Dionýz Lazar

July 2019 - present

Bringg (formerly Zenkraft) - Multi-Carrier Shipping Platform

Zenkraft provided shipping, tracking and returns directly in Salesforce, used by over 50,000 users. It was acquired by Bringg, a delivery management platform, in 2022. I joined as a contract Python engineer in 2019 to migrate the platform to Heroku/PostgreSQL, took ownership of the backend, and grew into Engineering Team Lead and, since April 2025, Director of Technology.

Carrier platform. Carrier coverage grew from about 25 to 221 integrations; I built 51 myself and scoped most of the rest. I wrote the framework that cut new integrations from weeks to days, and led the carrier API migrations forced by sunsets (UPS and FedEx SOAP to REST, USPS, Royal Mail, DHL Germany, Yodel to InPost) and regulatory changes (UK Windsor Framework, EU de minimis, US CPSC eFiling).

Heroku to GCP/Kubernetes. Led the migration: hosting cost fell by about half while shipment volume grew about 7x. I built observability from scratch (metrics, alerting, post-release checks) and used it to fix request hangs, 502s, pod crashes and DB deadlocks, taking production incidents from roughly monthly to about two a year.

Peak season. After a hard 2024 Black Friday, I replaced firefighting with capacity planning, autoscaling, batch shipment preparation and live metrics. The 2025 peak went smoothly.

Leadership. Grew the organisation from one team to three (about 11 people) and back to one. I now lead 4 senior engineers and 1 QA, all hired and mentored by me, including an engineer later promoted to Tech Lead. I report to executive leadership and am the main technical contact for carriers and customers.

AI enablement. Built Claude Code agents and skills for my team and others, including a self-service production data assistant that customer success and product use to answer customer questions without engineering help.

July 2018 - May 2019

Newchip - API for iOS app

Newchip is a FinTech startup that helps people to invest into other startups and I was hired as a Django API developer there.

Newchip's main focus was developing an iOS app and I was responsible for the API built on top of Django (DRF) running on Heroku. One of the efforts I was a part of was creating a dashboard for paid users. We built a dashboard which allowed the user (owner of a startup) to see analytics about their funding deal. The dashboard also allowed the user to edit information about their deal and it was integrated with the Chargebee subscription system.

I've learned a lot from this job in terms of agile software development, team work and leadership. It has given me a chance to grow professionally and to work with some very talented people.

July 2017 - October 2018

Sonder - Data Warehouse / ETL System

I was working with a US-based hospitality startup called Sonder as a Python Developer.

Their goal was to create a robust data pipeline able to collect from a multitude of different data sources. In the end, it was 43 different sources, some of them from open data platforms provided by the US government, some were web scraped. From the technical side, it was mostly my own effort to both architect and implement a flexible, robust and easily extensible data pipeline.

July 2017 - October 2018

IntrospectData - Data Ingestion Toolset

IntrospectData is a Data Science startup and I worked with them as a Flask API developer.

I was given a set of Swagger documents detailing multiple APIs that were designed to work in a microservice manner. My responsibility was then to implement these specs in Flask with the use of MongoDB.

I had a chance to work with a very talented, experienced developer, who has shown me a lot from DevOps, automation and CI/CD systems. This job has been one of my favorites so far, simply because of the amount of fun I had learning and working on this.