Senior Data Engineer - Recommendations

True Software Scandinavia AB; Stockholms kommun; On-site; SEK 900,000 - 1,200,000; Full time

Benefits offered by this job

30 days paid vacation

Private health insurance

Pension contributions

Wellness budget

Job summary

Truecaller is seeking a Senior Data Engineer to own the data foundation behind our recommendations and adVantage ML systems. You will build feature pipelines, streaming ingestions, training datasets, and real-time feature serving for millions of users.

This hands-on platform role sits at the intersection of large-scale data engineering and production ML, collaborating with data scientists to move models from notebook to production and ensuring data contracts and freshness SLAs.

Qualifications

• Strong programming in Python and Spark; build complex ETL/ELT pipelines.
• Hands-on experience with an orchestration tool such as Airflow for production workloads.
• Experience with large datasets on a major cloud provider (GCP preferred; AWS/Azure also fine).
• Solid software engineering fundamentals: testing, CI/CD, and maintainable code.
• Ability to work with data scientists and ML engineers and understand data needs for production ML.
• Excellent problem-solving and communication skills; self-motivated to own problems end to end.

Responsibilities

• Build and own feature and training-data pipelines for retrieval, ranking, and contextual-bandit models.
• Design streaming pipelines to capture impressions, clicks, conversions for near real time retraining.
• Stand up and maintain a real-time feature store for consistency between offline training and online inference.
• Own ad-event and attribution data backbone: clean, reconciled pipelines for delivery and billing.
• Partner with data scientists to move models from notebook to production; manage data contracts and SLAs.

Skills

Python

Spark

CI/CD

Problem solving

Communication

Kubernetes

Tools

Airflow

Git/Jenkins

BigQuery

GCP/AWS/Azure

Kafka/Streaming

Job description

The role:

As a Senior Data Engineer on our Recommendations and adVantage teams, you will build and own the data foundation behind Truecaller’s recommendation and advertising ML systems. That means the feature pipelines, streaming event ingestion, training datasets, and real‑time feature serving that power the retrieval, ranking, and contextual‑bandit models deciding what hundreds of millions of users see. This is a hands‑on platform role at the point where large‑scale data engineering meets production machine learning.

What you’ll do:

• Build and own the feature and training‑data pipelines behind our retrieval, ranking, and contextual‑bandit models, taking raw events all the way to model‑ready features.
• Design streaming pipelines that close the loop between serving and learning, capturing impressions, clicks, and conversions in near real time so models retrain on fresh signal.
• Stand up and maintain a real‑time feature store so features stay consistent between offline training and low‑latency online inference.
• Own the ad‑event and attribution data backbone: clean, reconciled pipelines for delivery, billing, and third‑party attribution partners.
• Partner directly with data scientists to move models from notebook to production, owning the data contracts, freshness SLAs, and lineage they depend on.
• Build reusable, config‑driven frameworks so new models and campaigns onboard without bespoke pipeline work each time.
• Keep the platform reliable at scale: billions of events daily within defined SLAs, backed by monitoring, data‑quality checks, and dependable backfills.
• Set best practices and processes around pipeline design, testing, and data modeling across the team.

What you bring in:

• Strong programming skills in Python and Spark, with a track record of building complex, large‑scale ETL/ELT pipelines.
• Hands‑on experience with an orchestration tool such as Airflow, feeding ML or analytics workloads in production.
• Experience working with large datasets on a major cloud provider (GCP preferred; AWS or Azure also fine).
• Solid software engineering fundamentals: testing, CI/CD with Git and Jenkins or similar, and code you would be happy to maintain.
• Comfort working shoulder to shoulder with data scientists and ML engineers, and a clear understanding of what production ML needs from data – features, freshness, consistency, and lineage.
• Excellent problem‑solving and communication skills, and the self‑motivation to own problems end to end.

It would be great if you also have:

• Experience with streaming systems such as Kafka, Flink, or Spark Structured Streaming.
• Experience with a feature store (Feast, Vertex AI, Tecton, or in‑house).
• Exposure to recommendation, ranking, or ads from ML systems and the data they rely on.
• Knowledge of Kubernetes.
• Experience managing a data warehouse in BigQuery (preferred) or Redshift.

What we offer:

We support growth through learning resources, leadership programs, mentoring, and real hands‑on work. People can move between teams and projects to build new skills and keep things interesting. We offer clear internal mobility and a transparent path for progression, with leaders who stay involved and provide guidance throughout the year. In addition, you will benefit from:

• A comprehensive compensation package: We offer a competitive salary, 30 days of paid vacation, private health insurance, parental leave top‑up, pension, and wellness contributions.
• Modern tools to do your best work: Choose your preferred computer and phone within our budget, so you can work comfortably and efficiently.
• A people‑focused office culture: We value in‑person collaboration and follow an office‑first model, with some flexibility. Our offices offer a vibrant environment with opportunities to learn, connect, and recharge, from breakfast, lunch, and well‑stocked snack stations and quiet spaces to team activities such as movie nights, tech meetups, and cultural events. There’s something for everyone.
• Truecaller’s “Lab Days”: offer a space for imagination: 5 times per year for 3 days, where everyone steps away from their normal tasks to explore new, bold ideas and build things they’ve always wanted to. It’s a space where curiosity leads the way, and prototypes take shape. Some concepts even make it into production, and a few have grown into real features used by millions today. Lab Days allow you to be creative, learn fast, and help shape Truecaller’s future.

Come as you are:

Truecaller is committed to building a diverse and inclusive team. We believe that a wide range of backgrounds, perspectives, and experiences strengthens our products and our culture. No matter where you're from, what language you speak, or how you identify, we value what makes you unique and would love to get to know you.

Check out Life at Truecaller - Behind the code:

https://www.instagram.com/lifeattruecaller/

We only accept applications in English.

As part of the recruitment process, we will conduct a background check.