Open to remote senior/staff roles and contracts

Gabe Fernandez

Principal Software Engineer · Full-Stack, Mobile & Applied AI

I take products from idea to production: AI voice agents, full-stack web platforms, and native iOS apps.

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About

Building products that matter

I'm a product-minded engineer with 20+ years of experience building and running production software. Today I'm co-founder and CTO of Receptiva, a bilingual AI phone receptionist for law firms, and I lead engineering on contract for an orthopedic second-opinion medical platform.

Before that I spent 13 years at USAA, most recently as tech lead and solution architect for the Join USAA eligibility platform. I run an AI-native engineering practice built on agentic coding tools, evals, and human-reviewed automation, and I'm named inventor on 70 granted U.S. patents.

Portfolio

Featured Projects

Real projects with real outcomes. From AI voice agents to full-stack web platforms and native iOS apps.

Receptiva
Active

Receptiva

Co-Founder & CTO

Bilingual AI phone receptionist for personal-injury law firms. Answers, triages, and routes every inbound call in English and Spanish.

  • Real-time voice agent with a swappable model layer and warm transfer to attorneys over SIP
  • Eval service that regression-tests call behavior before each deploy
  • Self-serve onboarding that provisions phone numbers, plus Stripe subscriptions
  • Public REST API and MCP server with OAuth 2.1 so firms can use Receptiva from Claude and ChatGPT
Realtime Voice AIPythonNext.jsTypeScriptPostgreSQLStripe
Orthopedic Second-Opinion Platform
Active

Orthopedic Second-Opinion Platform

Lead Software Engineer (Contract)

Medical platform that gives professional athletes orthopedic second opinions, with medical imaging, physician reports, and payments.

  • Resolved the critical bugs and deployment issues blocking launch
  • Security and privacy release: closed privilege-escalation and record-takeover paths, locked down athlete records and images
  • Infrastructure as code with Terraform: every change previewed as a plan on its pull request, then deployed automatically through CI/CD
AWSTerraformDICOMTypeScript
BookMatcher
Active

BookMatcher

Founder & Full-Stack Engineer

AI-powered book recommendations and reading tracker, on iOS and the web.

  • iOS app live on the App Store (SwiftUI, Swift 6 strict concurrency, Clean Architecture)
  • AI recommendations from a reader's taste profile and favorite books
  • Next.js web app with programmatic SEO and a TypeScript Hono API on Vercel
SwiftUINext.jsTypeScriptHono
Recall Beacon
Active

Recall Beacon

Founder & Lead Engineer

Product-safety recall alerts for families: food, medicine, products, and vehicles.

  • Recalls aggregated from FDA, USDA, CPSC, and NHTSA in one feed
  • Push alerts when products you care about are recalled
  • Firebase Functions (Node/TypeScript) ingest pipeline
SwiftUIFirebaseTypeScriptRevenueCat
AOTL Septic Service
Completed

AOTL Septic Service

Lead Full-Stack Engineer

Field and back-office app for a septic service company, streamlining field operations, customer management, and service report generation.

  • Automated service report generation
  • Customer search and management
  • Back-office management and reporting
ReactNext.jsTypeScriptNode.js

Other Work

SoTexFund
Completed

SoTexFund

General Partner & Lead Developer

Marketing website for a real estate investment fund focused on distressed assets in San Antonio and South Texas.

Next.jsReactTypeScriptTailwind CSS
Schertz RV Park
Completed

Schertz RV Park

Lead Developer

Marketing website for a family-friendly RV park near San Antonio, featuring amenities, pricing, and contact information.

Next.jsReactTypeScriptTailwind CSS
Tax Delinquent Tracker
In Development

Tax Delinquent Tracker

Lead Full-Stack Engineer

Web app for tracking and analyzing tax-delinquent properties from Texas county tax sales with automated data enrichment.

Next.jsTypeScriptDrizzle ORMNeon PostgreSQL

Experience

Work History

A track record of delivering impactful software at scale.

