Andrew Castor
Infrastructure & Security Engineer
U.S. Citizen · Eligible for Security Clearance
Summary
Infrastructure and security engineer with 2+ years deploying healthcare IT and secure networks in production and austere field environments. Built end-to-end offline-capable EMR systems, hardened access controls, and trained 50+ users. CompTIA Security+ and Network+ certified. Pursuing B.S. Information Technology at UCF (NSA CAE-CD) with accelerated M.S. Cyber Security & Privacy track. Targeting cybersecurity, cloud, and information security analyst roles.
Experience
Lead Systems Engineer / Implementation Lead
2023 – PresentMedical Missionaries of Divine Mercy·Houston, TX·Case Study ·Field Journal ·MMDM.org
Clinics
Intake Delay ↓
Users Trained
Patients Served
Security & Infrastructure
- Rebuilt OpenEMR 7.0.x on Ubuntu 22.04 / Apache / MariaDB 10.6 / PHP 8.1 after diagnosing an AJAX/JSON failure rooted in globals.php; chose full rebuild over patch to eliminate latent config drift.
- Built private Certificate Authority and signed server certificate with OpenSSL; deployed the full chain to /etc/ssl/openemr/ and enforced HTTP → HTTPS 301 redirect for offline TLS coverage.
- Hardened OS for austere field conditions: UFW firewall scoped to ports 80/22, disabled snapd and unattended-upgrades to eliminate unplanned reboots, and configured daily cron-driven encrypted backups with 30-day rotation.
- Designed HIPAA-aligned RBAC across 8 station-specific service accounts with documented post-pilot tightening plan; provisioned VirtualBox snapshot rollback strategy for rapid recovery.
- Designed and deployed a 50,000 sq ft Wi-Fi 6 mesh network spanning four buildings with segmented VLANs, DHCP/DNS, and offline-tolerant routing.
- Subsequently redesigned the system from scratch as a custom Node.js / SQLite / React application after identifying constraints OpenEMR couldn't cleanly satisfy in the field; consolidated to a single-process, systemd-managed service with hourly automated SQLite backups.
Clinical Systems & Operations
- Mapped bilingual paper-based workflow (Spanish patient-facing, English provider-facing) to OpenEMR schema across all six clinics; selected native modules where possible and scoped custom Layout-Based Forms only for gaps.
- Built Spanish-language Registration LBF (Registro de Pacientes y la Forma de Examen) mirroring 2026 paper form: demographics, vitals, allergy/medication intake, routing checkboxes, and treatment/referral sections.
- Built specialized Vision and Dental LBFs with structured medical history alerts, bilateral acuity grids, 32-tooth charting, anesthesia selection, and Rx dispensing tracking; specified autorefractor CSV ingest as next-phase integration.
- Conducted workflow discovery interviews with 8+ station leads (including providers with 26–32 mission tenure); designed paper-shadow-then-collaborative-entry training protocol that onboarded 50+ users.
- Engineered secure cloud archival pipeline via Microsoft Entra ID and SharePoint for post-mission data continuity.
Costa Rica Field Deployment (April 18–25, 2026, Grano de Oro): deployed offline LAN running the clinical platform in austere, no-internet environment supporting full-cycle traveling clinic operations. Roadmap: Laredo (Nov 4–10, 2026) LAN setup and UX skeleton test; Costa Rica (April 17–24, 2027) full incorporation; Philippines (Feb 16–25, 2027) first Asia-Pacific deployment.
Bartender · Event Operations
Apr 2023 – Apr 2025J. Martini Hospitality Group·Houston, TX·View Company
- Worked client-facing event operations across the Houston metro area: corporate gatherings, weddings, and private events for a hospitality firm specializing in premium service delivery (high-end bar service, cigar service, full-event waitstaff coordination).
- Trusted by the company owner with multi-venue supply logistics across Houston, transporting setup and inventory between sites on schedules often extending past 2 AM; supported onboarding for new event staff and on-site setup verification. Averaged ~30 hours/week over 2 years.
Founder & Operations Lead
2022 – 2024O Λ S I S·Remote · US / Ukraine / EU
- Founded and operated a competitive playtesting organization partnering with indie PvP developers to run structured pre-release events using experienced esports participants for media, feedback, and community momentum.
- Built the first competitive scene for Shatterline (Frag Lab Studio, Ukraine) from scratch near the start of the Russia-Ukraine war: negotiated dedicated practice server access across language and time-zone barriers, drafted competitive rulesets, and operated tournament brackets with grant-funded prize pools up to $600.
- Expanded to a generalized dev-partnership model after Shatterline: pitched studios at gaming conventions, nearly secured a Stockholm residency with Alara Prime before their funding collapse, and managed community transition through the bankruptcy without losing partner trust.
Technical Skills
Microsoft Azure · Entra ID · Microsoft 365 · SharePoint · IAM/RBAC · ACLs · TLS/HTTPS · least-privilege design · vulnerability management
LAN/WAN · Wi-Fi 6 mesh · DHCP/DNS · Active Directory · Linux server administration
Offline-first clinical systems · Custom EMR (Node.js · SQLite · React) · OpenEMR · OpenMRS
Python · C# · JavaScript/TypeScript · PowerShell · SQL · Git/GitHub · AWS (learning) · Splunk SIEM (home lab) · TryHackMe SOC L1
Certifications
Education
University of Central Florida
Expected Fall 2028B.S. Information Technology (CECS) · Accelerated M.S. Cyber Security & Privacy Track
Houston City College
Conferred 2025A.A.S. Artificial Intelligence · National Honor Society
GPA: 3.8
Houston City College
Conferred 2026A.S. General Science
Open to Opportunities
Open to cybersecurity, cloud & infrastructure roles