Jobs at Djinni

Who Are We

We’re Wingplay, a new studio founded by industry veterans from Playtika. Our mission is simple: create great mobile games that players would love to come back to every day. 

The game we are working on right now is a casual gem-themed game from the block puzzle genre. This is our first game, but it definitely won't be our last. Since we’re a small team, every contribution you make will have a big impact and directly shape the player experience. 

What Will You Do

• Read and interpret feature design briefs.
• Design and polish the UI players interact with every day - menus, HUDs, icons, offers, event screens, and more.
• Create 2D art assets and prepare them for smooth handoff to tech artists.
• Help define the visual personality of the game, keeping everything intuitive, cohesive, and polished.
• Collaborate closely with Product managers, Designers, Artists, and Tech artists to make sure the player experience feels seamless and immersive.
• Maintain a consistent visual language across the game.
• Research mobile game visual design trends and apply this knowledge in your designs.
• Iterate quickly, adapt to feedback, and always keep clarity and readability at the core.

Who Are You

• Your portfolio shows strong game UI design - mobile or casual game work is a big plus.
• You bring solid graphic design fundamentals: composition, typography, layout, and color.
• Comfortable preparing and delivering art assets for animation.
• Skilled with Figma, Photoshop, Illustrator (extra credit for Unity or After Effects).
• You enjoy and play games of all kinds - you understand them from a player’s point of view.
• You’ve got illustration skills that help bring icons, assets, and UI elements to life.
• Familiar with using AI tools as part of your creative process.
• A genuine team player - experienced in both giving and receiving feedback constructively.
• You love learning and exploring new things and know how to research the market for inspirations or references.
• You know how to work in a fast-pace environment and meet deadlines.
• Above all, you care about player experience - designing UI and visuals that feel clear, rewarding, and fun.

👉 Ready to make your mark? Send us your portfolio and a short note - we’d love to talk :)

We are looking for a Recruiter (Screening Specialist) to join our growing team. Your primary responsibility will be to conduct screening interviews with candidates, following a structured list of questions we provide. You will also handle written communication with candidates and ensure smooth coordination throughout the early stages of the hiring process.

Responsibilities

• Conduct initial screening calls with candidates in English (using provided scripts and guidelines).
• Ask predefined questions and record candidate responses.
• Answer candidates’ basic questions about the company, role, or process.
• Assess communication skills, general fit, and motivation.
• Maintain structured notes and provide feedback to the hiring team.
• Manage ongoing communication with candidates (emails, messages, follow-ups).

Requirements

• English level B2–C1 (clear spoken and written communication).
• Proven experience in IT recruitment (understanding of tech roles, processes, and terminology).
• Strong organizational skills and attention to detail.
• Confident communicator with a professional and friendly approach.
• Ability to work independently while following company guidelines.

Nice to Have

• Experience with ATS/CRM tools (e.g., Lever, Greenhouse, Workable).
• Previous experience in fast-paced startup environments.

What We Offer

• Competitive compensation.
• Remote-first role with flexible working hours.
• Opportunity to work in a growing international tech company.
• Structured process — you won’t need to “sell” roles, just run high-quality screenings and keep communication smooth.

🌍 About Us

We are a fast-growing company in the field of Artificial Intelligence, building cutting-edge solutions for the global tech market. Our work has already been recognized worldwide — we’ve won prestigious accelerators and competitions, including Google for Startups, Techstars, TechCrunch, and NVIDIA Accelerator.

We are expanding rapidly and looking for young, motivated people who want to grow together with us, gain unique experience in the AI industry, and become part of an ambitious international team.

About the Company
We’re building a SaaS platform that solves a critical challenge in industries like HR, PR, AI, and Finance. Our solution has already secured early adopters and paying clients, proving strong product–market fit. We’re now at the scaling stage and looking for an experienced User Acquisition & Growth Expert to help us accelerate.

Our vision is to become a category-defining SaaS with a global footprint. This is a chance to join early, shape the growth playbook from scratch, and directly influence the trajectory of the company.
 

