Mike Hall

Staff Software Engineer / Systems Architect
Chicago, IL  |  Email: mike@just3ws.com  |  Phone: (847) 877-3825  |  Website: https://www.just3ws.com  |  LinkedIn: https://www.linkedin.com/in/just3ws/  |  GitHub: https://github.com/just3ws

PROFESSIONAL SUMMARY

Staff Software Engineer specializing in high-consequence legacy modernization, distributed systems architecture, and platform resilience. Combines hands-on software engineering with platform architecture, OpenTelemetry distributed tracing, cross-lane boundary mediation, and zero-downtime data migrations across Ruby on Rails, PostgreSQL, and cloud infrastructure.

CORE SKILLS

Platform Architecture & Legacy Modernization, Cross-Domain Boundary Architecture & Governance, OpenTelemetry & Distributed Trace Context Propagation, High-Consequence Incident Escalation & Root Cause Analysis, Zero-Downtime Data Migrations & Schema Partitioning, Ruby on Rails, PostgreSQL, Sidekiq & Redis, AWS, Docker, Kubernetes & CI/CD Pipelines, Privacy-Conscious Local AI Orchestration & Tooling

EXPERIENCE

ASSOCIATE DIRECTOR, STAFF ENGINEER
OneMain Financial
Remote | January 2021 - February 2026

Led modernization of the Acquisition Lane, the digital front door for customer application and origination funnel workflows, delivered an instant disbursement workflow, applied Architecture Discovery to a silent application-completion defect, and aligned distributed observability with SRE operations.

SENIOR BACKEND DEVELOPER
SK Holdings, Inc.
Chicago, IL | January 2019 - December 2020

Modernized search and asynchronous messaging pipelines under live production load, executing zero-downtime Rails framework upgrades and database relational indexing.

SENIOR SOFTWARE DEVELOPER
ActiveCampaign
Chicago, IL | September 2018 - December 2018

Improved testability and performance inside a tightly coupled PHP/MySQL CRM backend, introducing structured query patterns and cache strategies, and hardening the Ember.js frontend test suite across core contact management workflows.

SOFTWARE ENGINEER & TECHNICAL ONBOARDING LEAD (FRAUD & TAXONOMY SYSTEMS)
Groupon
Chicago, IL | July 2011 - May 2013

Implemented a centralized merchant taxonomy service in Java and MySQL, engineered analytical fraud detection in Vertica, and led global technical onboarding curricula during hyper-growth.

ADDITIONAL EXPERIENCE

Senior Software Developer | BenchPrep (March 2017 - February 2018)
Owned enterprise assessment workflows, leading correctness and platform security in a high-concurrency environment.
Senior Software Developer | ReachLocal (March 2015 - November 2016)
Owned API design and modernization strategy, leading incremental legacy migration for a high-volume digital marketing platform.
Open-Source Transition Lead | Coderwall (January 2014 - December 2014)
Hired as a contractor by the founder to lead the open-source transition of the Coderwall developer reputation platform, a Y Combinator-backed professional network for software engineers (856 GitHub stars, 304 forks). Delivered security hardening, proprietary service extraction, infrastructure modernization, and community leadership as the top contributor to the open-source codebase.
Principal Consultant | Tandem (August 2018 - August 2018)
Conducted an on-site architectural and operational assessment for an at-risk federal software program (DoD MEPS), delivering viability analysis and risk mitigation recommendations directly to executive leadership.

EARLIER EXPERIENCE

Built and operated enterprise integrations, transactional systems, and early web products across consulting and product organizations, establishing the production discipline and community-centered craftsmanship that inform my leadership today.

Revenue-critical commerce: Designed real-time inventory, locking, and fulfillment services for a high-volume ticket marketplace later acquired by a major industry operator.
Consulting and software craftsmanship: Delivered systems across client environments while mentoring engineers, adopting Ruby and Rails, and helping build Chicago's craftsmanship community.
Enterprise and operational systems: Built integration and operational software across large organizations, grounded in .NET, SQL, messaging, production support, and direct user needs.