Resume

A little more about me

> CONTACT

Andrew Croskery - Software Engineer

Ottawa, ON, Canada | 613.668.5138 | acroskery@gmail.com | linkedin.com/in/acroskery | github.com/croskery

> README

Driven Software Engineer with 10+ years building scalable systems in startup and enterprise environments. Specialized in backend development, microservice architectures, and embedded Linux systems. Strong technical leader with proven ability to architect solutions from scratch, mentor teams, and deliver in high-pressure situations. Seeking opportunities to tackle complex technical challenges and expand expertise.

> TECH_STACK

Languages
Python, Elixir, Kotlin, C/C++, SQL, Java, HTML/CSS
Backend Frameworks
Django, Phoenix LiveView, Spring Boot, GraphQL (Graphene, DGS), Ecto, JOOQ, Oban
Cloud & Infrastructure
AWS (ECS, RDS, S3, Lambda, IAM), Terraform, Docker, GitHub Actions, Jenkins
Databases & Storage
PostgreSQL, SQL optimization, Flyway, Redis
Monitoring & Observability
Datadog, AppSignal, Sentry, APM, custom metrics
APIs & Protocols
REST, GraphQL, SNMP, YANG, Shopify API
Development Practices
Test-Driven Development, Domain-Driven Design, Continuous Integration/Deployment, Infrastructure as Code

> WORK_HISTORY

ReturnBear Tech Lead / Senior Backend Engineer
December 2022 - Present (~3 years) | Remote
Pre-Series A Startup | Reverse Logistics Platform | Engineering team <25
  • Lead team of 4 engineers while maintaining 80%+ hands-on development, adding technical mentorship and hiring responsibilities to existing individual contributor role
  • Architected and built end-to-end reverse logistics platform integrating Shopify order management, multi-carrier shipping via ShipEngine, and warehouse operations across 5 international hubs (North America, UK, Australia) serving 50+ merchants processing hundreds of items daily
  • Leading zero-downtime migration from Django/React to Phoenix LiveView/Elixir architecture, gradually migrating components while maintaining production service for live merchants
  • Implemented intelligent routing system optimizing shipment costs and domestic preference, with merchant-specific rules for directing products to designated hubs based on SKU and warehouse capabilities
  • Built 0-to-1 hub processing application in Django/Python, replacing manual Retool-based workflows and enabling warehouse teams to scan, assess, repackage, and process returned inventory at scale
  • Designed PostgreSQL data models for complex reverse logistics workflows including return case management, multi-warehouse inventory tracking, routing rules, and merchant fulfillment reconciliation
  • Developed GraphQL APIs using Graphene for real-time warehouse operations, enabling staff to scan items, update condition assessments, and trigger fulfillment workflows
  • Provisioned and managed AWS infrastructure using Terraform including ECS services, RDS PostgreSQL databases, and S3 storage across dev/staging/prod environments, establishing infrastructure-as-code practices
  • Led cross-functional team of 5 engineers during platform scaling from initial pilot to production deployment across multiple warehouse locations
Elemy Senior Backend Engineer
September 2021 - December 2022 | Remote
Series A Startup | Healthcare Platform | ~1,000 employees, Engineering <50
  • Designed and implemented row-level authorization using PostgreSQL views and Hasura rules to enforce HIPAA-compliant data access controls, restricting therapist and patient medical records based on care relationships across 1,000+ providers
  • Architected marketplace data models in PostgreSQL managed via Flyway, enabling therapist-patient matching for 1,000+ therapists and patients, including provider qualifications, treatment specializations, and multi-state operations
  • Built GraphQL APIs in Kotlin/Spring Boot using Netflix DGS for patient onboarding workflows, implementing multi-step application process with eligibility screening to identify ideal care candidates
  • Developed daily ETL pipeline extracting thousands of clinical notes from legacy Catalyst system into structured PostgreSQL records, enabling parents to access therapist documentation and treatment progress
  • Enhanced Datadog observability by implementing structured logging using Java MDC for request tracing and integrating PagerDuty alerting, enabling on-call engineers to respond rapidly to production healthcare service incidents
Ciena Microservice Framework Engineer / Photonic OAM Engineer / Photonic Control Engineer
2012 - September 2021 (9 years) | Ottawa, ON, Canada
Public Telecommunications Company
  • Co-developed embedded microservice framework in C/Python for Linux-based optical networking systems, replacing aging VxWorks monolith and enabling service reusability across photonic control applications deployed to global telecom infrastructure
  • Built "Deployment Launcher" enabling data-driven microservice orchestration via XML/JSON configuration, eliminating code changes for service deployment and automatically configuring framework components (messaging, database, IPC)
  • Implemented automated memory leak detection in test framework promoting functional programming patterns and preventing production memory issues in embedded systems running continuously in carrier networks
  • Architected template-driven YANG-SNMP translation microservice enabling zero-code integration of new photonic circuit packs through data-driven mapping files, reducing circuit pack onboarding from several weeks to days and eliminating regression testing overhead
  • Designed event-driven power monitoring system using statistical deadzoning to trigger photonic control algorithms only on significant power fluctuations, reducing CPU overhead and enabling sleep states in embedded shelf processors
  • Mentored engineering team during monolithic-to-microservice architecture migration, establishing patterns and best practices for decomposing legacy VxWorks codebase into reusable services
  • Developed "Data Collector" service polling real-time power measurements from photonic circuit packs via SNMP, scaling and distributing telemetry to control algorithms managing optical signal transmission across terrestrial and submarine networks
  • Designed and implemented photonic control algorithms, dynamically adjusting individual channel power levels to prevent interference and compensate for amplifier tilt across long-haul fiber spans
  • Provided root cause analysis and emergency fixes for critical production outages affecting major carrier and enterprise customers, working directly with support teams to restore service and prevent recurrence
  • Mentored new hires and co-op students on embedded systems development, SNMP protocols, and optical networking fundamentals over 6-year tenure

> EDUCATION

University of Ottawa BASc - Computer Engineering
magna cum laude | 2007 - 2011 | Ottawa, ON, Canada

> ACHIEVEMENTS

U.S. Patent 10,797,818 | "Dynamic Data-Driven Power Scaling in an Optical Node and Network" | 2020