Data Engineer vs Data Scientist: How to Make the Right Hire

In today’s data-driven business landscape, the choice who to hire – a data engineer vs data scientist – has become increasingly crucial. Due to the global digital transformation and the AI megatrend, a vast amount of companies have begun to prioritise data. In fact, this year’s AI & Data Leadership Executive Benchmark Survey reports that […]

by Aleksandrina Vasileva

February 19, 2025

10 min read

data-engineer-vs- data-science-dreamix

In today's data-driven business landscape, the choice who to hire - a data engineer vs data scientist - has become increasingly crucial. Due to the global digital transformation and the AI megatrend, a vast amount of companies have begun to prioritise data. In fact, this year's AI & Data Leadership Executive Benchmark Survey reports that "investments in data and AI are a top organisational priority for 91% of companies" and that AI's "halo effect" on data, has urged 94% of respondents to focus even more on data. 

Putting data at the center of attention has created a complex decision-making environment for business leaders, particularly when it comes to building their data teams. While both data engineers and data scientists work with data, their roles have a somewhat symbiotic relationship and differ in their day-to-day tasks. In this article, we’ll shed some light on the key differences between these two key data professionals, the different purposes each of them has in an organisation's data ecosystem. We'll conclude by examining key business scenarios that inform the strategic decision between hiring a data engineer versus a data scientist.

Data engineer vs data scientist: understanding today's data roles

“Enterprises are finally tapping into their unstructured data”, Snowflake’s Data Trends Report suggests. Such data hides massive business potential, ready to be discovered and used to improve operations, eliminate potential data-related risks but also innovate. 

The sheer amount as well as the complexity of modern data operations demands a clear understanding of how data engineers and data scientists contribute to an organisation's success. While these roles sound similar at first glance, they serve distinct yet complementary purposes in the data ecosystem. But without knowing what sets apart data engineers from data scientists, many organisations make the costly mistake of hiring a data scientist when they actually need a data engineer first, or vice versa.

Without proper data infrastructure and pipelines that data engineers provide, even the most skilled data scientist will struggle to deliver value. Conversely, having robust data infrastructure without the analytical expertise of a data scientist means missing out on valuable insights that could drive business growth. 

True business intelligence emerges when your data foundation is solid. While many organisations claim to be data-driven, the quality of your decisions can only match the quality of your data infrastructure. As a leader, investing in proper data collection and management, you're not just gathering information means you're building the cornerstone of strategic advantage and sustainable growth.

Let’s examine each of these data professionals’s areas of expertise and responsibilities more closely:

Data engineer’s key responsibilities

Data engineers are the architects of data infrastructure, responsible for building and maintaining the foundation that enables effective data analysis. Data engineers play a crucial role in data preparation, ensuring data quality through comprehensive cleansing processes that address issues such as missing values, data corruption, and inconsistent data formatting.

A significant portion of this preparation occurs during the ETL (Extract, Transform, Load) pipeline, where data undergoes various transformation and optimisation procedures. Once processed, this refined data is transferred to cloud-based data warehouses, where it can be enriched through integration with additional datasets to enhance its analytical value. Building and executing ETL processes is an example of technical expertise but let’s see what else falls into a data engineer’s area of responsibility:

Infrastructure development 

Data engineers design and implement scalable data pipelines, create robust data storage solutions while ensuring system’s reliability and performance. They’re also responsible for developing data integration frameworks.

Technical responsibilities

Building ETL processes, implementing data security protocols are some key role responsibilities. A data engineer is further responsible for managing data warehousing solutions, creating and maintaining APIs for data access. Last but not least, data engineers need to find ways to constantly improve database performance and data accessibility

Quality assurance 

In the QA realm, data engineers need to ensure data accuracy and consistency, and implement data validation processes. They also need to maintain high data governance standards and monitoring system performance.

