Derrick Granowski

Professional Experience

Senior Software Engineer

Current Employment (a Health Company) Dec 2021 — Present
  • Interoperability Architecture: Designed and implemented a next-generation healthcare API based on NIEM 4.0/PMIX 3.0 standards, authoring schemas and documentation for 40+ state integrations.
  • Protocol Proxy: Built a specialized Java-based proxy service implementing NIEM/PMIX model generation via JAXB, XML encryption, and mutual TLS authentication.
  • Platform Modernization: Led the migration to Spring Boot 4 and Java 25, upgrading shared libraries and establishing new microservice patterns adopted across the engineering organization.
  • State-Level Gateway: Architected and built a high-throughput healthcare gateway microservice from scratch as the first production service on the Spring Boot 4 stack.
  • Accessibility Leadership: Drove WCAG 2.1 Level A/AA compliance across core Vue.js applications, remediating 20+ audit findings for screen readers and keyboard navigation.
  • Security & Compliance: Triaged and merged Renovate dependency PRs across 10+ repos; participated in FedRAMP audits and penetration test remediations (CSRF fixes).
  • Infrastructure Optimization: Migrated Docker builds to BuildKit (buildctl) and optimized Kubernetes deployments via Helm/FluxCD for faster CI/CD cycles.
  • High-Throughput Integration: Debugged and fixed cross-state prescription data sharing for multiple US state systems, processing millions of queries.
  • Collaborative Engineering: Regularly co-authored PRs and mentored teammates; authored technical documentation for certificate authentication and secure configuration patterns.
  • Feature Engineering: Developed a next-generation integration API with phased rollout via feature flags and built integrated third-party bed-tracking tools for risk assessment reports.

Software Engineer 3 / Principal

Wide Open West! Aug 2019 — Dec 2021
  • Offshore Leadership: Led an offshore engineering team in delivering a customer-facing self-installation project using C# WebAPI and React/Redux.
  • Infrastructure Modernization: Deployed .NET Core containers to AWS ECS using CloudFormation; rebuilt EC2 hosting infrastructure for improved stability.
  • Authentication Strategy: Aided migration of enterprise services from Okta to OneLogin; educated teams on OAuth and REST abstraction layers.
  • Process Improvement: Introduced the "Deployment Playbook" concept to track downtime window tasks, ensuring safety in production releases.
  • Stakeholder Collaboration: Worked directly with warehouse staff to implement shipment workflows and warehouse vendor REST endpoints.
  • User-Centric Development: Interviewed technicians to gather requirements for improving internal tools and call center web applications.

Technical Lead of Acquisitions

Open Technology Solutions May 2017 — Aug 2019
  • Banking Modernization: Delivered a full rewrite of banking loan applications replacing legacy ASP.NET MVC with .NET Core and React.
  • Security Tooling: Developed a mission-critical AES-256 encryption tool for secure PII data transfer during legacy system deprecation.
  • ADA Initiative: Spearheaded ADA compliance for single-page applications and integrated PDF viewers for customer terms and conditions.
  • Performance Tuning: Resolved API load balancing issues by fixing encryption, proxy, and F5 routing bottlenecks with network engineers.
  • Agile Transformation: Guided legacy developers into modern Agile practices, driving planning sessions and establishing team velocity.
  • Legacy Migration: Built batch processes to migrate the company from unmaintainable web apps to a partner's new framework.

Sole In-House Lead Developer

PayReel / CrewConnection May 2016 — May 2017
  • Practice Building: Established internal development practices and CI/CD pipelines from scratch for a small team.
  • Third-Party Integration: Led integration of ASP.NET MVC systems with ADP REST APIs and implemented Google Analytics for client portals.
  • Protocol Security: Secured internal payroll tools using OAuth 2.0 and JWT protocols to prevent unauthorized business logic access.
  • Infrastructure Consolidation: Brought source code in-house from multiple contractors and established centralized Git source tracking.
  • Database Optimization: Optimized T-SQL queries and upgraded object mapper dependencies (LLBLGen) for the staff portal.
  • Product Advocacy: Incorporated support staff into the design process by gathering requirements for report adjustments.

Earlier Career Experience

TurboAppeal | Lead Full-Stack Developer 2015 — 2016
  • MVP Delivery: Successfully deployed the initial customer onboarding portal for Series A funding release.
  • Payment Integration: Integrated Braintree payments and Google Analytics using AngularJS 1.5 and Bootstrap 3.
  • SEO Optimization: Improved organic search performance via robots.txt management and Twitter card metadata integration.
  • Technical Mentorship: Coached junior developers and established remote development practices for a distributed team.
Food Service Warehouse | Mid-Level Engineer 2014 — 2015
  • Build Automation: Configured a custom Jenkins Linux build server to automate C# and Node.js application deployments.
  • Shared Tooling: Extracted 3rd-party fraud integration logic into a shared, versioned NuGet library.
  • Shipment Tracking: Developed a green-field AngularJS front-end for real-time customer shipment tracking.
  • Linux Administration: Managed CentOS server security via firewalld and optimized Node.js service configurations.
  • Vendor Integration: Led technical communications with 3rd-party vendors to improve automated forecasting software.
Sansio / Physio Control | Software Developer 2011 — 2014
  • Mobile Healthcare: Developed a cross-platform mobile medical app for onsite patient data collection using VB.Net and ASP.NET.
  • Data Sync: Built complex medication synchronization logic using Backbone.js, jQuery, and JavaScript promises.
  • Infrastructure Refactoring: Overhauled the reporting system, reducing production hot-fixes from daily to weekly.
  • Claim Systems: Implemented specialized web interfaces for standardized medical claim forms (UB04, CMS-1500).