About me

I'm Julian Calleja — Head of Data Platform at Elantil, based in Malta. I build the real-time data platforms iGaming operators run on, and I care as much about the decisions the data drives as the pipelines underneath it.

Get in touch


Now: Elantil

I lead Elantil's data platform — a ground-up lakehouse rebuild on Apache Iceberg, with Kafka streaming into AWS Glue, Athena for querying, and dbt handling the Bronze/Silver/Gold transformation layers. Open table formats, event-driven, built to outlast any single vendor.

The technical work is only half the story. The rebuild shifted how the company makes decisions - from gut-feel to evidence - and I've presented the platform directly to C-level and key clients. That's the part I optimise for: data that changes what the business does, not dashboards nobody opens.

Before: GiG (2019–2024)

I spent five years at Gaming Innovation Group, progressing from Data Engineer in Test to Senior Data Engineer during the early days of GiG Data, their real-time data product. Two highlights:

The data migration framework - I led it from requirements to delivery. It let GiG onboard large, established operators, moving 20,000+ customer records (balances, consents, profiles) in under 30 minutes, and was referenced in GiG's Q1 2024 earnings call as a new revenue opportunity.

Broker CRM - a real-time pipeline I initiated and built, delivering live player events to platforms like Symplify. It scaled from zero to 300k events per hour across 10+ operator clients.

In between GiG and Elantil, a stint as Data Architect at SpinCity Solutions: I took a BI team from zero historical access to querying a 6+ TB dataset in under 20 minutes.

On the side

I ran experimental iGaming affiliate projects — crypto gambling, competitive intelligence, player acquisition — which means I see the market from the operator's side, not just the platform's. It's a perspective most data engineers don't have, and it shapes how I connect infrastructure to commercial outcomes.

Outside of work

I lead the Rabat Scout Group in Malta — planning, coordination, and mentoring young people. It's a different kind of leadership: patience, communication, and building something that lasts beyond any one project. Beyond that: reading, hiking, camping.


Common questions

Do you only work in iGaming? Primarily, yes. Seven years focused on casino, sports betting, lottery, and crypto gambling means I understand the domain, the data, and the regulatory landscape in ways a generalist doesn't. The systems themselves — real-time pipelines, event-driven architectures, lakehouse platforms — transfer anywhere.

What's your current stack? Kafka for streaming, AWS Glue for ingestion, Apache Iceberg tables, Athena (Trino) for querying, and dbt for Bronze/Silver/Gold transformations. Java where it counts. Open formats first — the data outlives the tooling.

Are you open to freelance or consulting work? I'm open to conversations, short engagements or longer-term. Start with a LinkedIn message or an email.

What makes your approach different? I don't just build pipelines. I think about who uses the data, what decisions it drives, and how it connects to product and commercial outcomes. Building infrastructure professionally while operating in the market independently is what shapes that thinking.


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.