Julian Calleja

Data engineering for iGaming teams that need it done properly.

What I've Built

Lakehouse Data Platform Rebuild

Elantil

Leading the ground-up rebuild of a B2B iGaming data platform — Kafka streaming into AWS Glue, Apache Iceberg tables, Athena, and dbt Bronze/Silver/Gold layers. Shifted decision-making from gut-feel to evidence-based, presented directly to C-level and key clients.

59.5% throughput increase 10.4% faster execution

Data Migration Framework

Gaming Innovation Group (GiG)

Designed and delivered a migration solution that enabled GiG to onboard large, established operators with existing customer bases. Migrated 20,000+ customer records in under 30 minutes.

20,000+ records < 30 min migration
Read the case study → Referenced in GiG's Q1 2024 earnings call →

Broker CRM — Real-Time Pipeline

Gaming Innovation Group (GiG)

Built a real-time CRM data pipeline delivering live player events to platforms like Symplify, enabling 10+ operator clients to trigger personalised actions based on real-time behaviour.

300k events/hour 10+ operator clients
Read the case study →

6TB Data Warehouse Migration

SpinCity Solutions

Took a BI team from being unable to query historical data to full analytical access across a 6+ TB dataset in under 20 minutes, by designing an ETL pipeline onto S3.

6+ TB migrated < 20 min query time
Read the case study →

Where I've Worked

Elantil

Head of Data Platform · 2024–Present

Ground-up lakehouse rebuild on Iceberg and Kafka — 59.5% throughput increase, 10.4% faster execution, presented directly to C-level and key clients.

SpinCity Solutions

Data Architect · 2024

6+ TB of unqueryable history moved off production to S3 in under three months — full analytical access in under 20 minutes, for under €300 a month.

Gaming Innovation Group

Data Engineer → Senior · 2019–2024

Real-time data products for 10+ operators: 300k events an hour through the CRM pipeline, 20,000+ player records migrated in under 30 minutes, referenced in GiG's Q1 2024 earnings call.

Bit8

QA Engineer · 2018–2019

First iGaming role. Built the platform's test automation foundation.

Verticals I've Worked Across

Casino Sports Betting Lottery Crypto Gambling Affiliate Marketing Player Acquisition B2B Platform B2C Operator

What I Build With

Streaming & ingestion

Kafka · Apache NiFi

Storage & query

Apache Iceberg · Amazon S3 · Athena

Transformation

dbt · AWS Glue

Layering

Bronze / Silver / Gold lakehouse

Working on something I could help with?

Always up for a conversation about a project or a tricky technical challenge.