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Roles directory / AI & ML

Machine Learning Engineer


Machine learning engineers build and deploy machine learning models to solve business problems. They design and implement algorithms, train models, and optimize them for performance.

Also known as:
ML Engineer, Applied ML Engineer


Typical years of experience


Machine Learning Engineer

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What is machine learning?

At its core, machine learning is a subset of artificial intelligence (AI) that focuses on enabling computers to learn and improve from data without being explicitly programmed.

Machine learning algorithms learn patterns and relationships from vast amounts of data, allowing systems to make predictions, identify trends, and solve complex problems. This ability to learn from data is what sets machine learning apart from traditional rule-based programming approaches.

The field of machine learning encompasses a wide range of methodologies, including supervised learning, unsupervised learning, and reinforcement learning. Each approach has its own set of applications and techniques which cater to different types of problems and data.

What does a machine learning engineer do?

Machine learning engineers are the driving force behind the development and implementation of machine learning models and algorithms. Let’s delve into the specific responsibilities and tasks that machine learning engineers undertake.

Data Preparation

One of the foundational tasks of a machine learning engineer is data preparation. This involves gathering, cleaning, and organizing large amounts of data in a way that’s suitable for training machine learning models. Machine learning algorithms rely heavily on high-quality data, and the process of data preprocessing ensures that the data is in a usable format. This may involve tasks such as handling missing values, normalizing data, and transforming features.

Algorithm Design and Selection

Machine learning engineers are responsible for selecting or designing the most appropriate algorithms for a specific task. They analyze the problem domain, the available data, and the desired outcomes to determine the best approach. This involves choosing the right type of algorithm, such as decision trees, support vector machines, or deep neural networks. Additionally, they must consider hyperparameter tuning, selecting appropriate loss functions, and optimization algorithms to train the models effectively.

Model Training and Evaluation

Once the algorithm is selected or designed, machine learning engineers train the models using the prepared data. They iterate through training cycles, adjusting the model’s parameters and hyperparameters to optimize its performance. Then, they evaluate the model‘s performance using various metrics, such as accuracy, precision, or recall. This evaluation helps assess the model’s effectiveness and guides further improvements or iterations.

Deployment and Integration

The final step in the machine learning engineer’s workflow is deploying the trained model in a production environment. This involves integrating the model into larger systems or applications, ensuring its compatibility and scalability. Machine learning engineers must address considerations such as real-time processing, efficient data storage, and handling new incoming data. They work closely with software engineers and DevOps teams to ensure smooth deployment and monitor the model’s performance in real-world scenarios.

What kinds of companies hire machine learning engineers?

The demand for machine learning engineers has skyrocketed as organizations across various industries recognize the immense value that machine learning can bring to their operations. In HackerRank’s 2023 Developer Skills Report, machine learning dominated the list of most in-demand skills, second only to problem solving. Hiring for machine learning engineers is only expected to accelerate in the years to come. The main industries hiring machine learning engineers include tech, manufacturing, finance, health care, life sciences, transportation, and retail. 

It’s worth noting that machine learning engineers can also find opportunities in consulting firms and research institutions, where they contribute to cutting-edge projects, collaborate with domain experts, and drive innovation across various industries.

Machine learning engineer salary and job outlook

On average, machine learning engineers receive highly competitive compensation packages. However, sources on tech salaries often present different and at times conflicting numbers. Estimates for the average base salary for machine learning engineers in the U.S. range from $151,939 to $240,000. Salaries will vary depending on experience, skills, industry, location, and company size.

The job outlook for machine learning engineers is equally promising. From 2021 to 2031, the U.S. Bureau of Labor Statistics projects the number of employed software developers, quality assurance analysts, and testers in the U.S. to grow by 25%.

As machine learning is still a maturing field, the role of machine learning engineers will continue to evolve. Machine learning engineers will play a critical role in the development of the world’s most exciting technologies, including, artificial intelligence, the internet of things, and autonomous vehicles.

Machine learning engineer skills & qualifications


Proficiency in programming languages is a must-have skill for machine learning engineers. Python is a popular choice due to its rich ecosystem of libraries and frameworks specifically designed for machine learning tasks. Java and C++ are also used in certain contexts. Machine learning engineers should be comfortable writing clean, efficient, and scalable code. They should understand key concepts like object-oriented programming, data structures, and algorithms.

Data handling and visualization

Machine learning engineers work extensively with data sets of varying sizes and complexity. They need to be skilled in data handling, including data preprocessing, data augmentation, and feature engineering. Proficiency in data visualization tools, such as Power BI, Tableau, or Alteryx, is valuable for gaining insights from data and communicating findings effectively.

Neural networks

Machine learning engineers should have a strong understanding of neural networks and their architectures. This includes knowledge of different types of neural networks like feedforward networks, convolutional neural networks, recurrent neural networks, and multilayer perceptrons. They need to understand activation functions, backpropagation, and regularization techniques. Deep learning frameworks like TensorFlow, PyTorch, and Keras are essential tools for implementing and training neural network models.


