BINTANG YOSUA

Freelance Project Manager & AI Engineer

• Led a 5-person cross-functional team building a B2C health super-app on 13 Go microservices, running Scrum ceremonies, backlog grooming, and code reviews.
• Negotiated pricing and scope with stakeholders, and designed a subscription model backed by a per-feature AI cost model, securing a ~63% gross margin even at full quota usage.
• Drove the payment gateway migration from Xendit to Flip in 2 weeks, cutting bank-transfer fees by 72% and retail payment fees by 50%.
• Built 3 production AI features on Google Gemini with 97–98% recognition accuracy, reducing per-scan inference cost by ~65% and response time from 12s to 2–3s.

Freelance Software Engineer

• Initiated the backend migration from NestJS to Go (Echo) microservices, reducing API response times by ~85%.
• Built a Playwright E2E test suite of 300+ test cases in CI, replacing manual regression testing.
• Developed Next.js and SvelteKit platforms serving 1,500+ users, and 4 core features including a payment gateway.

Freelance Software Engineer

• Delivered 5 client projects (Next.js, NestJS, Laravel, Flutter) with a 100% on-time delivery rate on 1–3 month timelines.

Fullstack Developer Intern

• Developed an application to track 200+ computers across all departments for practicum sessions
• Transformed a manual paper- and whiteboard-based system into a digital solution, cutting administrative tracking time and complexity

Quantitative Researcher, Developer & Trader

• Built an automated Rust/Golang trading system that monitors the top 50 cryptocurrencies on Binance and Bybit, running 4 backtested strategies 24/7.
• Validated the strategies using Monte Carlo simulation and Sharpe and Sortino ratios before executing live trades.

Head of IT Support

• Led a team of 2 and managed a Discord community of 1,000+ members.
• Operated technical setup for English learning sessions, events, and meetings to ensure smooth delivery