Yusniel Ruiz · Miami, FL

Senior Network & Systems Engineer.

Infrastructure that just works.

15+ years designing, securing, and automating enterprise networks and cloud identity — across 50+ client environments in healthcare, finance, legal, and education.

Microsoft 365 & Entra ID Network design & segmentation Identity security & incident response Automation · n8n, PowerShell, Python Self-hosted & virtualization Bilingual · ES/EN

01 / About

I design, secure, and automate the infrastructure organizations actually run on — networks and segmentation, Microsoft 365 identity, virtualization and backup, and the automation that keeps all of it maintainable by a small team. My clients are in healthcare, finance, legal, and education, where the systems are regulated and downtime is measured in lost revenue.

15+
years in production
50+
client environments
500+
endpoints managed
8
platforms built

02 / Skills

What I run in production.

Networking & Security

TCP/IPDNSDHCPVLANs LAN/WANVPN/IPsecNAT Wi-Fi Design & Site SurveysNetwork Segmentation SophosCiscoUbiquiti/UniFiEDR

Identity & Cloud

Microsoft 365Entra IDIntune Exchange OnlineConditional AccessAutopilot Microsoft GraphWindows ServerActive Directory Google Workspace

Infrastructure & BDR

Hyper-VProxmoxLinuxAzure Synology/NASBackup & Disaster Recovery MonitoringPatch Management

Cloud & Self-Hosted

DockerDocker ComposeVPS OllamaLocal AI InfrastructureWordPress

Automation & Tooling

PowerShellPythonREST APIs n8nGitAutotaskDatto/Kaseya RMM & PSA

Communications & Dev

Zoom PhoneZoom Contact CenterVoIP/SIP Node.jsPHP/Laravel

Leadership & Strategy

Tier 2/3 EscalationVendor & Stack Evaluation Cost OptimizationTeam LeadershipClient Consulting

03 / Experience

Fifteen-plus years, four chapters.

  1. 2024 — now

    Lead Engineer

    Empower IT Group · Miami, FL

    Managed service provider — 50+ client organizations, ~500 endpoints, 400+ users, including multi-site environments of up to six locations.

    • Senior-most technical escalation point for identity, network, security, and infrastructure across the entire client base.
    • Detected and contained multiple session token-theft intrusions, then designed the identity baseline that closed the gap and rolled it fleet-wide.
    • Owned the firewall platform decision for the client base and executed the consolidation across 20+ environments with zero business-hours downtime.
    • Migrated four clients to Zoom Phone — IVRs, queues, routing, and number porting — and cut client mailboxes over to Microsoft 365.
    • Built the automation layer the team runs on: sign-in monitoring, alert routing, and call-to-ticket workflows that recover roughly five engineer-hours a week.
    • Evaluate and select platforms through structured comparison and pilots, then rationalize licensing and cloud spend without giving up security or supportability.
    • Microsoft 365
    • Entra ID
    • Intune
    • UniFi
    • Azure
    • Proxmox
    • Zoom Phone
    • Autotask
    • n8n
    • PowerShell
  2. 2021 — 24

    Manager · Technology & Operations

    D&D Global Service LLC · Miami, FL

    50+ person operation running on manual, paper-based workflows.

    • Built and launched the company's internal sales and booking platform, replacing the manual process end to end.
    • Owned the technology stack and vendor relationships for the whole operation — selection, negotiation, and support.
    • That platform became the blueprint for the logistics system I rebuilt from scratch afterwards — same domain, second generation, everything learned from running the first one in production.
    • Laravel
    • PHP
    • MySQL
    • Vendor management
  3. 2016 — 21

    CEO & Founder

    Cumacell Technologies · Cienfuegos, Cuba

    Technology services company I founded and ran for five years.

    • Designed and managed servers, networks, and cybersecurity for 10+ business clients — the full stack, with no one else to escalate to.
    • Built a SaaS service-management platform and took it to production with paying clients on it.
    • Hired and led a six-person technical team, and owned every client relationship from first conversation to renewal.
    • Linux
    • Windows Server
    • Active Directory
    • Firewalls & VPN
    • SaaS development
  4. 2010 — 16

    Systems & Network Engineer

    Cuban Institute of Radio and Television · Cienfuegos, Cuba

    National broadcaster — multi-site infrastructure where an outage takes transmission off the air.

    • Designed, implemented, and administered servers, Active Directory, and LAN/WAN networks across sites.
    • Ran the VPN, firewall, and critical-infrastructure layer for broadcast operations that could not go down.
    • Windows Server
    • Active Directory
    • LAN/WAN
    • VPN
    • Firewalls

Education

B.S. Telecommunications & Electronics Engineering

Universidad Central "Marta Abreu" de Las Villas · Cuba · 2010

Graduated with Honors

Certifications

  • CompTIA Network+
  • CompTIA A+
  • Microsoft 365 Fundamentals (MS-900)

Vendor training

Zoom Sophos Kaseya

04 / Work

Systems that stayed up.

Two kinds of work: the platforms I designed and wrote, and the infrastructure decisions and security incidents I owned.

ABuilt

Software, automation, and self-hosted platforms I designed, wrote, and run in production.

BOwned

Platform decisions, security incidents, and network builds I owned across a 50+ client base — the calls that had to be right the first time.

