Software Developer · Mentor · Problem Solver

Hollen Graver

I build resilient software that powers real businesses. From the JVM, C#, and Go services to Angular front-ends, I focus on clean architecture, measurable impact, and empowering teams through mentorship.

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Summary

What I bring

A decade of experience shipping production software and leading high-impact initiatives. I specialize in bridging robust backend services with intuitive user interfaces, with a focus on scalable platforms, developer enablement, and agentic AI workflows. Outside of work, I'm a technical tinkerer and mentor, exploring the frontiers of local LLMs and emerging AI tools.

Experience

Impactful roles

Campspot · Senior Developer Level 2 Java · Kotlin · Angular

Mar 2024 – Present

  • Tech Lead for the design and implementation of a complex 'Abandoned Cart' recovery system, orchestrating cross-domain workflows across distributed services to drive revenue recovery.
  • Implemented fraud mitigation strategies that eliminated carding attacks, ensuring long-term transaction security and reducing business risk.
  • Mentor junior and mid-level developers through architectural guidance and rigorous code reviews, directly contributing to their promotion to senior levels.
  • Lead the development and maintenance of the customer-facing mobile application using Flutter.

Campspot · Senior Developer Level 1

Apr 2022 – Mar 2024

  • Designed and deployed a comprehensive gift card platform adopted by a majority of clients, significantly expanding customer engagement and revenue opportunities.
  • Managed and optimized payment processing systems handling millions of dollars in daily transactions.
  • Built critical in-house Point of Sale (POS) and invoicing systems essential to daily campground operations.
  • Drove UX-centered feature improvements that contributed to a measurable increase in Net Promoter Score (NPS) and improved customer retention.

Campspot · Developer Level 2

Jul 2019 – Apr 2022

  • Owned the implementation of enterprise-level discount and promotional code management systems across multiple concurrent park environments.
  • Contributed to the strategic migration of core features from a legacy Node.js/TypeScript backend to a scalable Java backend.
  • Collaborated on cross-functional feature rollouts, improving overall system functionality and stability.

PRSM Healthcare · Software Engineer C# · .NET · Systems Design

Jun 2014 – May 2019

  • Engineered a fault-tolerant system using redundant VPN connections and load balancing to ensure 100% uptime for critical call center infrastructure.
  • Facilitated a 2x increase in client capacity by developing scalable web and data solutions while maintaining operational stability.
  • Led the complete rewrite of the core B2B business application, migrating the codebase from PHP to C# ASP.NET.
  • Orchestrated the full-scale migration of business applications from on-premises infrastructure to Microsoft Azure and ultimately to AWS.
  • Integrated complex customer outreach software with VoIP technologies based on FreePBX.

Skills

Full-stack toolkit

Languages

Java · Kotlin · TypeScript · JavaScript · Go · Python · C# · Dart

Frameworks

Angular 2+ · AngularJS · Flutter · .NET Core · ASP.NET · Quarkus · Dropwizard

Data & Search

PostgreSQL · MySQL · SQLite · Elasticsearch · OpenSearch · Redis · Valkey

DevOps & Infra

AWS · Docker · Kubernetes (K3s) · ArgoCD · Prometheus · Grafana · Load Balancing

Core Engineering

Fault-Tolerant Design · REST API Design · TDD · Clean/Onion Architecture · Mentorship

AI & ML

Llama.cpp · LLM Agents · MCP · Agentic Coding · Local Model Deployment · Prompt Engineering

Education

Mansfield University of Pennsylvania

B.Sc. Computer Information Science

Information Systems focus · Graduated 2014