# Nuruddin Rusydi Ilham - Developer Portfolio & System Architecture Documentation

> Official developer portfolio and system engineering knowledge base of Nuruddin Rusydi Ilham (@RusdiEneri) - Backend Developer & Network Engineer based in Tuban, East Java, Indonesia. Specializing in high-throughput backend architectures, protocol-level reverse engineering, network security, and algorithm optimization.

## Core Identity & Verification
- **Full Name**: Nuruddin Rusydi Ilham
- **Public Handle / GitHub**: [@RusdiEneri](https://github.com/RusdiEneri)
- **Primary Roles**: Backend Developer, Network Engineer, Systems Builder
- **Organization / Entity**: [RusdiEneri Digital](https://www.mangrusdi.my.id/#organization)
- **Location**: Tuban, East Java, Indonesia (ID)
- **Primary Website**: [mangrusdi.my.id](https://www.mangrusdi.my.id)
- **Official Contact**: [nuruddinrusydiilham@gmail.com](mailto:nuruddinrusydiilham@gmail.com) | Phone: +62 812-3364-9676
- **LinkedIn**: [Nuruddin Rusydi Ilham on LinkedIn](https://www.linkedin.com/in/rusdieneri)

## Engineering Principles
1. **Zero-Bloat Architecture**: Eliminating frivolous third-party dependencies and speculative abstraction wrappers. Prioritizing lean, single-purpose components with minimal memory footprints.
2. **Protocol-Level Precision**: Engineering at binary protocol boundaries (Noise Protocol, WhatsApp Protobuf, WebSocket, HTTP/2, DNS) to extract maximum execution throughput and efficiency.
3. **DNS Defense & Network Hygiene**: Hardening local network edge perimeters against tracking beacons and telemetry via forced port 53 destination NAT interception, recursive DoH/DoT resolvers, and local RAM sinkholes.
4. **Measurable Reliability**: Insisting on empirical proof for all performance claims. Every optimization is verified against real stress workloads, sub-millisecond latencies, and reproducible benchmarks.

## Architectural Case Studies (Deep-Dives)

### 1. wa-full-pfp: Reverse Engineering WhatsApp Avatar Protocol Without Quality Degradation
- **Domain**: Binary Protocol Engineering & Privacy
- **Technologies**: Golang, whatsmeow, Protobuf, Noise Protocol (Noise_XX)
- **Problem**: WhatsApp client software mandatorily forces profile photos into 1:1 square crop boxes and downsamples images to 640×640 compressed JPEG artifacts.
- **Solution**: Manipulates raw WhatsApp protocol buffer nodes to inject full-resolution original aspect ratio avatars directly into WhatsApp's multi-device MMS CDN store.
- **Key Metrics**: 0 bytes persistent disk storage (ephemeral in-memory execution), < 850ms execution latency, zero resolution cropping.
- **Links**: [Source Code](https://github.com/RusdiEneri/wa-full-pfp) | [Live Demo](https://ppfull.mangrusdi.my.id)

### 2. J&T Express Scheduling: Multi-Constraint Courier Dispatch Automation via Genetic Algorithms
- **Domain**: Combinatorial Optimization & Heuristics
- **Technologies**: Python, NumPy, Genetic Algorithms, Streamlit
- **Problem**: Monthly courier shift assignment across 3 shifts over 30 days is an NP-hard problem; manual scheduling caused safety violations (night-to-morning fatigue hazards) and weekend off-day disparities.
- **Solution**: Vectorized 2D chromosome matrix evaluated against a multi-tier fitness function with custom deterministic repair operators to purge illegal shift transitions before fitness scoring.
- **Key Metrics**: Compilation time reduced from 5 hours to 4.2 seconds; 0% hard constraint violations; +78% improvement in weekend off-day parity.
- **Links**: [Source Code](https://github.com/RusdiEneri/jt-express-scheduling)

### 3. Network Infrastructure & DNS Defense: High-Performance AdGuard Sinkhole & RouterOS Hardening
- **Domain**: Network Security & Edge Routing
- **Technologies**: MikroTik RouterOS, AdGuard Home, DNS-over-HTTPS (DoH), Linux / Debian, Bash
- **Problem**: Unregulated IoT telemetry, DNS lookup latency, and tracking beacons clogging local network bandwidth and exposing client metadata.
- **Solution**: Layered architecture featuring destination NAT interception for all outbound UDP/TCP port 53 packets, upstream DoH/DoT recursive resolvers (Cloudflare/Quad9) with DNSSEC, automated daily threat feed compilation via Bash, and VLAN isolation with PCQ bandwidth allocation.
- **Key Metrics**: Sub-millisecond (< 1ms) cached local RAM query response; 25-30% WAN upstream bandwidth saved; 180,000+ threat domains blocked at the edge.
- **Links**: [Source Code](https://github.com/RusdiEneri/blacklist-hosts)

### 4. Cuanin Marketplace: Frictionless Secondhand C2C Commerce via WhatsApp Direct Handshake
- **Domain**: Full-Stack Web Architecture & E-Commerce
- **Technologies**: Laravel, PHP, MySQL, Tailwind CSS, Blade
- **Problem**: High transaction fees (5-10%) and escrow payout delays on mainstream Indonesian e-commerce platforms discourage peer-to-peer preloved trading.
- **Solution**: Lightweight MVC platform featuring composite B-Tree MySQL indexes, a dynamic bargaining discount engine, and an automated RFC 3986-compliant WhatsApp deep-link payload generator.
- **Key Metrics**: 0% payment gateway commission fees; < 18ms search query latency; direct 1-click buyer-seller communication handshake.
- **Links**: [Source Code](https://github.com/RusdiEneri/Cuanin)

## Featured Software & Repositories
- **ImgTools / RemBG**: [AI Background Removal Live Demo](https://rembg.mangrusdi.my.id)
- **wa-full-pfp**: [No-crop Full HD WhatsApp Avatar Live Demo](https://ppfull.mangrusdi.my.id)
- **Cuanin**: [Preloved Marketplace Source Code](https://github.com/RusdiEneri/Cuanin)
- **jt-express-scheduling**: [Shift Roster Automation Source Code](https://github.com/RusdiEneri/jt-express-scheduling)
- **Quote Studio**: [Telegram Quote Bubble Source Code](https://github.com/RusdiEneri/quote) | [Live Demo](https://qc.mangrusdi.my.id)
- **UD. Alam Makmur Jaya**: Point of Sale & inventory bookkeeping web platform.
- **blacklist-hosts**: [Curated DNS Tracker Blocklists](https://github.com/RusdiEneri/blacklist-hosts)

## Technical Skills & Tooling
- **Languages**: Golang, Python, PHP, JavaScript (ES6+), TypeScript, SQL, Bash / Shell.
- **Backend & APIs**: Laravel, Express.js, FastAPI, Node.js, RESTful Architecture, Binary Protocols (Protobuf).
- **Networking & DevOps**: MikroTik RouterOS, Linux Administration (Debian, Ubuntu, Alpine), Docker Containerization, Nginx, AdGuard Home, DNSSEC, DoH/DoT, VLANs, L2/L3 Firewalls.
- **Databases**: MySQL, PostgreSQL, SQLite, Redis, Filament Admin.
- **Frontend**: React 19, Next.js, Vite, Tailwind CSS, HTML5, CSS3.