🔑 Key Responsibilities

• Full-funnel growth: Design and execute a scalable user acquisition funnel—from awareness and activation to retention and advocacy.
• Paid media leadership: Launch, manage, and continuously optimize paid channels (Google Ads, Meta, LinkedIn, TikTok, YouTube, etc.), ensuring ROI and sustainable CAC.
• Content & inbound growth: Build SEO and content strategies (blogs, LinkedIn/Medium, thought leadership, video, podcasts, newsletters) that position us as a trusted authority in our space.
• Analytics & attribution: Set up, integrate, and own analytics infrastructure (GA4, Mixpanel, Amplitude, HubSpot reports, cohort analysis, attribution modeling).
• Conversion optimization: Run A/B tests across landing pages, onboarding flows, pricing experiments, and email nurture campaigns.
• Unit economics & growth metrics: Track, optimize, and report on CAC, LTV, churn, retention, ARPU, MRR growth, and payback period.
• Experimentation culture: Launch, track, and analyze rapid growth experiments across both paid and organic channels, scaling winners and cutting losers fast.
• Lifecycle marketing: Build and automate customer journeys (email, in-app, retargeting) to improve activation and retention.
• Team collaboration: Work closely with Product, Sales, and Customer Success teams to ensure alignment across the entire funnel.
• Referral & virality: Design and implement referral/partner programs to expand reach and drive low-CAC growth.

📊 Requirements

• 6–7+ years of proven experience in SaaS growth/marketing (B2B and/or B2C).
• Demonstrated success scaling SaaS products from early traction to hundreds/thousands of customers.
• Expertise in performance marketing, SEO, CRO, and lifecycle marketing.
• Strong proficiency with analytics tools: GA4, Mixpanel, Amplitude, Segment.
• Hands-on experience with CRM & automation platforms (HubSpot, Pipedrive, Zapier, Make).
• Data-driven mindset: confident in building dashboards, analyzing cohorts, and driving decisions from numbers.
• Familiarity with growth frameworks (AARRR funnel, Lean Experimentation, Growth Loops).
• Solid understanding of SaaS metrics: activation, retention, churn, ARPU, MRR, and revenue expansion.
• Excellent communication skills in English (Upper-Intermediate+).
• Bonus: Experience in product-led growth (PLG), international go-to-market strategies, or B2B SaaS enterprise motion.

Country Manager (iGaming)
Remote

We are looking for an experienced Country Manager (iGaming) who will be responsible for driving business growth across several key markets and acting as the company’s main local expert. This is a strategic role requiring strong expertise in product, regulatory aspects, marketing, customer experience, and business analytics. The main task is to define the most effective market entry strategies, scale the client base, and optimize revenues while taking into account local specifics.

Key Responsibilities:

• Develop and implement a business strategy for the assigned market.
• Analyze local regulatory conditions and identify opportunities for safe and effective marketing.
• Identify and leverage cultural, language, and behavioral specifics of users to increase engagement and revenues.
• Adapt product, marketing campaigns, and customer services to the requirements of a specific market.
• Collaborate with cross-functional teams (Marketing, Product, Legal, Support) to ensure end-to-end country management.
• Manage key financial metrics (PnL, revenue, retention, LTV).
• Represent the company at industry events and build partnerships with local stakeholders.

Requirements:

• Proven experience as Country Manager, Regional Manager, or similar role in iGaming / gambling / betting.
• Deep understanding of Tier1 markets (Canada, New Zealand, Western Europe, Nordics).
• Strong expertise in marketing, legal/compliance (gaming licenses), customer service, and operations.
• Strategic mindset combined with a hands-on approach.
• English level: Upper-Intermediate (B2) or higher.
• Strong leadership, communication, and business process management skills.

We Offer:

• 20 vacation days + 36 paid sick leaves per year.
• Flexible schedule with no micromanagement.
• Company-covered training and English classes.
• Opportunity to work towards ambitious goals and see fast results.
• International team with transparent processes.
   

Selection Stages:

1. Call with Recruiter
2. Interview with C-level Marketing Specialist
3. Final Interview with Head of Recruitment
4. Job Offer
   If you are ready to make a positive impact on our product and scale your bold ideas — send us your CV!

Country Manager (iGaming)
Remote

We are looking for an experienced Country Manager (iGaming) who will be responsible for driving business growth across several key markets and acting as the company’s main local expert. This is a strategic role requiring strong expertise in product, regulatory aspects, marketing, customer experience, and business analytics. The main task is to define the most effective market entry strategies, scale the client base, and optimize revenues while taking into account local specifics.

Key Responsibilities:

Develop and implement a business strategy for the assigned market.

Analyze local regulatory conditions and identify opportunities for safe and effective marketing.

Identify and leverage cultural, language, and behavioral specifics of users to increase engagement and revenues.

