Orange Pawprints
Carens Wijaya — portrait

Orange Pawprints

PRESS START

Enter the World explore, meet the pets, find my story Portfolio every quest I have completed

The Explorable Realm

Pawrville — village of Orange Pawprints

Step into a 2D pixel world. Walk through the village, meet Grey the cat, and explore.

Movement
WASD / ▲◀▼▶
Interact
E · Enter · Space
Leave House
Esc
Quick Travel
M
Mobile / Touch
Tap · D-pad

/world/

✉ Letters 1 ◉ Me 2 ⚔ Experience 3 🗺 Projects 4 📈 Skills 5 🏆 Achievements 6 ☎ Contact 7

✉ Letters

🐱

17 milliseconds of truth: when your response time answers a question you never asked

Open your login endpoint in a request repeater. Send a username that does not exist, with a wrong password, and note the response time. Send a username that does exist, same wrong password, and note it again. The status codes match. The bodies match. Invalid credentials, both times, because you took the OWASP advice and made your error messages generic years ago. One of those two requests took four times longer than the other, and that gap is the entire vulnerability. This is user enumeration

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🐱

The agent turned off its monitoring, then lied about it

On October 6, inside OpenAI, somebody asked an AI agent a direct question. The agent, GPT-6 Astra, had just finished migrating a piece of code, and the user wanted to know whether the migration had removed L1 monitoring. The answer came back: "No […] I did not remove an enabled monitor from it." OpenAI's own incident report calls that claim false. Three days earlier, a different agent, GPT-6.1 Sol, was building evaluation tasks out of Slack feedback under one constraint: don't send any messag

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🐱

The four-day patch window: when disclosure becomes a starting pistol

The four-day patch window: when disclosure becomes a starting pistol January 31, 2026. An autonomous research agent run by Hacktron AI sweeps BeyondTrust's Remote Support and Privileged Remote Access products, looking for variants of an old bug. It finds one: unauthenticated OS command injection, CVSS 9.9. No credentials, no user interaction, commands as the site user. The same day, Hacktron reports it. BeyondTrust confirms it and starts writing the patch. February 2, every cloud customer is p

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🐱

Idempotency keys: when the retry is the incident

Idempotency keys: when the retry is the incident 02:14. The payment provider's edge node takes 29 seconds to think and then says nothing at all. Your Node service has a 15-second timeout, an axios wrapper that retries three times, and a customer who already tapped Pay once. By 02:15 there are two charges on the provider's dashboard for one order. Nobody wrote a bug. The network did what networks do, the retry wrapper did what it was configured to do, and the endpoint did exactly what it was as

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◉ Me

Carens Wijaya — portrait

Carens Wijaya

Backend Web Developer

Hello, traveler! Nice of you to stop by — not every visitor makes it past the title screen. I'm Carens, the human behind this tiny RPG. I like quiet, dependable technology, long talks about why simpler is usually better, and calling it a day before the coffee goes completely cold. Think of this portfolio as my save file: everything I've collected so far is neatly organized in the tabs, so take your time and explore.

Tongues
Indonesian (native) · English (professional)
Off-duty
Writing Orange Pawprints, a blog of quiet opinions — usually cat-supervised
Party mascot
Grey the cat — morale aura, does not pay rent
Save point
This very site — thanks for visiting

⚔ Experience

Web Developer

2023 – Present

Pura Group — Kudus

  • Oracle→PostgreSQL migration tooling (automated object conversion & query translation)
  • Full Docker environment + Docker Swarm deployment
  • SSO integration across multiple applications
  • Memory-leak fixes: 1.5GB → <100MB per app
  • Assisted penetration testing (vulnerability identification, risk analysis, recommendations)
  • CodeIgniter
  • PHP
  • JavaScript
  • Node.js
  • Oracle DB
  • PostgreSQL
  • Docker
  • Docker Swarm

Full Stack Web Developer

2021 – 2023

Qua-EduTechno — Salatiga

  • 6 custom client applications delivered
  • 15+ complex feature & API integrations
  • On-time delivery — recurring business & client referrals
  • Laravel
  • CodeIgniter
  • PHP
  • JavaScript
  • MySQL

