Mario Galeno
Work History

Experience

Over a decade of shipping production software at companies ranging from early-stage startups to Amazon Web Services. I thrive in complex, high-stakes domains where quality and reliability matter.

Senior Software Engineer

Hims & Hers

Remote

2024 – Present
  • Integrated deep-link CTA handling and GraphQL data into a post-purchase treatment tracking feature in React Native, surfacing order status for users.
  • Delivered full-stack features independently — from React Native and Next.js on the client, GraphQL BFF and NestJS in the middleware layer, and Kotlin/Spring Boot backend services — decoupling frontend and backend dependencies on tight deadlines.
  • Reduced integration friction on the greenfield Insights feature by establishing a pattern where mobile owned GraphQL query wiring and abstracting dense business logic into a dedicated utility layer — resulting in smaller PRs and reduced end-to-end integration issues.
  • Built GrowthBook experiments across multiple flows — Insights, cancellation, reactivation, and alternative product offerings — to drive data-informed decisions.
  • Partnered with product to instrument Amplitude events and build dashboards that gave the team visibility into real user engagement patterns.
  • Built milestone patient check-ins across mental health, weight loss, hair, and hormone health programs — ensuring they surfaced at the right moment across action item sidebars and subscription banners on mobile and web.
  • Led mobile and GraphQL planning for a follow-up labs feature — owning scoping, estimation, and query design while coordinating requirements with CRM and EMR stakeholders.
TypeScriptKotlinNext.jsReact NativeGraphQLNestJSSpring BootGitHub ActionsNx MonorepoGrowthBookAmplitudeJestStripeDatadog

Software Development Engineer

Amazon Web Services

Remote

Oct 2022 – 2024
  • Eliminated manual infrastructure overhead by migrating internal frontend consoles from a legacy hosting tool — requiring management of routing, VPN configurations, and certificate renewals — to fully managed deployment environments.
  • Upgraded IoT MQTT client from MQTT3 to MQTT5, improving connection reliability and expanding the control users have over connection behavior.
  • Extended IoT Core settings to support custom certificate signing and TLS 1.3 protocol, enhancing security and flexibility for enterprise customers.
  • Consolidated CI/CD pipelines across 9 supported packages into shared packages with consistent checks and rollback handling, replacing fragmented legacy pipelines that lacked basic reliability guarantees.
TypeScriptReactAWSCI/CDAndroid

Software Engineer → Senior Software Engineer

Tempus Labs

Chicago, IL

May 2020 – Oct 2022
  • Built a mobile UI surfacing DNA and tumor analysis results for oncology providers, improving how clinicians access and act on diagnostic data.
  • Resolved critical discrepancies between mobile app and PDF report values by implementing a version module system that alerted on unexpected or unsupported report versions — leading to a company-wide report standardization initiative for safer, more consistent output.
  • Drove adoption of TDD and modern React Native best practices, and collaborated with product and design to scope quarterly roadmaps.
  • Built mobile development frameworks and plug-and-play integration systems, enabling non-mobile engineers to ship services without mobile expertise.
TypeScriptReact NativeGitHub ActionsSwift / iOS

Senior Technical Consultant

Kin + Carta

Chicago, IL

May 2017 – Apr 2020
  • Led a team of engineers to redesign a healthcare insurance client's customer portal, improving UX while meeting WCAG 2.1 and ADA accessibility compliance requirements.
  • Built a sandbox API that bridged the gap between backend contracts and frontend development, improving collaboration across teams.
  • Developed an internal employee rewards platform in Angular backed by an Ethereum smart contract, allowing staff to reward each other and redeem company swag.
  • Led the migration of a Fortune 500 fintech client's mobile application from native iOS to React Native, optimizing performance and modernizing the codebase.
  • Maintained and extended native iOS SDK features including Face ID, Touch ID, and Core Location within existing client applications.
  • Built Spring Boot REST APIs for internal tooling and contributed to CI/CD pipeline automation for Java backend services.
  • Mentored developers across client engagements through structured code reviews, pair programming, and knowledge transfers.
TypeScriptSwiftJavaReactReact NativeAngularSpring BootCI/CDSwift / iOS

Full Stack Developer

HaloPays

Grand Rapids, MI

Nov 2014 – May 2017
  • Developed and maintained the BlueFire charitable donation web application, building merchant and reporting features on a PHP/LAMP stack.
  • Designed and built the HaloPays payment gateway API, supporting third-party payment providers and external developers building integrations against the platform.
  • Hosted and operated applications on AWS using EC2, ELB, Route 53, and S3.
  • Self-taught iOS development to research, design, and implement the BlueFire mobile application in Swift from scratch.
  • Defined technical integration requirements for payment vendor partnerships and acted as the primary technical contact for white-label clients, translating business needs into actionable API contracts.
SwiftPHPMySQLAWSSwift / iOS

Education

Academic Background

Bachelor of Science, Computer Science

Grand Valley State University

2010 – 2014

Certifications

Professional Certifications

Associate Cloud Engineer

Google Cloud Platform

Certified

Interested in working together?

