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Experience

experience.md › git log --graph

Experience

  1. Senior Backend Engineer, Rektstudios, full-time HEADpromoted

  2. Senior Backend Engineer, Rektstudios, part-time

    Nov 2024 – Present, 1 year 11 months, full-time, remote

    Sep 2024 – Nov 2024, 2 months, part-time, remote

    • One of the founding backend engineers (team of 3). Co-built Rekt Game Core from scratch, a NestJS backend for auth, wallet, store, marketplace, game orchestration, XP and level progression, battle pass, and referral reward. HTTP serves clients, RabbitMQ talks to other services, BullMQ on Redis runs workers. We took it from zero to 10k+ registered players and 17k+ SpludgeWars matches played. Reviewed code within the team
    • Partnered with a blockchain developer on wallet flows and on-chain withdrawals. Together we built NFT minting and on-chain reward transfers. Consumed RabbitMQ indexer events for purchases and order fills. Coordinated with the game and frontend teams
    • Built a wallet ledger for off-chain credit and custodial ERC-20. Internal transfers stay off-chain, withdrawals settle on-chain. Hardened writes with Postgres advisory locks, CAS status transitions, and idempotency keys
    • Built store purchases across off-chain, custodial, and self-custody wallets. Rekt Game Core credits the custodial ledger on failed or refunded on-chain payments
    • Unified WEB2 and WEB3 trading on a marketplace. WEB2 fills settle as buyer debit, NFT ownership, seller credit. WEB3 fills arrive from Envio on RabbitMQ and a job applies it
    • Built battle pass rewards (tokens, inventory-first NFTs, tickets, XP boosts) and a shared reward grant pipeline for battle pass and referral reward with idempotent wallet jobs
    • Added Rekt Game Core auth with JWT, 2FA, email and phone verification, SIWE, and OAuth (Google, Snapchat)
    • Built uncapped XP and level progression and a realtime leaderboard (account and character, daily through all-time), with 3-month seasons run by queue jobs
    • Co-built Rekt Game Chat from scratch, a NestJS service (GraphQL + Socket.IO, Redis adapter). It handles DMs, public/private/global groups, friends and blocking, typing indicators, and multi-device presence. Global groups allow guests

    2 files changed rektstudios-core.mdrektstudios-chat.md

  3. Lead Engineer, Kadence International promoted

  4. Senior Backend Engineer, Kadence International

    Jan 2024 – Nov 2024, 10 months, full-time, hybrid

    Jul 2021 – Dec 2023, 2 years 5 months, full-time, hybrid

    • Built Kadence Kepo (Jul 2021 – Dec 2021), Kadence's field-operation app for its registered shoppers. Built the backend, the Android app and the infrastructure, while a teammate built the web dashboard's front end. Served 1k⁠–⁠2k users and ran 3 fieldwork projects at once, with 50 MB chunked uploads
    • As the first engineer, interviewed the internal users and benchmarked other apps, then designed and led K-⁠OINS (Jan 2022 – Nov 2024), Kadence's survey and panel app on the App Store and Google Play. Built its Flutter app and its 4 NestJS microservices on MongoDB. They share a backend with Kepo and talk only through RabbitMQ
    • Replaced a vendor app that cost IDR 780⁠–⁠900M in its first year (IDR 300M to build, IDR 20M a month in maintenance, IDR 20⁠–⁠30M a month for servers and services). Built in-house, K-⁠OINS cost about IDR 540M less in its first year, about 60–69% lower than the vendor, and IDR 240M less a year after. The in-house build paid for itself in the first year
    • Rated 4.2 (84%) on the App Store and 3.6 (72%) on Google Play (the vendor app it replaced scored 2 and 1), with 18k registered panelists, about 2k (11%) active monthly, and 2–3 surveys a week
    • Rate-limited to 100 answers per second so the small servers do not fall over. Xendit withdrawals total up to IDR 5M a month, at most IDR 300K per panelist
    • Led Internal Tools, a NestJS and Next.js expense platform for multi-workspace claims, purchase orders, reimbursements, and settlements with S3 uploads and PDF export
    • Led the team of 1 web front-end engineer, 1 designer and 2 interns. Set the design and technical direction and mentored the interns. Owned the service architecture and CI/CD with GitHub Actions from the start and Docker deploys

    3 files changed kadence-k-oins.mdkadence-internal-tools.mdkadence-kepo.md

  5. Associate Fullstack Engineer, Gradana Indonesia

    Mar 2020 – Jul 2021, 1 year 4 months, full-time, on-site

    • Migrated a monolith to microservices in stages on a live production system
    • Designed Alibaba Cloud compute, networking, and storage for web and mobile
    • Set up Jenkins CI/CD and automated tests
    • Supported OJK (Otoritas Jasa Keuangan) certification for Gradana, a P2P lending platform

  6. Backend Engineer, Gtech Digital

    Apr 2019 – Mar 2020, 11 months, full-time, on-site

    • Built and maintained MAP Loyalty System APIs, a multi-tenant loyalty platform for iOS, Android and web clients
    • Turned product requirements and user stories into workflows and API contracts
    • Designed and tuned NoSQL and MySQL schemas for loyalty transactions with high-frequency reads and writes
    • Diagnosed production incidents through the ticketing system
    • Owned MAP Loyalty System maintenance. Handled monitoring, hotfixes, and performance tuning

  7. Backend Engineer, Kepo Solusi Indonesia initial commit

    Oct 2018 – Apr 2019, 6 months, full-time, on-site

    • Built REST APIs for web and mobile clients
    • Designed workflows from business and technical requirements
    • Designed databases and tuned query performance