diagnostics.
- [Learning-DL](https://github.com/Nirusaki-Malaal/Learning-DL): Neural network architectures and computer vision classifiers implemented from scratch in NumPy and PyTorch.
- [gdrive-uploader-bot](https://github.com/Nirusaki-Malaal/gdrive-uploader-bot): Asynchronous Telegram bot streaming chat media directly to Google Drive.
- [auto-airing-animes](https://github.com/Nirusaki-Malaal/auto-airing-animes): Scheduled anime broadcast tracker, downloader, and Telegram broadcast daemon.
- [video-encoder](https://github.com/Nirusaki-Malaal/video-encoder): Persistent queue-based video encoding daemon using FFMPEG and MongoDB.
- [nith-results-website](https://github.com/Nirusaki-Malaal/nith-results-website): Modern academic performance and result analytics portal for NIT Hamirpur.
- [Auto-Rename](https://github.com/Nirusaki-Malaal/Auto-Rename): Metadata-driven media filename standardizer and Telegram channel bot.
- [FederalRAG](https://github.com/Nirusaki-Malaal/FederalRAG): Local semantic search and RAG explorer for federal court archives and OCR records.
- [phantom-tkl-driver](https://github.com/Nirusaki-Malaal/phantom-tkl-driver): Reverse engineering the Phantom TKL RGB keyboard controls into a native Rust and GTK4 studio for Linux and experimental macOS, with lighting, remapping and macros
- [KeyLogger-X11](https://github.com/Nirusaki-Malaal/KeyLogger-X11): X11 key capture probe, FastAPI telemetry receiver, and monitoring dashboard demonstrating X11 input isolation vulnerabilities.
- [AlexNetWebApp](https://github.com/Nirusaki-Malaal/AlexNetWebApp): An AlexNet Web App

## Freelance experience

- [ADM News Bharat](https://admnewsbharat.com): Developed a news website with frontend, backend, PostgreSQL, and Docker deployment infrastructure.
- [Ghoomne Chalo Adventures](https://ghoomnechaloadventures.com): Designed and developed a website for an adventure travel business.
- [Hola Thrift](https://holathrift.in): Developed an e-commerce website for a thrift clothing business.

## Journal articles

Each Markdown article includes a link to its canonical HTML page.

