Konstantinos Kasidiaris

Proactive engineer who prefers building infrastructure rather than fighting fires. Enjoys Everything as Code (EaC) and automates processes, empowering teams to deliver value faster with minimal friction.

[email protected] GitHub LinkedIn X Website

Work Experience

Software Engineer

Freelancer • Turnkey Solutions

Remote

09.2024 - present

  • Developed ergolabos.gr, a construction materials marketplace.
  • Developed xot.gr, a static website for a local nonprofit organization.
Elixir Phoenix LiveView Tailwind PostgreSQL Render Hugo Docker Devcontainers GitHub Actions FFmpeg Copilot Cloudflare

Software Engineer

Blueground • PropTech

Remote

11.2021 - 08.2024

  • Worked primarily on the Backend for Frontend (BFF) service.
  • Optimized database queries and indexes leading to ~30% average reduction in P90 and ~50% average reduction in P99.
  • Implemented various code optimizations that increased website capacity from 90 rps to ~500 rps.
  • Took initiative to fix flaky integration test suites, improving reliability from a 70% failure rate to 99.9% test pass confidence.
  • Designed and implemented a robust inbox pattern, ensuring no messages were missed.
  • Assisted the platform team in creating playbooks for different alerts of the BFF app.
  • Created a Dashboard-as-Code solution in Datadog to help the business monitor various integration metrics.
  • Standardized logging practices across the service.
  • Migrated RabbitMQ integration to Kafka.
  • Integrated partners' systems into the platform.
  • Mirrored business pricing logic in the website for near-instant customer pricing results.
  • Implemented wishlists.
  • Served as the go-to person for upgrading runtimes and libraries.
Node.js Express Fastify Vue Jest Bullmq Docker Testcontainers Cypress Datadog Redis MongoDB Kafka RabbitMQ TypeScript Git

Backend Developer

Desquared • Software Agency

Remote

07.2020 - 11.2021

  • Worked mainly on the BOX food delivery application, responsible for creating and maintaining backend services. Contributed significantly to stabilizing the product.
  • Implemented SSE in the ordering system, resulting in a two-thirds reduction in required servers (from 3 Performance-L instances to 1), saving approximately $1,000 per month.
  • Implemented Node.js clustering, resulting in a $2,500 monthly reduction in operational costs while average weekly orders doubled.
  • Refactored BOX code to one-third of its original size (120k to 47k lines of code) and halved its volume (98.7 MB to 56.2 MB).
  • Optimized database queries and indexes, leading to an average ~55% reduction in P90 latency.
  • Onboarded and trained four backend engineers.
  • Standardized logging practices.
  • Introduced a deterministic test suite and a linter, improving code quality and consistency.
  • Served as the go-to person for upgrading runtimes and libraries.
Node.js Express MongoDB Mongoose Jest Redis Heroku Git

Software Engineer

Interamerican • InsurTech

Athens, GR

07.2018 - 07.2020

  • Developed portlets to improve insurance agents' daily workflows.
  • Led cross-team knowledge transfer on portlets, improving developer experience.
Java Apache Wicket Groovy Spock SVN Gradle DB2

Chemical Engineer

C&A Stavros Kassidiaris S.A. • Shipbuilding Automations

Piraeus, GR

12.2016 - 12.2017

  • Monitored processes and ensured compliance with Greek, European, and IMO environmental regulations.
  • Played a leading role in the transition from ISO 9001:2008 to 9001:2015.
  • Designed new business cards and email signatures, leading to a more professional company profile.

Chemical Engineer Intern

Gaiatech • Wastewater Treatment

Tripolis, GR

06.2011 - 08.2011

  • Studied the wastewater treatment plants of Tripolis, Vytina, Astros, and Agioi Theodoroi (Korinthia).

Education

Full Stack Java Developer

AFDEmp - Peoplecert • Athens, GR • 2018

Chemical Engineer (BEng-MEng)

University of Patras • Patras, GR • 2018

Personal Projects

ergolabos

Construction materials marketplace.

Elixir Phoenix LiveView Tailwind PostgreSQL Docker

pestimate

Showcase of company products on Android and iOS.

Angular Apache Cordova Spring Boot PostgreSQL

Public Talks

Engineers Anonymous: Similar stack, different outcomes

DevOops Athens • 2024-12-19

A philosophical reflection of what ultimately makes handling a difficult situation effective.

View Event

Languages

Greek - Native proficiency
English - C2 (Full professional proficiency)
Download Resume