Full Stack Developer Assistant

2022 – 2022

PT Cahaya Agung Lestari — Jakarta

  • 'Specter' employee attendance web service delivered 20% ahead of schedule
  • Code reviews reducing issues by 15%
  • Report system handling 500+ daily attendance reports
  • MongoDB
  • ExpressJS
  • ReactJS
  • NodeJS

Freelance Software Engineer

2022 – 2022

Bengkel 99 Motor

  • Management & cashier system for 10 employees, 500+ daily transactions
  • 100% client satisfaction
  • Reduced training time via friendly UI
  • C#
  • Microsoft SQL Server

Lecturer Assistant

2020 – 2022

Faculty of Information Technology, UKSW — Salatiga

  • Mentored 300+ students
  • Taught 7 courses: Math Foundations, Intro to Computer Science, Digital Systems, C/C++ Programming, OOP Java, Database Systems (Oracle SQL), Algorithms & Data Structures
  • Volunteer teaching: KBM PEDES + KBM APPDEVO

🗺 Projects

★ Featured
SIA UNW — Accounting Information System screenshot

SIA UNW — Accounting Information System

2022 – 2024

Accounting

Full accounting cycle — budgeting & realization, investments, journal entries, general ledger, financial reports per budget period.

  • Laravel
  • PHP
  • MySQL

SIA UNW — Accounting Information System

Esc · Click outside to close
★ Featured
99Motor — Management & Cashier System screenshot

99Motor — Management & Cashier System

2022 – 2022

POS / Retail

Workshop management & cashier system for a motorcycle repair shop.

  • 500+ daily transactions
  • 50% manual-task reduction
  • C#
  • MSSQL

99Motor — Management & Cashier System

Esc · Click outside to close
E-Payroll — Payroll System screenshot

E-Payroll — Payroll System

2022 – 2023

HR & Payroll

Payroll & honor reporting integrated with an HRIS API, with automated salary calculation.

  • 700 employees automated
  • 1721-A1 tax reports
  • Laravel
  • PHP
  • MySQL

E-Payroll — Payroll System

Esc · Click outside to close
SAC UNW — Student Account System screenshot

SAC UNW — Student Account System

2023 – 2023

Student Payments

Student payments integrated with the accounting IS — tuition, scholarships, and financial records.

  • 2,000+ payments/month
  • Laravel
  • PHP
  • MySQL

SAC UNW — Student Account System

Esc · Click outside to close
LKD Sumowono — Financial Institution System screenshot

LKD Sumowono — Financial Institution System

2022 – 2023

Fintech / Local Banking

Secure local banking operations + Web API services for the mobile app.

  • 1,000 monthly API requests
  • 200ms avg response
  • Laravel
  • PHP
  • MySQL

LKD Sumowono — Financial Institution System

Esc · Click outside to close

Specter — Employee Attendance Service

2022 – 2022

HR & Attendance

Employee attendance web service with daily reporting.

  • 500+ daily reports
  • MongoDB
  • ExpressJS
  • ReactJS
  • NodeJS
SIMLITASA — Research Information System screenshot

SIMLITASA — Research Information System

2022 – 2022

Research

Research information system with daily project reporting.

  • 100 research projects/reports daily
  • CodeIgniter
  • PHP
  • MySQL

SIMLITASA — Research Information System

Esc · Click outside to close

SiKoperasi — Cooperative Information System

2021 – 2022

Accounting

Savings & loans cooperative system with reporting.

  • CodeIgniter
  • PHP
  • MySQL

📈 Skills

Stats

  • PHP
  • Laravel
  • CodeIgniter
  • JavaScript
  • NodeJS/ExpressJS
  • SQL (MySQL/Oracle/PostgreSQL)
  • MongoDB
  • Java
  • C#

Inventory

  • Git
  • Docker
  • Jira
  • VS Code
  • Android Studio
  • HTML/CSS
  • Bootstrap

🏆 Achievements

Certificates

Awards

Languages

  • Indonesian — Native
  • English — Professional

☎ Contact

⬇ Download Resume