I learn by building

Below are some of my projects, which are still available online. As a practitioner, when I learn about a new technology, I don't apply it to client work right away. First, I build at least one real product with it to see if it’s good enough for a production environment.

Otelic.com

The Idea

To give developers access to production logs and traces without needing direct server SSH access. It’s an observability platform for any application using OpenTelemetry libraries, designed to centralize metrics, traces, and logs in one place.

The Execution

A platform built on top of the OpenTelemetry open-source standard. It receives telemetry data, allowing developers to browse and analyze application behavior through a clean web interface.

Tech Stack

TypeScriptReactReact QueryTailwind CSSMongoDBClickHouse

Oisie.com

The Idea

To build a marketing automation tool like Klaviyo. It allows non-technical team members to create powerful, event-driven email sequences and segment users based on their in-app behavior.

The Execution

A system where developers define events, and marketers build automation flows. It can send targeted emails or trigger webhooks based on what users do (or don't do).

Tech Stack

TypeScriptNode.jsReactNext.jsMongoDB

Leadpurify.com

The Idea

To create a simple, fast tool for validating email lists. Email lists degrade over time, and sending to invalid addresses hurts deliverability. This service ensures a list is clean before a campaign is sent.

The Execution

A service where users upload a CSV of contacts. The backend parses data, extracts social links, performs live SMTP checks to verify each email address, and returns a clean, verified file.

Tech Stack

TypeScriptReactNode.jsMongoDBAPI Integrations
Lukas Liesis | Elite Software Engineer for Founders