Jan 2026 — Present

Co-Founder & CTO

ReceptivaRemote
  • Co-founded and built a bilingual (English/Spanish) AI phone receptionist for personal-injury law firms; live in production since June 2026, answering, triaging, and routing inbound calls
  • Built the real-time voice agent in Python with a swappable model layer, so each firm runs on the voice model that fits its calls; warm transfer to attorneys over SIP; and an eval service that regression-tests call behavior before each deploy
  • Built the Next.js / TypeScript platform: self-serve setup that provisions phone numbers, firm dashboard, Stripe subscriptions, and a durable post-call pipeline that extracts structured leads into Postgres
  • Designed a public REST API and MCP server with OAuth 2.1 + PKCE so firms can use Receptiva from Claude and ChatGPT; deny-all row-level security, cross-tenant isolation tests, and an append-only audit log
PythonRealtime Voice AILLM EvalsTypeScriptNext.jsHonoPostgreSQLStripeMCPOAuth 2.1SentryPostHogVercel
2026 — Present

Lead Software Engineer (Contract)

Orthopedic Medical Platform (Confidential Client)Remote
  • Own engineering for an AWS-hosted orthopedic second-opinion platform used by professional sports teams, handling athletes' medical imaging (DICOM), physician reports, and payments
  • Resolved the critical bugs and deployment issues blocking launch; run the product roadmap with the founders
  • Led a security and privacy release: closed privilege-escalation and record-takeover paths, blocked unauthenticated access to athlete records, and added server-side access checks on images
  • Rebuilt delivery with Terraform plans previewed on every pull request, automated deploys, and a single image-upload pipeline with failure alerts
AWSTerraformDICOMCI/CDSecurity
Apr 2025 — Present

Founder & Principal Engineer

CodeHarmonic, LLCRemote
  • BookMatcher: AI book recommendations and reading tracker. iOS app on the App Store (SwiftUI, Swift 6), Next.js web app with programmatic SEO, and a TypeScript Hono API on Vercel with Supabase and Inngest
  • Recall Beacon: product-safety recall alerts aggregated from FDA, USDA, CPSC, and NHTSA. SwiftUI iOS app with RevenueCat subscriptions and Firebase Functions ingest and push notifications
  • Built an agentic "software factory": scheduled Claude Code loops that triage Sentry alerts, pick up Linear issues, write a failing test first, and open draft PRs, all behind hooks and a written risk policy so a human reviews and merges
  • Client work: field and back-office operations app for a septic service company that automates technician service reports
SwiftSwiftUITypeScriptNext.jsHonoSupabaseFirebaseInngestRevenueCatOpenAIClaude CodeVercel
Dec 2021 — Apr 2025

Lead Software Engineer

USAASan Antonio, TX
  • Tech lead and solution architect for the Join USAA eligibility platform: React front end and Java / Spring Boot microservices handling 1M+ requests a day
  • Led the rollout of SLOs and SRE practices across services, ran the 24/7 on-call rotation for critical systems, and set code-review standards for the team
  • Program tech lead across teams; mentored junior engineers and interns
  • Shipped full-stack features on usaa.com/join with React, Redux, Java, Spring, Kafka event pipelines, Cypress, and CI/CD
JavaSpringReactReduxRESTOAuthJWTKafkaSQLDockerCI/CDGitLabPrometheusGrafanaSREDataDogCypress
Jul 2017 — Dec 2021

Senior Software Engineer

USAASan Antonio, TX
  • Developed back-end APIs on modern infrastructure using OpenShift, Docker, JBoss, Spring, REST, CyberArk, JWT, GitLab CI/CD
  • Worked with specialty testing teams on defect resolution, root cause analysis, addressing security and performance findings
  • Collaborated with IT architecture and business teams to design complex technical solutions and influence requirements
  • Served as Pulse Champ, provided mentorship and coaching to junior developers
JavaSpringHibernateReactReduxRESTJBossOpenShiftDockerCI/CDGitLabPrometheusGrafanaELK
Jan 2012 — Jun 2017

Research Engineer (IT Security / Fraud)