I'm actively looking for my next opportunity. Let's talk.

Get in touchEmail me

Mario Galeno

Software Engineer

Holland, MI  ·  [email protected]  ·  (616) 566-0103  ·   linkedin.com/in/mario-galeno

Experience
Senior Software Engineer2024 – Present

Hims & Hers  ·  Remote

  • Integrated GraphQL data and deep-link CTAs into a React Native post-purchase treatment tracking feature.
  • Delivered features end-to-end across React Native, Next.js, GraphQL BFF, NestJS, and Kotlin/Spring Boot independently.
  • Reduced Insights feature integration friction by standardizing GraphQL query ownership and abstracting business logic into a dedicated utility layer.
  • Built GrowthBook experiments across Insights, cancellation, reactivation, and alternative product flows.
  • Instrumented Amplitude events and built dashboards to measure feature adoption across mobile and web.
  • Built milestone patient check-ins for mental health, weight loss, hair, and hormone health — surfaced via action item sidebars and subscription banners.
  • Led mobile and GraphQL planning for a follow-up labs feature, coordinating with CRM and EMR stakeholders.
TypeScriptKotlinNext.jsReact NativeGraphQLNestJSSpring BootGitHub ActionsNx MonorepoGrowthBookAmplitudeJestStripeDatadog
Software Development EngineerOct 2022 – 2024

Amazon Web Services  ·  Remote

  • Migrated internal frontend consoles to fully managed environments, eliminating manual routing, VPN, and certificate overhead.
  • Upgraded IoT MQTT client from MQTT3 to MQTT5, enabling reconnection handling and configurable connection lifecycle control.
  • Extended IoT Core to support custom certificate signing and TLS 1.3 for enterprise customers.
  • Consolidated CI/CD pipelines across 9 packages into shared packages with consistent checks and rollback handling.
TypeScriptReactAWSCI/CDAndroid
Software Engineer → Senior Software EngineerMay 2020 – Oct 2022

Tempus Labs  ·  Chicago, IL

  • Built a mobile UI surfacing DNA and tumor analysis results for oncology providers.
  • Implemented a version module system to resolve mobile/PDF report discrepancies, spurring a company-wide report standardization initiative.
  • Championed TDD and React Native best practices; collaborated with product and design to scope quarterly roadmaps.
  • Built mobile frameworks and plug-and-play integration systems enabling non-mobile engineers to ship features independently.
TypeScriptReact NativeGitHub ActionsSwift / iOS
Senior Technical ConsultantMay 2017 – Apr 2020

Kin + Carta  ·  Chicago, IL

  • Led redesign of a healthcare insurance client portal meeting WCAG 2.1 and ADA accessibility requirements.
  • Built a sandbox API bridging backend contracts and frontend development, improving cross-team collaboration.
  • Developed an Angular employee rewards platform backed by an Ethereum smart contract.
  • Led iOS-to-React Native migration for a Fortune 500 fintech client's mobile application.
  • Extended native iOS SDK features including Face ID, Touch ID, and Core Location.
  • Built Spring Boot REST APIs and contributed to CI/CD automation for Java backend services.
  • Mentored developers through code reviews, pair programming, and knowledge transfers across client engagements.
TypeScriptSwiftJavaReactReact NativeAngularSpring BootCI/CDSwift / iOS
Full Stack DeveloperNov 2014 – May 2017

HaloPays  ·  Grand Rapids, MI

  • Built and maintained the BlueFire charitable donation web app with merchant and reporting features on a PHP/LAMP stack.
  • Designed and built the HaloPays payment gateway API for third-party provider integrations.
  • Deployed and operated production infrastructure on AWS (EC2, ELB, Route 53, S3).
  • Self-taught iOS development and built the BlueFire mobile application in Swift from scratch.
  • Defined technical requirements for payment vendors and served as technical liaison for white-label clients.
SwiftPHPMySQLAWSSwift / iOS
Education
Grand Valley State University2010 – 2014

Bachelor of Science, Computer Science

Certifications
Associate Cloud EngineerGoogle Cloud Platform