Adapt product, marketing campaigns, and customer services to the requirements of a specific market.

Collaborate with cross-functional teams (Marketing, Product, Legal, Support) to ensure end-to-end country management.

Manage key financial metrics (PnL, revenue, retention, LTV).

Represent the company at industry events and build partnerships with local stakeholders.

Requirements:

Proven experience as Country Manager, Regional Manager, or similar role in iGaming / gambling / betting.

Deep understanding of Tier1 markets (Canada, New Zealand, Western Europe, Nordics).

Strong expertise in marketing, legal/compliance (gaming licenses), customer service, and operations.

Strategic mindset combined with a hands-on approach.

English level: Upper-Intermediate (B2) or higher.

Strong leadership, communication, and business process management skills.

We Offer:

20 vacation days + 36 paid sick leaves per year.

Flexible schedule with no micromanagement.

Company-covered training and English classes.

Opportunity to work towards ambitious goals and see fast results.

International team with transparent processes.
 

Selection Stages:

Call with Recruiter

Interview with C-level Marketing Specialist

Final Interview with Head of Recruitment

Job Offer
If you are ready to make a positive impact on our product and scale your bold ideas — send us your CV!

Support Manager in the Travel Industry

We are looking for a responsible and energetic individual to join our team as a Support Manager in the travel industry. The main task of this position is to provide prompt and high-quality support to our clients, hotels, and partners.

Responsibilities:

1. Responding to client inquiries via email and phone calls within established timeframes.

2. Understanding and promptly resolving booking issues.

3. Ensuring effective communication with hotels, partners, and other stakeholders.

4. Understanding the specifics of the travel industry and having travel experience are advantages.

Requirements:

• Experience in support or client service in the travel industry.
• High responsibility.
• Flexibility and readiness to work on weekends.
• Ability to work efficiently with computers.
• Work schedule from 6 a.m. to 3 p.m. (Kyiv time), mandatory at the computer, 7 days a week.

Role
 

As a Quant Developer you will be building our market making systems from the ground up — quoting engine, order management, execution, risk. You will work closely with our researcher and trader to turn models into production strategies. This role is central to establishing our market making infrastructure and directly drives trading results.

Responsibilities
 

- Develop and maintain market making engine

- Build and optimize connectivity to exchange APIs (OKX, Binance, Bybit)

- Ensure low-latency, reliable execution (Rust, async)

- Implement risk controls and monitoring

- Work with researchers to productionize signals

Requirements
 

- Strong skills in Rust (C++/Go acceptable)

- 3+ years of experience in building real-time / low-latency / high-throughput systems

- Knowledge of concurrency, async/await, memory management

- Familiarity with order books, trading infra is a plus

Perks
 

- Direct impact on production systems and PnL

- Performance-based bonus linked to firm’s trading profit

- Small, high-ownership team

- Remote-first

QATestLab is an international provider of independent testing services with 20+ years of experience delivering QA support across multiple industries — from eCommerce, banking, and healthcare to gaming, media, and telecom. Our service portfolio includes manual testing and test automation services for web, desktop, mobile, and cloud applications.

We are looking for an Intern QA Engineer (Game) to join our friendly team and work from the office!
 

If you completed testing courses, and have English at the Intermediate+ level — don’t waste a minute: send your CV and become part of QATestLab!
 

We expect that you:

• Have basic theoretical and practical training in software testing (testing courses, etc.)
• Have a strong Intermediate+ level of English to communicate effectively with clients and colleagues
• Are an advanced mobile devices user
• Understand the role and importance of software tester’s work in quality software creation
• Attentive to details, inquisitive, meticulous, and ready to learn non-stop
• Aspire to explore bugs in real and interesting projects
• Passionate about games and understand what quality gameplay looks like from a user’s perspective.
   

Main responsibilities:

• Test games and mobile applications
• Report bugs in the bug tracking system
• Create test cases
• Write reports about testing results
• Participate in MS Teams meetings with your team
   

We offer:

• Flexible working hours: starting from 8 to 11 AM; full-time
• Possibility to work remotely
• Decent compensation with regular reviews based on the results
• 100% reimbursement with sick leave letter, 18 days off
• Mentor support at the beginning
• Free English and QA courses
• Developed corporate culture, loyalty, and assistance programs
   

Send your resume and become part of QATestLab!

We’re looking for a motivated Junior Project Manager to join our team and help to coordinate our projects.
 