USAASan Antonio, TX
  • Led development of Adaptive DDoS Mitigation library for USAA iOS Mobile App (patent granted), coordinating with Akamai team
  • Led Cybersecurity research team of FTEs and contractors; evaluated vendor ML technologies and conducted executive innovation briefs
  • Developed driver license and selfie capture technology on iOS using Machine Learning Vision APIs
  • Designed and executed Production Pilot of Behavioral Profiling technology on USAA.com infrastructure
  • Evaluated Intel IPT for Member Desktop QuickLogon and Employee VPN Logon
SwiftObjective-CiOSAndroidJavaMachine LearningAWSAkamaiF5WebSphereCybersecurityFraud Prevention
May 2010 — Dec 2011

Graduate Assistant, ELITE Graduate Program

Texas A&M University-Corpus ChristiCorpus Christi, TX
  • Developed web-based application for intake, registration, and tracking of graduate students within grant-funded program
  • Coordinated Web 2.0 technologies, produced workshop videos, enhanced integrations between website and social media
  • Managed IT and departmental web site, implemented e-mail marketing system, developed customized reporting and analytics
PHPMySQLHTMLCSSJavaScriptWordPressApacheLinuxAnalyticsAdobe Creative Suite
Jan 2008 — May 2010

Web Design & IT Services

ContractingTexas
  • Designed and developed web sites for small businesses including Albermarle-Texas.com and ElectricTanCC.com
  • Unisys Technical Services Helpdesk Technician: provided IT troubleshooting and support for Government employees
HTMLCSSJavaScriptPHPMySQLApacheLinuxWordPressJoomlaDrupal
Jun 2003 — Jan 2008

President / CEO

TimeLock Enterprise, LLCTexas
  • Founded internet marketing and e-commerce startup; created, developed, and maintained WatchKings.com
  • Established supplier relationships, implemented PPC campaigns and SEO strategies achieving top five rankings
HTMLCSSJavaScriptPHPMySQLApacheLinuxE-CommerceSEOPPC

Education

Academic Background

Master of Science in Computer Science

University of Texas at San Antonio

San Antonio, TXMay 2019

Concentration: Cybersecurity

Deep Learning Approaches for Network Intrusion Detection

Laboratory for Cybersecurity Dynamics (LCD)

Bachelor of Science in Construction Science

Texas A&M University

College Station, TXDecember 2007

Credentials

Professional Development

Continuous learning across AI, machine learning, and cybersecurity.

AI & Tools

Claude Code in Action

Anthropic - Oct 2025

Machine Learning

Convolutional Neural Networks

Coursera (deeplearning.ai) - Dec 2017

Structuring Machine Learning Projects

Coursera (deeplearning.ai) - Oct 2017

Improving Deep Neural Networks

Coursera (deeplearning.ai) - Sep 2017

Neural Networks and Deep Learning

Coursera (deeplearning.ai) - Sep 2017

Cybersecurity

Cybersecurity: Technology, Application and Policy

MIT CSAIL - Spring 2016

Software Defined Radio and Digital Signal Processing

BlackHat - Aug 2014

Designing Secure Protocols and Intercepting Secure Communication

BlackHat - Aug 2013

Innovation

Innovator Certification

UT Austin IC2 Institute - Fall 2014

Expertise

Skills & Technologies

20+ years across applied AI, backend, web, and mobile development.

Applied AI

Core Expertise
Realtime Voice AgentsSpeech-to-Speech ModelsLLM APIsMCP ServersLLM EvalsClaude CodeAgentic WorkflowsPrompt Engineering

Mobile

Core Expertise
SwiftSwiftUIUIKitObjective-CCore DataSwift ConcurrencyCombineasync/await

Backend

Core Expertise
Node.jsTypeScriptPythonJavaSpring BootHonoDurable WorkflowsExpressGraphQLREST APIsKafkaMicroservicesSecure Coding

Web

Core Expertise
Next.jsReactTypeScriptJavaScriptTailwind CSSVercel

Data & Cloud

PostgreSQLFirebaseNeonMongoDBRedisAWSGCP

DevOps & Quality

GitCI/CDDockerTerraformKubernetesSentryPostHogGitHub Actions

Contact

Let's Work Together

Have a project in mind? Let's discuss how I can help you build something great.

Get In Touch

I'm currently available for contract work and interesting projects. If you need help building production-quality apps, feel free to reach out.