Machine Learning Engineer

Job description

Cosmose is a fast-growing software company on a path to revolutionize the $600BN advertising industry. Its OMNIcookie, a cookie for the physical world, reaches over 1 billion smartphones in Asia. Cosmose delivers results for the world’s biggest luxury and cosmetics brands, including L'Oreal, LVMH and Cartier.

Since 2014, Cosmose has grown to 1B smartphones, 350K stores, 3 offices, 2m accuracy, 1 AI brain and 50+ world's best talents. We’re proud of our achievements and growth, but... we haven't even started yet.

Joining us - means working with strong, smart and innovative team located in our Warsaw R&D Center. We ask hard questions and challenge each other to constantly improve our work.

Learn more about us:

Currently, we are looking for an expert in machine learning to help us extract value from our data and create artificial intelligence products. You'll be part of a growing team, crafting our infrastructure and delivering value to our customers.


  • Understanding business objectives and developing models that help to achieve them, along with metrics to track their progres
  • Managing available resources such as hardware, data, and personnel so that deadlines are met
  • Analyzing the ML algorithms that could be used to solve a given problem and ranking them by their success probability
  • Exploring and visualizing data to gain an understanding of it, then identifying differences in data distribution that could affect performance when deploying the model in the real world
  • Verifying data quality, and/or ensuring it via data cleaning
  • Supervising the data acquisition process if more data is needed
  • Finding available datasets online that could be used for training
  • Defining validation strategies
  • Defining the preprocessing or feature engineering to be done on a given dataset
  • Defining data augmentation pipelines
  • Training models and tuning their hyperparameters
  • Analyzing the errors of the model and designing strategies to overcome them
  • Deploying models to production
  • Teaching and mentoring others in the use of AI/Machine Learning


  • Proficiency with Python, SQL, RESTful API and libraries such as Pandas, SciPy, NumPy, Scikit-Learn, Matplotlib
  • Familiarity with Jupyter Notebook
  • Proficiency with a deep learning framework such as TensorFlow, Keras, Pytorch
  • Practical knowledge of Linux OS (Ubuntu)
  • Demonstrated ability in the application of Machine Learning in real-world industrial settings with large scale data
  • Hands-on working experience with ML models for time series forecasting
  • Knowledge of core CS concepts such as: common data structures and algorithms
  • Proactive attitude - we hire people that have a strong desire to do better and be better
  • Outstanding analytical and problem-solving skills
  • BSc in Engineering, Physics, Mathematics, Statistics, Computer Science, Data Science or similar field
  • B2 Level in English
  • Experience working with agile software development methodologies (scrum)

Bonus points for:

  • Mathematical background (linear algebra/statistics/optimization methods)
  • Familiarity with Amazon Web Services (AWS), Kubernetes, Docker
  • Familiarity with a data processing frameworks (e.g. Spark, Dask)
  • Experience with Machine Learning models for recommendation engine, time series forecasting and digital signal processing

What you can expect from us:

  • (80-120 PLN net per hour) B2B or regular employment contract (13 000 - 20 000 PLN gross per month)
  • English and Chinese lessons for free
  • Referral bonuses
  • Friendly working atmosphere: flexible working hours, ability to work remotely a couple days each month, beautiful office in Warsaw prime city center (Check it!), bike parking, equipment of your choice, standing desk and anything you need to survive in the office :) (xbox, great coffee and popcorn)
  • Small impactful teams of experienced people and opportunity to work in multiple projects
  • Working in a product company that has gained great success in Asia