Responsibilities

• Assist in planning and coordinating web development projects to ensure they are completed on time and meet quality standards.
• Support the senior project manager in defining project scope, goals, and deliverables.
• Monitor daily tasks, track progress and ensure team members meet deadlines.
• Communicate with clients under the guidance of senior staff: address basic inquiries and provide updates on project status.
• Prepare and maintain project documentation, meeting notes, and reports.
• Help identify risks and contribute to solutions to keep projects on track.

Requirements

• Strong organisational and multitasking skills with attention to detail.
• Excellent communication and interpersonal abilities.
• Basic understanding of project management tools (e.g., Jira, Trello, Asana) or a willingness to learn.
• Familiarity with web development concepts is a plus, but not required.
• A proactive and adaptable attitude with a desire to grow professionally.
• Ability to work collaboratively in a distributed team.

Nice to Have

• Previous internship or experience in project coordination or a related field.
• Upper-intermediate level of English; Polish language skills would be an advantage.

What We Offer

• Competitive salary paid in euros and regular, on-time payments.
• Flexible working hours and 100 % remote work — you control your schedule.
• Mentorship, training and clear opportunities for career growth: we’ll help you advance to middle and senior PM levels.
• A friendly, supportive team with minimal bureaucracy and transparent areas of responsibility.
• Participation in international projects with real impact and the chance to develop alongside our team.

We are seeking a Middle Flutter Developer to join our team and contribute to the development of modern, cross-platform mobile applications. You will collaborate with product managers, designers and developers to deliver user-friendly, reliable and scalable apps.

Responsibilities

• Develop and maintain Flutter mobile applications.
• Implement new features, fix bugs and improve performance.
• Collaborate with designers and backend developers to deliver complete solutions.
• Write clean, maintainable code and participate in code reviews.
• Contribute to the continuous improvement of our processes and products.

Requirements

• 2–3+ years of commercial Flutter/Dart experience.
• Experience with state management (BLoC, Provider, Riverpod or similar).
• Hands-on experience with API integration and app navigation.
• Good understanding of Git, testing and agile workflows.
• Strong communication skills in English and the ability to work remotely in a team.

Nice to Have

• Knowledge of native iOS/Android development (Swift/Kotlin).
• Experience with GraphQL, WebSockets or offline data storage.
• Contributions to open source or a strong GitHub portfolio.

What We Offer

• Competitive compensation in USD/EUR with flexible payment terms.
• 100% remote work and flexible schedule.
• International projects with real impact.
• Supportive and collaborative team culture.
• Clear opportunities for growth and professional development.

If you are passionate about Flutter development and want to grow in a friendly, international environment, we’d love to hear from you!

Growth Automation is a Business Development & Lead Generation AI firm serving B2B companies worldwide. We’re building a team of A-players to help us positively impact the B2B business world.

We are building a team of A-players to join us on the journey to make a positive impact in the B2B business world.

That’s why we’re looking for a Billing & Invoicing Coordinator to join our team.

The Role:

The Billing & Invoicing Coordinator will be responsible for ensuring that our invoicing process runs smoothly and efficiently. This role is hourly, freelance, and part-time — only a few hours each week but requiring you to check in several times weekly.

Key responsibilities include:

• Creating and updating invoices for clients in Xero
• Monitoring outstanding balances and preparing summaries for the management team
• Communicating with clients regarding overdue payments (via email and phone)
• Following up consistently on delayed invoices and handling collections agencies when needed
• Staying organized and maintaining accurate records of invoicing activities
• Handling additional invoicing-related tasks as required
   

This role does not involve bookkeeping or accounting. It is an entry-level opportunity that does not require extensive prior experience — but strong organization, professionalism, and attention to detail are a must.
 

Requirements

• Experience using Xero invoicing (essential)
• Fluent in English (spoken and written)
• Comfortable making client calls regarding payment follow-up
• Very organized, detail-oriented, and proactive
• Reliable and able to sign in multiple times per week
• Previous invoicing or billing experience is a plus, but not strictly required
   

Hours & Compensation

• Freelance, part-time (a few hours per week, flexible schedule)
• Hourly pay, based on experience
• Remote role — work from anywhere
• Opportunity to grow with the company and take on more responsibility over time

We are looking for a macOS engineer with 3 years of experience to join a small team developing an innovative productivity tool for macOS. 

This is an exciting opportunity to build a high-quality product from the ground up. 

