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Alex Riedler

Senior Software Developer

Toronto, Canada

About

Hi I'm Alex, a UW Computer Science graduate with interest in distributed systems, data-stores, and software architecture. I care about not only delivering features but how they perform in production and meet customer expectations. By focusing on both metrics and user feedback, I believe we can together build a better web and society.

Download my CV

Experience

Senior Software Developer

Influitive Inc
July 2017 - Feb 2018
  • Worked on Hanami (Ruby) based micro-services for chat and discussions
  • Performance optimization of Sidekiq jobs over 30 percent improvements of overall job throughput using same hardware
  • Postgres Lock contention investigation and cleanup
  • Involved in architecture discussions around event based systems

Senior Software Developer - Infrastructure

VarageSale
Sept 2014 - June 2017
  • Rebuild Notifications System as a service (serves over 10 million notifications a day)
  • Avatar Service written in Elixir to support both Facebook and Custom User Avatars (High Throughput, over 70K RPM per box)
  • Analytics Integration with Third Parties (MixPanel, Amplitude, Google, Segment) on Front-end and Back-end
  • Analytics pipeline for user events and attribution analysis using Kafka, Secor, Google DataFlow, Google BigQuery
  • Diagnose various performance bottlenecks: MySQL indices missing, long running transactions, deadlocks, Redis contention

Senior Software Developer - Devops

VarageSale
Sept 2014 - June 2017
  • N+1 Queries, Fetch Patterns, Caching (Memcached + Memory), Repeated Queries, Unnecessary Queries, Lock Contention
  • Improve ElasticSearch Index for improved search and scalability (over 40% CPU reduction; resulting in less machines)
  • Write Ansible Playbooks for provisioning production systems
  • Dockerize Ruby on Rails monolith for local development
  • System Tweaking for decreased SSL Handshake times, improved loadbalancer latency, tcp keep-alive, and others
  • Increase monitoring using Telegraf+InfluxDB+Grafana

Software Developer

VarageSale
Sept 2014 - June 2017
  • Several large refactorings of Feed, Search, and User Permissions, including core business models and relationships
  • Consolidate Products from over 300k categories to ~1,000 categories using feature detection and classification techniques
  • Reduce JavaScript Compilation times from 3.5 minutes to less than one minute
  • Discover and Patch Security Holes for PCI compliance; correct CSRF protection

Full-Stack Developer

Willet Inc / SecondFunnel
August 2013 - Sept 2014
  • Worked on core landing pages product
  • Designed unique solutions for varying customer needs
  • Used gulp.js to build a more dynamic and fluid development cycle for front-end JavaScript
  • Setup a full deployment and provision architecture in Ansible for AWS

Backend Engineer

500px
Sept 2012 - June 2013
  • Built a recommendation engine for photos based on user segmentation using Python and GenSim
  • Security analysis and patching of main application (XSS, CSRF, SQL Injection)
  • Built portfolios product from the ground up, including front-end JS and backend Ruby on Rails

Design Engineer

Avvasi (acquired by NetScout)
May 2010 - Aug 2010, Jan 2011 - Dec 2011
  • Researched and developed high-speed logging and packet capture infrastructure (C++)
  • Media identification and extraction code for fragmented MPEG-4 (C++)
  • Silverlight Smooth Streaming identification and analysis for key QoS product (C++)
  • Implemented basis for high-speed database services on OSGi run-time platform (Java)
  • Code generation for data schema synchronization across multiple languages (Python,SQL,C++)

Education

University of Waterloo

Bachelor of Computer Science
Sept 2008 - August 2012
  • CS488 - Computer Graphics
  • CS452 - Real-Time Programming
  • CS444 - Compiler Construction

Skills

Ruby

  • Ruby on Rails (RoR)
  • Hanami
  • Rack
  • ActiveRecord

Python

  • Django
  • Flask

Elixir

  • Ecto
  • Phoenix

DevOps

  • Ansible
  • Salt
  • Linux
  • Docker

Datastores

  • Postgres
  • MySQL
  • Memcached
  • Redis
  • ElasticSearch
  • Kafka

Front-end Development

  • HTML
  • CSS
  • Javascript (ES6)
  • Webpack