- [Smol CTF Walkthrough](https://nirusaki.tech/blogs/smol-ctf-walkthrough.md): A complete step-by-step walkthrough for the Smol CTF room: exploiting jsmol2wp LFI to leak wp-config, abusing a backdoored Hello Dolly plugin for RCE, cracking WordPress phpass hashes, pivoting through user accounts via SSH keys and passwordless sudo, and cracking encrypted zip archives for root.
- [How Does a Computer Boot?](https://nirusaki.tech/blogs/how-does-a-computer-boot.md): An exhaustive technical breakdown of the computer boot sequence, featuring multi-stage architectural flowcharts, POST verification assembly, BIOS interrupts, MBR vs GPT partitioning, 16-bit Real Mode, UEFI architecture, and Secure Boot key hierarchies.
- [SQL Injection Intro Part 1](https://nirusaki.tech/blogs/sql-injection-intro-part-1.md): A complete guide to SQL Injection theory followed by individual PortSwigger Security Academy lab walkthroughs, detailing database fingerprinting, schema enumeration, UNION attacks, and string concatenation.
- [PyRAT Write Up](https://nirusaki.tech/blogs/pyrat-writeup.md): A complete walkthrough for the PyRAT CTF room on TryHackMe: discovering a custom TCP Python socket interpreter, popping an initial reverse shell, enumerating git repository configuration for credentials, and abusing an admin prompt to crack root.
- [Break-Me CTF Walkthrough](https://nirusaki.tech/blogs/break-me-ctf-walkthrough.md): A technical walkthrough of the Break-Me CTF machine covering WordPress parameter pollution, Bash IFS command injection, SUID TOCTOU race conditions, and Python NFKC Unicode normalization jail escapes.
- [Mr Robot CTF Walkthrough](https://nirusaki.tech/blogs/mr-robot-ctf-walkthrough.md): A complete step-by-step writeup for the Mr Robot CTF: port scanning, decoding hidden base64 credentials, uploading a simplified PHP reverse shell, cracking MD5 user hashes, and abusing SUID Nmap interactive mode for root access.
- [Beach Box Write-up (TryHackMe)](https://nirusaki.tech/blogs/beach-box-writeup-tryhackme.md): A step-by-step TryHackMe write-up for Beach Box: discovering credentials in HTML comments, exploiting PyYAML unsafe deserialization for RCE, and root privilege escalation via process argument credential reuse.
- [Echo Escape - 2 Write-up (PicoCTF)](https://nirusaki.tech/blogs/echo-escape-2-writeup-picoctf.md): A 32-bit x86 buffer overflow CTF write-up: analyzing 32-bit stack frames in GDB, calculating 44-byte offset to saved EIP, and packing target win() with struct.pack('<I').
- [Echo Escape - 1 Write-up (PicoCTF)](https://nirusaki.tech/blogs/echo-escape-1-writeup-picoctf.md): A step-by-step PicoCTF buffer overflow write-up: analyzing 64-bit stack frames in GDB, calculating buffer offsets, and overwriting saved RIP to execute win().
- [NO FA Write-up (PicoCTF)](https://nirusaki.tech/blogs/no-fa-writeup-picoctf.md): A step-by-step CTF write-up: SQLite database enumeration, password hash cracking, OTP bruteforce, and Flask session cookie exploitation to bypass two-factor auth.
- [TCP-IP and OSI Model](https://nirusaki.tech/blogs/tcp-ip-and-osi-model.md): A raw, unfiltered breakdown of network protocols, layers, and the encapsulation process.
- [Lab - 3: Linux Networking Labs - Encapsulation and Sniffing](https://nirusaki.tech/blogs/linux-networking-labs-day-3-packet-analysis.md): How to tap virtual network links using tcpdump to analyze ARP resolving and ICMP packet encapsulation layers.
- [Lab - 2: Linux Networking Labs - Creating a Virtual Router](https://nirusaki.tech/blogs/linux-networking-labs-day-2-router.md): How to configure a virtual router using Linux network namespaces and enable IP forwarding between different subnets.
- [Lab - 1: Linux Networking Labs - Virtual Switches, Cables, and Namespaces](https://nirusaki.tech/blogs/linux-networking-labs.md): A hands-on guide to Linux network namespaces, veth peers, and bridge devices for constructing virtual LAN environments.
- [User Management in Linux](https://nirusaki.tech/blogs/user-management-in-linux.md): An edgy, comprehensive guide to Linux user accounts, permissions, groups, and understanding useradd, passwd, su, and chmod.
- [How Python Stores Variables and Objects](https://nirusaki.tech/blogs/how-python-stores-variables-and-objects.md): A deep dive into Python internals, comparing Stack vs Heap memory allocation to C, and understanding how objects and references are managed in memory.
- [Reversing the API Behind the Jeffrey Epstein Files and Building a RAG Bot](https://nirusaki.tech/blogs/reversing-the-api-behind-the-jeffery-epstein-files-and-building-a-rag-bot.md): A deep dive into reverse engineering the U.S. Government's Epstein files database API, bypassing cookie verification, and building a JIT (Just-In-Time) RAG Bot to query terabytes of document data.
- [I Use Arch BTW: The Ultimate Arch Linux Installation Guide](https://nirusaki.tech/blogs/arch-linux-installation-guide.md): A complete step-by-step walkthrough on installing Arch Linux, setting up audio, Bluetooth, graphics, XFCE, Hyprland, Niri, Noctalia dots, and enabling the AUR.
- [Machine Learning: K-Nearest Neighbors (KNN) Explained](https://nirusaki.tech/blogs/machine-learning-knn-algorithm.md): A layman's guide to understanding the K-Nearest Neighbors algorithm, complete with Python code.
- [Cracking OverTheWire: Bandit Walkthrough (Full Run 0-33)](https://nirusaki.tech/blogs/bandit-walkthrough.md): A sick speedrun walkthrough of the ENTIRE OverTheWire Bandit wargame. Levels 0 to 33 baby.
- [DSA Chronicles - Single Linked List Functions](https://nirusaki.tech/blogs/dsa-chronicles-single-linked-list-functions.md): Breaking down the core functions of a Single Linked List in C++.
- [DSA Chronicles - Linked List](https://nirusaki.tech/blogs/dsa-chronicles-linked-list.md): Exploring the fundamentals of linked lists in Data Structures and Algorithms.