Data scientist’s key areas of responsibility

Data scientists are analytical specialists who transform raw data into actionable business insights. Their key territory expertise leans more towards business-focused tasks and spans over several crucial areas:

Analytics and modeling 

Data scientists develop predictive models and conduct statistical analysis. Although not necessarily, data scientists can work on creating machine learning algorithms and AI model development when the use case is present. They’re also accountable for developing hypotheses (null & alternative) and testing methodologies (A/B testing, multivariate, Chi-square Tests, etc.) 

Business intelligence (BI) 

Within the realm of business intelligence, data scientists play a pivotal role by focusing on several interconnected responsibilities. Their primary function involves identifying meaningful trends and patterns within vast datasets, enabling organisations to understand underlying business dynamics and customer behaviors. Through sophisticated pattern recognition and statistical analysis, they uncover hidden correlations that might otherwise go unnoticed. 

Later on, they can design robust forecasting models that help organisations prepare for future trends, market shifts, and tap into new business opportunities. These predictive models combine historical data with current market indicators to provide accurate projections that guide strategic decision-making. Another crucial BI aspect of a data scientist role involves 

Perhaps most importantly, data scientists excel at converting complex analytical findings into actionable business insights. They bridge the gap between raw data analysis and practical business applications, translating statistical findings into concrete recommendations that drive strategic initiatives. 

Strategic communication

Data scientists communicate with business stakeholders proposing strategic actionable insights backed up by data. Besides, they’re also responsible for developing comprehensive data visualisation solutions. From interactive dashboards to detailed reports and comprehensive analytical reports allows them to translate complex data patterns and make them easily accessible to non-technical professionals.

Data engineer vs data scientist: Business impact and value creation

Let's break down how data engineers and data scientists bring different kinds of value to the table, and more importantly, how they can impact your business. You can think of data engineers as your behind-the-scenes efficiency masters. They're the ones making sure your data systems run like a well-oiled machine, cutting down on those frustrating system delays and preventing costly data mishaps. When you've got a solid data engineer on board, you'll see the difference in smoother operations, faster data processing, and significant cost savings on your infrastructure - essentially, they help you do more with less.

Now, data scientists are your forward-facing value creators. They're the ones who can tell you which customers are likely to churn next month, where you're leaving money on the table with your pricing, or which market segment you should target next. Their impact shows up directly in your revenue numbers, whether that's through spotting new opportunities, optimizing your current operations, or helping you stay ahead of market trends. When your executives need to make big decisions, it's your data scientists who provide the concrete evidence to back those choices up.

It’s as if the data engineer builds the highway, and the data scientist drives the cars that deliver business value. Without a good highway, even the best driver can't get anywhere fast. And without skilled drivers, even the best highway isn't generating value. When you get both right,  that’s when the magic happens. As an end result, your business doesn’t only cut down on operational costs, you're also actively growing your business with data-driven precision. 

Our team of data experts can help you evaluate your current data capabilities and identify the right data strategy for your business objectives.

Data engineer vs data scientist: When do you need them

Now that we’ve covered the main areas of responsibility for both data engineers and data scientists, we can discuss when your business needs each of these professionals.

It’s time to hire data engineers when you have:

  • Growing data volume challenges

Let’s review a business example from aviation, one of the key domains expertise of Dreamix. A single commercial aircraft generates up to 844TB of data per flight through various sensors monitoring everything from engine performance to cabin pressure. When an airline operates hundreds of flights daily, this creates an enormous data processing challenge that requires sophisticated infrastructure to handle real-time analysis. To solve this problem, an experienced data engineer might do an implementation with Apache Kafka or similar streaming platforms for real-time data ingestion. Additionally, creating distributed processing systems using robust technologies like Apache Spark for handling massive data streams. 

  • Integration bottlenecks

Integration bottlenecks, if not handled properly, can cause major business disruptions. When you hire skilled data engineers, they can design secure data integration architecture using edge computing or data tiering. A data engineer can also addresses API-related challenges by developing custom API solutions and conducting complex API orchestration. 

  • Performance issues

Another key business indicator that you’re in need of a data engineer is when performance issues begin to arise. Let’s stay on the example with aviation, and more specifically airlines where real-time performance is crucial. Flight operators need immediate access to aircraft performance data, weather updates, and maintenance records to make quick but data-driven decisions about flight safety and operations. In this case, a data engineer could implement in-memory key-value databases (like Redis) for instant access to critical flight data as well as data partitioning strategies to optimise query performance.

