Alexander Ahern - Software Engineer
Senior / Staff Full Stack Engineer
Web · Mobile · Cloud · AI
11 Years Experience · Full Stack · Mobile · AI
Senior/Staff Full Stack Engineer with 11 years of experience building and operating production software across web, mobile, distributed systems, cloud, and AI-enabled applications. Deep experience with React, TypeScript, Node.js, React Native, PostgreSQL, AWS, APIs, and modern application architecture.
Senior / Staff Full Stack Engineer · Web · Mobile · Cloud · AI
Senior/Staff Full Stack Engineer with 11 years of experience building and operating production software across web, mobile, distributed systems, cloud, and AI-enabled applications. Deep experience with React, TypeScript, Node.js, React Native, PostgreSQL, AWS, APIs, and modern application architecture.
Build. Ship. Scale.
About Me
OVERVIEW
Senior/Staff-level full-stack engineer with 11 years of experience designing, building, modernizing, and operating production software across logistics, commerce, construction, enterprise systems, and SaaS.
ENGINEERING
Experienced across the full software lifecycle, from architecture, data modeling, APIs, and frontend systems through testing, CI/CD, observability, performance optimization, incident response, and production operations.
AI & PLATFORM
Expanded this foundation into AI-enabled application architecture, including RAG, vector search, LLM routing, agent infrastructure, workflow automation, and containerized platform engineering.
Tech Stack
Production-focused stack spanning full-stack web and mobile development, distributed systems, cloud infrastructure, data platforms, testing, observability, and AI-enabled applications.
AI & Automation
RAG
LangChain
Ollama
OpenRouter
LiteLLM
MCP Servers
AI Agents
n8n
Whisper.cppFrontend & Mobile
React
Next.jsReact Native
Vue
Angular
TypeScript
JavaScript
Storybook
Remix
GatsbyBackend & APIs / Cloud
Node.js
Express
NestJS
FastAPI
Python
Spring Boot
Django
Flask
Laravel
Ruby on Rails
REST APIs
GraphQL
AWSState, Data & Infrastructure
PostgreSQL
pgvector
MySQL
DynamoDB
MongoDB
Redis
Qdrant
Docker
Kubernetes
TerraformTesting, Delivery & Observability
Playwright
Cypress
GitHub Actions
Sentry
Datadog
Grafana
Prometheus
CloudWatchExperience
11 years building, modernizing, and operating production systems across logistics, commerce, construction, enterprise platforms, SaaS, mobile, cloud, and AI-enabled applications.
Senior Full Stack & AI Engineer • Independent Consultant (Contractors)
Sep 2024 — Present- Lead architecture and delivery for web, mobile, SaaS, platform, and AI-enabled engagements spanning greenfield development, modernization, performance optimization, and legacy-system recovery.
- Architected a B2B logistics platform using React, Node.js, PostgreSQL, and AWS processing approximately 40,000 shipment events per day.
- Rebuilt a Shopify storefront for a merchant generating approximately $2M annually, reducing mobile checkout load time from 6.2 seconds to 1.4 seconds; the client reported a 17% increase in completed checkouts the following quarter.
- Designed and shipped an offline-first React Native field-inspection application to iOS and Android within nine weeks.
- Architect and operate containerized infrastructure spanning 20+ services and built semantic retrieval using PostgreSQL/pgvector, Qdrant, LiteLLM, Ollama, OpenRouter, and MCP servers.
Staff Software Engineer, Mobile • Procore Technologies
Jan 2023 — Aug 2024- Built and evolved React Native applications supporting construction professionals across production iOS and Android environments.
- Designed offline-first synchronization architecture incorporating conflict resolution, persistent queues, retries, and resilient photo uploads for unreliable field connectivity.
- Owned mobile release quality, production crash analysis, observability, and incident triage using Sentry.
Senior Developer, Storefronts • Shopify
Nov 2021 — Dec 2022- Worked on high-scale commerce and storefront systems with direct responsibility for rendering performance and Core Web Vitals.
- Diagnosed and resolved storefront and checkout performance bottlenecks through JavaScript bundle optimization, image-pipeline improvements, third-party script analysis, and edge caching.
- Developed across Shopify's large-scale Ruby ecosystem alongside modern JavaScript storefront architectures.
Senior Software Engineer • Flexport
Jul 2019 — Oct 2021- Built logistics applications supporting shipment visibility, freight operations, and dispatcher workflows using React, TypeScript, Node.js, PostgreSQL, and GraphQL.
- Developed high-volume shipment-event pipelines powering customer tracking experiences and internal operational tooling.
- Led the rewrite of a customer-facing shipment tracking application and established the team’s first substantial automated testing strategy.
Senior Software Engineer • Work & Co
Mar 2017 — Jun 2019- Delivered production software across four-to-six-month client engagements spanning frontend, backend, commerce, CMS, and infrastructure concerns.
- Built applications across React and Vue ecosystems and inherited and stabilized Angular applications.
- Delivered WordPress and Drupal migrations and a Magento-to-Shopify replatform, including checkout redevelopment.
Software Development Engineer I • Amazon
Aug 2015 — Feb 2017- Developed backend services for Amazon Fulfillment Technologies supporting operationally critical inventory-reconciliation workflows.
- Built production services using Java, Spring, DynamoDB, and AWS.
- Joined production on-call within four months and diagnosed operational incidents through CloudWatch and Splunk.
Education
Carnegie Mellon University
Bachelor of Science, Computer Science
2011 - 2015- Bachelor of Science in Computer Science
Projects
A selection of software projects showcasing my technical skills and problem-solving abilities.
Hobbies
A look at my life outside of work.