Haley Hartin
New York,NY
Summary
Staff Software Engineer specializing in backend and distributed systems, with experience designing high-throughput, event-driven platforms, leading zero-downtime migrations, and building real-time decisioning systems at scale. Technical lead with a track record of defining architecture, driving cross-functional initiatives, and delivering systems with measurable product and operational impact.
Overview
4
4
years of professional experience
Work History
Staff Software Engineer
Current
New York, New York
07.2026 - Current
- Lead the architecture and technical strategy to evolve a card-specific disputes system into a unified, extensible platform supporting 5 dispute types and 1,000+ daily cases, defining shared schemas and event models with type-specific extensions, unified streaming interfaces, and versioned intake workflows that allow new dispute types to integrate without separate lifecycle infrastructure.
- Serve as technical squad lead for 3 engineers, setting engineering direction and coordinating across Product, Compliance, Client Engineering, and Risk Operations to translate business, regulatory, operational, and client requirements into technical strategy and execution.
Senior Software Engineer
Current
New York, New York
12.2023 - 07.2026
- Led the migration of the dispute lifecycle from an outsourced vendor to an internally owned platform, building APIs and automated workflows spanning case management, provisional credit issuance, and real-time agent tooling to bring the end-to-end dispute lifecycle in-house.
- Migrated a live disputes platform handling thousands of daily disputes and hundreds of concurrent agent actions and automated decisions to an event-sourced architecture with zero downtime, using dual writes and shadow reads to validate consistency during cutover and backfilling historical disputes to preserve complete case history.
- Reduced test suite runtime from 2 hours to 6 minutes (~95%) by introducing JUnit parallelism and refactoring shared state and unsafe time dependencies, establishing a pattern subsequently adopted across additional engineering services.
Software Engineer
Current
New York, New York
12.2022 - 12.2023
- Implemented passkey authentication using WebAuthn/FIDO2, integrating credential registration and challenge-response verification into an event-sourced authentication system with auditable auth events, reaching ~70% user adoption.
- Built a Scala pipeline to detect transactions eligible for recovery under Visa network rules and trigger an event-driven workflow that automated chargeback filing with Visa, including validation and failure tracking; automated filings achieved a 99% win rate and recovered tens of thousands of dollars monthly.
- Developed a real-time transaction decisioning platform processing hundreds of thousands of transactions daily under a sub-3-second SLA, using parallel data retrieval and rules-based evaluation to approve, block, or escalate transactions for step-up verification.
Associate Software Engineer
Current
New York, New York
07.2022 - 12.2022
- Implemented sanctions screening across the Know Your Customer (KYC) lifecycle, including real-time onboarding checks and a Scala pipeline triggering daily Office of Foreign Assets Control (OFAC) screening for existing users.
Education
Bachelor of Science - Computer Science
University of Colorado At Boulder
Boulder, CO05-2022
Skills
- API development
- Event-Driven Architecture
- Event Sourcing
- Microservices
- Distributed Systems
- Pub/Sub
- gRPC
- Data Pipelines
Timeline
Staff Software Engineer
Current
07.2026 - Current
Senior Software Engineer
Current
12.2023 - 07.2026
Software Engineer
Current
12.2022 - 12.2023
Associate Software Engineer
Current
07.2022 - 12.2022
Bachelor of Science - Computer Science
University of Colorado At Boulder