  • Data quality concerns

Data quality concerns become critical when inconsistent or incorrect data leads to flawed business decisions. Take a healthcare provider managing patient records across multiple facilities as a real-world example. Duplicate records, inconsistent formatting, or missing critical information can impact patient care quality and possibly even cause regulatory compliance concerns. This is why data engineers implement validation rules, standardisation processes, and quality monitoring systems to maintain data integrity.

Related: Data Engineer Salary Ranges By Country & Experience

It’s time to hire data scientists when you have:

  • Need for predictive capabilities

When businesses need to be prepared and stay resilient to shifting market trends, data scientists become crucial. For example, in the aviation industry, a data scientist might develop models predicting aircraft maintenance needs based on sensor data patterns. Or, they can create algorithms to forecast passenger demand for specific routes. Data scientists can also provide business value by building predictive systems for fuel consumption optimisation - contributing to both operational optimisation and aviation sustainability.  

  • High customer behavior analysis requirements

Uncovering patterns in customer behavior and derive business value from data is another data scientist key capability. In practice, this means analysing passenger booking patterns to optimise dynamic pricing strategies. This can happen through NDC and Offer and Order, some of the major aviation technology trends for 2025, or by creating personalised marketing recommendations based available historical data.

  • Market optimisation opportunities

Business-wise, skillful data scientists also contribute with market optimisation strategies. For instnce, by dentifying optimal route networks based on passenger demand patterns or analysing competitor pricing strategies, they help companies optimise revenue.

  • Strategic planning needs

Data scientists support long-term business strategic decisions through crafting scenario modeling tools for fleet expansion decisions or forecasting models for new routes or services. They can also develop market share analysis tools to identify key growth opportunities. Last but not least, by analysing long-term trends they help C-level executinves make informed strategic investments in the right technologies. 

Now that you know when you need data engineers and when data scientists, here is an example integration roadmap. 

Data-Engineer-vs-Data-Scientist-dreamix

As a business owner or executive, the choice between these roles should align with your current data maturity, immediate business needs, and long-term strategic objectives. Consider your 

organisation's immediate pain points: if you're struggling with data gathering, accessibility and system performance, a data engineer might be your priority hire. If you're looking to leverage existing data for predictive insights and strategic planning, a data scientist could be the right fit to unlock more business value. 

Data engineer vs data scientist: Making your strategic choice

Hopefully, you’re now more aware what sets apart data engineers vs data scientists. is more than just a technical consideration – it's a strategic business decision that impacts your organisation's data capabilities and competitive advantage. While data engineers build and optimise the robust infrastructure essential for handling today's data volumes, data scientists transform this foundation into actionable business insights that drive growth and innovation. 

As presented on the first infographic, the ROI timeline and impact vary significantly when complying data engineer vs data scientist. Data engineers typically deliver value within three to six months primarily through improved data accessibility, reduced processing times, and enhanced system reliability. Data scientists, on the other hand, often show impact within six to twelve months through revenue optimisation, enhanced customer insights, and strategic decision support.

Ultimately, making the right choice between a data engineer and a data scientist will largely depends on your organisation's specific needs, goals as well as the maturity of its data infrastructure.  Your end decision should be guided by a clear understanding of the current challenges and future business objectives and a solid data strategy, ensuring that the hire aligns with the long-term vision and immediate priorities of your business. Whenever possible, balancing both data-related roles will provide a comprehensive approach to leveraging data as a strategic asset.

Ready to embark on your next data science project? Let's discuss your data strategy and discover how we can help you build a data science team and drive real business value together.

Aleksandrina a thought leader in Dreamix with 5+ years experience in the custom software development, AI and innovations across aviation, healthcare, logistics and fintech. With high business expertise in the DACH region, she converts real high tech business knowledge into written insights aiming to help executives and IT professionals bridge the gap between innovation and implementation through practical, experience-driven insights.