What You’ll Do: 

Research & Development Phase: 

• Work on a Proof of Concept to validate the feasibility of the solution.

Development & Implementation Phase:

• Work hands-on with Swift and macOS frameworks to build a production-ready product. 
• Collaborate closely with a small engineering team, including another developer leading the project. 
• Maintain high standards and ensure clean, maintainable code. 
• Work in close collaboration with UX/UI designer, PO, QA, and PM to refine and deliver the best user experience. 

Requirements:

•  You have 3 years of experience in software development, with a strong background in Swift and macOS development. 
• You can analyze and integrate open-source components to build a robust product. 
• You write clean, efficient, and scalable code while maintaining a strong focus on usability. 
• Experience with unit testing, debugging, and performance optimization. 
• You enjoy collaborating with teammates to build intuitive, high-quality applications.

About us:
Data Science UA is a service company with strong data science and AI expertise. Our journey began in 2016 with uniting top AI talents and organizing the first Data Science tech conference in Kyiv. Over the past 9 years, we have diligently fostered one of the largest Data Science & AI communities in Europe.

About the client:
Our client is an IT company that develops technological solutions and products to help companies reach their full potential and meet the needs of their users. The team comprises over 600 specialists in IT and Digital, with solid expertise in various technology stacks necessary for creating complex solutions.

About the role:
We are looking for an experienced Senior/Middle Data Scientist with a passion for Large Language Models (LLMs) and cutting-edge AI research. In this role, you will focus on designing and prototyping data preparation pipelines, collaborating closely with data engineers to transform your prototypes into scalable production pipelines, and actively developing model training pipelines with other talented data scientists. Your work will directly shape the quality and capabilities of the models by ensuring we feed them the highest-quality, most relevant data possible.

Requirements:
Education & Experience:
- 3+ years of experience in Data Science or Machine Learning, preferably with a focus on NLP.
- Proven experience in data preprocessing, cleaning, and feature engineering for large-scale datasets of unstructured data (text, code, documents, etc.).
- Advanced degree (Master’s or PhD) in Computer Science, Computational Linguistics, Machine Learning, or a related field is highly preferred.
NLP Expertise:
- Good knowledge of natural language processing techniques and algorithms.
- Hands-on experience with modern NLP approaches, including embedding models, semantic search, text classification, sequence tagging (NER), transformers/LLMs, RAGs.
- Familiarity with LLM training and fine-tuning techniques.
ML & Programming Skills:
- Proficiency in Python and common data science and NLP libraries (pandas, NumPy, scikit-learn, spaCy, NLTK, langdetect, fasttext).
- Strong experience with deep learning frameworks such as PyTorch or TensorFlow for building NLP models.
- Ability to write efficient, clean code and debug complex model issues.
Data & Analytics:
- Solid understanding of data analytics and statistics.
- Experience in experimental design, A/B testing, and statistical hypothesis testing to evaluate model performance.
- Comfortable working with large datasets, writing complex SQL queries, and using data visualization to inform decisions.
Deployment & Tools:
- Experience deploying machine learning models in production (e.g., using REST APIs or batch pipelines) and integrating with real-world applications.
- Familiarity with MLOps concepts and tools (version control for models/data, CI/CD for ML).
- Experience with cloud platforms (AWS, GCP, or Azure) and big data technologies (Spark, Hadoop, Ray, Dask) for scaling data processing or model training.
Communication & Personality:
- Experience working in a collaborative, cross-functional environment.
- Strong communication skills to convey complex ML results to non-technical stakeholders and to document methodologies clearly.
- Ability to rapidly prototype and iterate on ideas

Nice to have:
Advanced NLP/ML Techniques:
- Familiarity with evaluation metrics for language models (perplexity, BLEU, ROUGE, etc.) and with techniques for model optimization (quantization, knowledge distillation) to improve efficiency.
- Understanding of FineWeb2 or similar processing pipelines approach.
Research & Community:
- Publications in NLP/ML conferences or contributions to open-source NLP projects.
- Active participation in the AI community or demonstrated continuous learning (e.g., Kaggle competitions, research collaborations) indicating a passion for staying at the forefront of the field.
Domain & Language Knowledge:
- Familiarity with the Ukrainian language and context.
- Understanding of cultural and linguistic nuances that could inform model training and evaluation in a Ukrainian context.
- Knowledge of Ukrainian text sources and data sets, or experience with multilingual data processing, can be an advantage given the project’s focus.
MLOps & Infrastructure:
- Hands-on experience with containerization (Docker) and orchestration (Kubernetes) for ML, as well as ML workflow tools (MLflow, Airflow).
- Experience in working alongside MLOps engineers to streamline the deployment and monitoring of NLP models.
Problem-Solving:
- Innovative mindset with the ability to approach open-ended AI problems creatively.
- Comfort in a fast-paced R&D environment where you can adapt to new challenges, propose solutions, and drive them to implementation.

