Hi, my name is

Software Engineer

Im a frontend software engineer with 2+ years of experience in performance-critical web development, specializing in React/Next.js and server-side rendering. I work mainly in fintech and payments — shipping fraud-prevention, compliance, and performance-optimization features for high-traffic products.

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Portrait of Qalbun Salim

Professional Experiences

Traveloka

Software Engineer - Paylater

Jan 2025 - Present

  • Cut repayment page LCP by ~60% (5.2s → 2.1s) and CLS by ~77% (0.2541 → 0.0578) via server-side rendering.
  • Led partial repayment frontend, validated by A/B test (2.79% → 3.22%) for a 15.45% relative uplift in repayment rate.
  • Built an authentication challenge module embedding dynamic PIN, OTP & NIK checks in a webview to deter fraud across Paylater flows.
  • Built a subledger transaction visualization tool, cutting check time by 90%.
  • Implemented Android digital signature for offline payments to meet OJK compliance.
  • Built AI-driven live browser testing with Claude subagents to verify code changes.

Software Engineer Intern - Corporate Travel

Feb 2024 - Dec 2024

  • Revamped the B2B Corporate Travel landing page with a dynamic marquee showcasing 2,000+ partner companies.
  • Redesigned admin company-management UI, unifying Travel Policy, Employee List, and Approval System into one streamlined workflow.

Universitas Indonesia

Automata Theory Teaching Assistant

Aug 2022 - Jan 2023

  • Graded homework for 23 students across finite state machines to Turing machines.
  • Mentored 5 students with weekly lessons and exam prep on automata theory.

Toolbox

What I work with

The higher a tool sits, the more I reach for it. Core, comfortable, learning.

Core · daily drivers

Comfortable · steady

Learning · sharpening

no bars · no ratings · just how it lives in my day

Featured Projects

Things I’ve built and continue to explore

CopyFlow

2025

CopyFlow

Automated copywriting workflow in Lark — from first draft to launch.

Team entry to Traveloka's 2025 Lark Efficiency Pioneer Competition. CopyFlow replaces manual copywriting handovers with a single automated Lark workflow: a Figma link populates a Lark Base as the source of truth, an LLM co-pilot keeps every draft on-brand, and approval-triggered automation delivers translated, locale-ready copy to POEditor and in-house content tools.

  • Figma link populates a Lark Base as the single source of truth
  • LLM co-pilot keeps every draft consistent with company tone standards
  • Approval-triggered handoffs with AI translation across all locales
Lark
Automation
LLM
Amazon Bedrock
Chess PTP

2025

Chess PTP

Play chess peer-to-peer over WebRTC — local or online, no game server.

A web chess app with both local and online modes. In online multiplayer, two players connect directly over WebRTC: a host generates a game code and shares it for a guest to join, and moves travel peer-to-peer through a data channel instead of a game server. Firebase Firestore is used only for signaling (exchange of the connection offer and ICE candidates), and moves are validated on both sides with host authority for conflicts.

Vue
Vite
TypeScript
chess.js
WebRTC
Firebase

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