Boyu Fang

Senior Software Engineer

Instagram Relevance Labs — Founding engineer & tech lead, “Tune Your Algo” (2024–Present)

• Designed and built the first end-to-end prototype of Tune Your Algo and defined the long-term architecture for user-controllable recommendations on Instagram.
• Led a cross-functional team of ~10 engineers across ranking, infra, and product from incubation to large-scale rollout.
• Shipped Tune Your Algo to all English-speaking users (~1.7 billion people) — Meta’s first AI-powered system letting users explicitly steer the recommendation algorithm at scale.
• Drove alignment with senior leadership, securing investment and headcount via the product vision, technical strategy, and projected impact.
• Established internal best practices for user-controllable recommendation systems (controls, telemetry, safety), used as a reference by other relevance teams.

Instagram — Reposts ranking & infrastructure (H1 2024)

• Led core ranking and infrastructure for Instagram reposts as part of new “Friends” experiences, contributing to nearly 1% core session growth on IG, especially among teens.

Instagram — Feed Relevance infrastructure (2022–2023)

• Designed and implemented an internal ranking DSL and interpreter used across Instagram Feed Relevance.
• Optimized feature fetching during inference and training-data logging, reducing latency and infra cost.
• Cumulatively saved >1000 ms of latency and >1 MW of power across Instagram Feed infrastructure.
• Improved sourcing and delivery components of the feed system for better efficiency and reliability.

Featured in The Verge, Mashable, ABC News, and Meta Newsroom; highlighted by Adam Mosseri (Head of Instagram).

Senior Software Engineer, Business Integrity

• Redesigned the policy search tool to surface the most relevant policies per query — 90% of user clicks landed on the first page of results.
• Built a data-driven policy iteration process with policy insights and policy-simulation A/B testing tools.
• Led a major refactor of the policy-management backend for reliable, low-risk policy updates.

Quant / Senior Developer — Bloomberg, Citadel, Millennium, Squarepoint

• Squarepoint — Built a U.S. power-grid simulation platform letting quants run tens of thousands of FTR scenarios per day to support trading decisions.
• Millennium — Built from scratch a macro trading research and production stack (signals, portfolio construction, backtesting) for a new systematic team, supporting hundreds of strategies in production.
• Citadel (Global Fixed Income) — Implemented a real-time live P&L framework, cutting production incidents ~50% and improving P&L latency for traders and risk.
• Bloomberg (FXGO) — Engineered core components of Bloomberg’s FXGO institutional FX trading platform, focused on low latency and reliability.