INCIDENT RESPONSE & IDENTITY

Token-Theft Response & Identity Baseline

Detected and contained multiple session-token theft attempts against client tenants, then designed the identity baseline that closed the gap — and rolled it across the fleet without breaking users.

Every confirmed intrusion contained; no data loss

Engagement details

MFA stops password attacks, not token theft — the attacker doesn't need the password if they can replay the session. These arrived looking like ordinary sign-ins: valid token, correct MFA state, wrong everything else. Containing them is incident work; making sure the next one fails is design work. I did both, and the second half is what actually mattered.

  • Detection from sign-in telemetry rather than an alert someone else wrote — impossible travel and anomalous token use surfaced through automated monitoring I built.
  • Containment on the clock: sessions revoked, credentials and app secrets rotated, persistence checked for (mail rules, app consents, device registrations), and the full sign-in trail reconstructed to bound the exposure.
  • Root cause turned into policy — Conditional Access covering device state, sign-in risk, and admin elevation, staged in report-only mode first so the rollout never blocked a working user.
  • Baseline standardized so every tenant lands in the same known-good state: legacy authentication off, break-glass accounts established and correctly excluded, device compliance gating access.
  • Kept current as Microsoft moves defaults underneath — the baseline is maintained, not delivered once.

Platforms

  • Entra ID
  • Conditional Access
  • Identity Protection
  • Intune
  • Defender for Office 365
  • Microsoft Graph
PLATFORM STRATEGY

Fleet-Wide Firewall Consolidation

Owned the decision to move the client base onto a single firewall platform, ran the vendor evaluation behind it, and executed the migrations and hardware refresh across 20+ environments.

One platform, one policy baseline, lower recurring spend

Engagement details

A fleet of one-off firewalls is a fleet nobody can reason about. Every incident starts by learning that site's particular setup, every renewal is its own negotiation, and no two rule sets mean the same thing. The technical work here was the easy half — the real call was choosing what the whole client base would standardize on and defending that choice against the cost of switching.

  • Structured vendor evaluation — capability, licensing model, support path, and total cost over the refresh cycle, not a feature checklist.
  • Four clients migrated off Sophos to UniFi with rule sets rebuilt against a common template rather than translated one-to-one, so the result is a baseline instead of 20 dialects.
  • Hardware refreshed across the client base, retiring devices past end-of-support before they became someone's outage.
  • Every cutover scheduled off-hours with a tested rollback — no business-hours downtime across the program.
  • Recurring licensing spend reduced while keeping the security posture and the support path intact.

Platforms

  • UniFi Security Gateway
  • Sophos
  • Site-to-site VPN
  • VLAN segmentation
  • Vendor evaluation
NETWORK DESIGN

Campus Wireless & VLAN Segmentation

Designed a 300+ user campus wireless network from RF survey to AP placement, and the segmented guest/student/VoIP/corporate VLAN architecture underneath it — cut over live, without downtime.

Full campus redesign, zero downtime

Engagement details

300+ users where guest devices, student devices, phones, and staff workstations all shared one flat network — so any compromised laptop had a clear path to everything, and nobody could tell which of the four was saturating the wireless. The constraint that shaped the whole design: the campus could not go offline for it, so the new architecture had to be built alongside the old and traffic moved across in stages.

  • Physical site survey and AP placement driven by measured signal and client density, not floor-plan guesswork.
  • Guest, student, VoIP, and corporate traffic split onto separate VLANs, with inter-VLAN routing restricted to what each segment genuinely needs.
  • VoIP prioritized with QoS so call quality holds under full classroom load.
  • Guest network isolated from every internal resource by default rather than by exception.
  • Staged migration executed with zero campus downtime.

Platforms

  • Ubiquiti UniFi
  • 802.1Q VLANs
  • RF site survey
  • QoS
  • Inter-VLAN routing
CLOUD ADMINISTRATION

CIPP Self-Hosted on Azure/Linux

Moved the multi-tenant management console — the system holding delegated access to every client tenant — off a hosted instance and onto Linux in our own Azure subscription.

Delegated access to every tenant, held in-house

Engagement details

CIPP is the console every client tenant is managed through, which makes it the highest-value target we run: whoever holds it holds delegated administrative access to all of them. A hosted instance means someone else holds that. Self-hosting is more work and it is the correct trade — the credentials, the audit trail, and the upgrade schedule are ours.

  • Deployed and migrated CIPP to Linux on Azure without losing tenant connections or re-consenting every client.
  • App registration scoped to only the permissions actually used, rather than the permissive default set.
  • Administrative access locked behind identity controls, with the audit trail retained in infrastructure we control.
  • Backup and restore path defined and tested, so a bad upgrade is a recovery instead of a rebuild.
  • Maintained through upstream releases — updates staged and validated rather than applied blind to a system with that blast radius.

Platforms

  • Microsoft Azure
  • Linux
  • CIPP
  • Entra app registrations
  • Microsoft Graph
Self-hosted console across 25 tenants, 522 users, 401 mailboxes
Self-hosted console across 25 tenants, 522 users, 401 mailboxes

05 / Contact

Let's talk about what you're running.

yusniel@theruiz.net
Miami Springs, FL
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