A strong foundation in applied mathematics is crucial for understanding the underlying concepts of machine learning. Linear algebra, calculus, and probability theory are fundamental mathematical frameworks used in developing and analyzing machine learning algorithms. Knowledge of linear algebra helps in understanding matrix operations, while calculus is essential for optimization algorithms. Probability theory enables machine learning engineers to work with probabilistic models and make statistical inferences from data.

Problem solving and critical thinking

Machine learning engineers should have excellent problem-solving and critical-thinking abilities. They need to decompose complex problems into smaller, manageable components and develop creative solutions for each component. They must be able to analyze and interpret results, make informed decisions, and iterate on their approaches based on feedback and performance evaluations.

Experience & education

After competency, the most important qualification for machine learning engineers is experience. On-the-job experience and training is a critical requirement for many employers.

Then there’s education. About 75% of developers worldwide have a bachelor’s degree or higher. If you’re recruiting, screening, or hiring engineers, there’s a high likelihood that many of them will have a degree. And many companies still require engineers to hold four-year degrees. 

However, experience and training outside of higher education can equally prepare a candidate to succeed in a machine learning engineering role. Research has shown that 86.7% of developers have taught themselves a language, framework or tool outside of a classroom or course. And bootcamps and online training are popular ways to learn new technical skills.

Machine learning trends

In the fast-paced realm of machine learning, staying up to date with the latest trends is paramount. The landscape is constantly evolving, with advancements in algorithms, data gathering, and processing power pushing the machine learning discipline forward.

Automated Machine Learning 

Automated machine learning, or AutoML, is one of the most significant machine learning trends. Roughly 61% of decision makers in companies utilizing AI said they’ve adopted autoML, and another 25% were planning to implement it that year. This innovation is reshaping the process of building ML models by automating some of its most complex aspects.

AutoML is not about eliminating the need for coding, as is the case with no-code ML platforms. Instead, AutoML focuses on the automation of tasks that often require a high level of expertise and a significant time investment. These tasks include data preprocessing, feature selection, and hyperparameter tuning, to name a few.

Tiny Machine Learning 

Tiny machine learning, commonly known as TinyML, is another significant trend that’s worth our attention. It’s predicted that tinyML device installs will increase from nearly 2 billion in 2022 to over 11 billion in 2027. Driving this trend is tinyML’s power to bring machine learning capabilities to small, low-power devices, often referred to as edge devices.

The idea behind TinyML is to run machine learning algorithms on devices with minimal computational resources, such as microcontrollers in small appliances, wearable devices, and Internet of Things (IoT) devices. This represents a shift away from cloud-based computation toward local, on-device computation, providing benefits such as speed, privacy, and reduced power consumption.

Generative AI

Generative AI has dominated the headlines in 2023. Since the release of OpenAI’s ChatGPT in November 2022, we’ve seen a wave of new generative AI technologies from major tech companies like Microsoft, Google, Adobe, Qualcomm, as well as countless other innovations from companies of every size. These sophisticated models have unlocked unprecedented possibilities in numerous fields, from art and design to data augmentation and coding.

Generative AI, as a branch of machine learning, is focused on creating new content. It’s akin to giving an AI a form of imagination. These algorithms, through various techniques, learn the underlying patterns of the data they are trained on and can generate new, original content that mirrors those patterns.

No-Code Machine Learning

Interest in and demand for AI technology, combined with a growing AI skills gap, has driven more and more companies toward no-code machine learning solutions. These platforms are revolutionizing the field by making machine learning more accessible to a wider audience, including those without a background in programming or data science.

No-code platforms are designed to enable users to build, train, and deploy machine learning models without writing any code. They typically feature intuitive, visual interfaces where users can manipulate pre-built components and utilize established machine learning algorithms.

These platforms make it possible for users to leverage the predictive power of machine learning to generate insights, make data-driven decisions, and even develop intelligent applications, all without needing to write or understand complex code.

Ethical and Explainable Machine Learning

Another crucial machine learning trend is the increasing focus on ethical and explainable machine learning. As machine learning models become more pervasive, it’s become paramount to understand how they make their decisions and ensure those decisions are made ethically.

Explainable machine learning, often known as interpretable machine learning or explainable AI (XAI), is about developing models that make transparent, understandable predictions. Traditional machine learning models, especially complex ones like deep neural networks, are often seen as “black boxes” because their internal workings are difficult to understand. XAI aims to make the decision-making process of these models understandable to humans.

Alongside explainability, the ethical use of machine learning is gaining increased attention. Ethical machine learning involves ensuring that models are used responsibly, that they are fair, unbiased, and that they respect users’ privacy. It also involves thinking about the potential implications and consequences of these models, including how they could be misused.


Another trend shaping the machine learning landscape is the rising emphasis on machine learning operations, or MLOps. A recent report found that the global MLOps market is predicted to grow from $842 million in 2021 to nearly $13 billion by 2028.

In essence, MLOps is the intersection of machine learning, DevOps, and data engineering, aiming to standardize and streamline the lifecycle of machine learning model development and deployment. The central goal of MLOps is to bridge the gap between the development of machine learning models and their operation in production environments. This involves creating a robust pipeline that enables fast, automated, and reproducible production of models, incorporating steps like data collection, model training, validation, deployment, monitoring, and more.