DATA ENGINEER

Nadhif Fathoni Hafiz

I’m a data engineer based in Jakarta, currently at Krom Bank. I work on data pipelines, CDC streaming, and the day-to-day reliability of our data platform.

Currently
Data Engineer · Krom BankOctober 2025 — present
Previously
DANA · TelkomselData engineering internships
Based in
Jakarta, Indonesia

01 Projects

PLATFORM ENGINEERING01
BEFORE120+generated scripts
AFTERYAML configsource onboarding
− ~15,000 lines+ reusable modules

KROM BANK ETL MODERNIZATION

ETL refactoring

I consolidated 120+ generated ETL scripts into shared modules, so adding a source only needs a YAML configuration change.

PythonETLYAML
Project details

The refactor removed around 15,000 lines of code (~92%) across multiple data sources. I rolled it out without production downtime.

ANALYTICAL PERFORMANCE02
QUERY LATENCY<1second

KROM BANK CLICKHOUSE CLOUD POC

ClickHouse Cloud PoC

I tested ClickHouse Cloud for fraud analytics, looking at query latency, storage costs, and how the data is organized.

ClickHouseSQLCompression
Project details

I worked with sorting keys, sparse primary indexes, and compression codecs. The PoC achieved sub-second queries and ~60% projected storage savings.

The storage figure is an estimate from the PoC.

REAL-TIME DATA03
Source DB
Kafka Connect
BigQuery
partitionsconnector tasksbatch sizes

KROM BANK STREAMING ARCHITECTURE

CDC streaming to BigQuery

I built a configurable CDC ingestion flow using Confluent Kafka Connect to move database changes into BigQuery.

ConfluentKafka ConnectBigQuery
Project details

I tuned Kafka partitions, connector tasks, and batch sizes for the existing ingestion workloads.

PERSONAL PROJECT04
AZURE BATCH PIPELINEFormula 1
INGESTTRANSFORMANALYZE

FORMULA 1 AZURE DATA PIPELINE

Formula 1 data pipeline

For this personal project, I used Azure Data Factory, Databricks, and Spark to process Formula 1 data, with the results stored in Azure Data Lake Storage.

DatabricksSparkAzure Data Factory
View on GitHub (opens in a new tab)

02 Experience

Download CV

Krom Bank

Data Engineer

CURRENT

OCT 2025 — PRESENT / JAKARTA, INDONESIA

  • Modernized ETL and CDC ingestion through reusable, config-driven architectures.
  • Built a severity framework for 500+ Airflow DAGs with Sev1–Sev4 SLAs and alert routing, reducing critical incident triage time by ~45%.
  • Evaluated ClickHouse for fraud analytics and created GCP, Airflow, and dbt dashboards for platform performance, cost, and usage.

DANA

Data Engineer Intern

JUL 2024 — OCT 2025 / JAKARTA, INDONESIA

  • Developed and maintained 50+ production pipelines using Apache Airflow and Alibaba MaxCompute.
  • Built compute and cost monitoring that improved incident response by 60% and reduced unexpected compute costs by 15%.
  • Supported dimensional remodeling of data marts serving ~80% of business needs.

Telkomsel

Data Engineer Intern

FEB 2024 — JUN 2024 / JAKARTA, INDONESIA

  • Built an end-to-end MySQL-to-warehouse pipeline with Apache Airflow for the Radio Transport Power Engineering division.
  • Improved planning and tracking efficiency by 80% through automated delivery to Power BI dashboards, Telegram bots, and reporting tools.

03 About me

I started in data engineering through internships at Telkomsel and DANA, then joined Krom Bank in 2025.

A lot of my work is improving systems that already exist: untangling ETL scripts, tuning ingestion, and making it easier to spot problems when something breaks.

Bachelor of Computer ScienceBINUS University · 2021–2025GPA 3.66 / 4.00

Technical skills

Languages & foundations

PythonSQLBashGit

Data & orchestration

Apache AirflowdbtConfluentBigQueryClickHouseMaxComputePostgreSQL

Cloud & infrastructure

Google CloudAlibaba CloudDockerKubernetes

Project toolkit

Azure Data FactoryDatabricksApache SparkADLS

Contact

You can reach me by email or on LinkedIn.