Responsibilities:
- Design, prototype, and validate data preparation and transformation steps for LLM training datasets, including cleaning and normalization of text, filtering of toxic content, de-duplication, de-noising, detection and deletion of personal data, etc.
- Formation of specific SFT/RLHF datasets from existing data, including data augmentation/labeling with LLM as teacher.
- Analyze large-scale raw text, code, and multimodal data sources for quality, coverage, and relevance.
- Develop heuristics, filtering rules, and cleaning techniques to maximize training data effectiveness.
- Collaborate with data engineers to hand over prototypes for automation and scaling.
- Research and develop best practices and novel techniques in LLM training pipelines.
- Monitor and evaluate data quality impact on model performance through experiments and benchmarks.
- Research and implement best practices in large-scale dataset creation for AI/ML models.
- Document methodologies and share insights with internal teams.

The company offers:
- Competitive salary.
- Equity options in a fast-growing AI company.
- Remote-friendly work culture.
- Opportunity to shape a product at the intersection of AI and human productivity.
- Work with a passionate, senior team building cutting-edge tech for real-world business use.

About us:
Data Science UA is a service company with strong data science and AI expertise. Our journey began in 2016 with uniting top AI talents and organizing the first Data Science tech conference in Kyiv. Over the past 9 years, we have diligently fostered one of the largest Data Science & AI communities in Europe.

About the client:
Our client is an IT company that develops technological solutions and products to help companies reach their full potential and meet the needs of their users. The team comprises over 600 specialists in IT and Digital, with solid expertise in various technology stacks necessary for creating complex solutions.

About the role:
We are looking for a Data Engineer (NLP-Focused) to build and optimize the data pipelines that fuel the Ukrainian LLM and NLP initiatives. In this role, you will design robust ETL/ELT processes to collect, process, and manage large-scale text and metadata, enabling the Data Scientists and ML Engineers to develop cutting-edge language models.

You will work at the intersection of data engineering and machine learning, ensuring that the datasets and infrastructure are reliable, scalable, and tailored to the needs of training and evaluating NLP models in a Ukrainian language context.

Requirements:
- Education & Experience: 3+ years of experience as a Data Engineer or in a similar role, building data-intensive pipelines or platforms. A Bachelor’s or Master’s degree in Computer Science, Engineering, or a related field is preferred. Experience supporting machine learning or analytics teams with data pipelines is a strong advantage.
- NLP Domain Experience: Prior experience handling linguistic data or supporting NLP projects (e.g., text normalization, handling different encodings, tokenization strategies). Knowledge of Ukrainian text sources and data sets, or experience with multilingual data processing, can be an advantage given the project’s focus.
Understanding of FineWeb2 or a similar processing pipeline approach.
- Data Pipeline Expertise: Hands-on experience designing ETL/ELT processes, including extracting data from various sources, using transformation tools, and loading into storage systems. Proficiency with orchestration frameworks like Apache Airflow for scheduling workflows. Familiarity with building pipelines for unstructured data (text, logs) as well as structured data.
- Programming & Scripting: Strong programming skills in Python for data manipulation and pipeline development. Experience with NLP packages (spaCy, NLTK, langdetect, fasttext, etc.). Experience with SQL for querying and transforming data in relational databases. Knowledge of Bash or other scripting for automation tasks. Writing clean, maintainable code and using version control (Git) for collaborative development.
- Databases & Storage: Experience working with relational databases (e.g., PostgreSQL, MySQL), including schema design and query optimization. Familiarity with NoSQL or document stores (e.g., MongoDB) and big data technologies (HDFS, Hive, Spark) for large-scale data is a plus. Understanding of or experience with vector databases (e.g., Pinecone, FAISS) is beneficial, as the NLP applications may require embedding storage and fast similarity search.
- Cloud Infrastructure: Practical experience with cloud platforms (AWS, GCP, or Azure) for data storage and processing. Ability to set up services such as S3/Cloud Storage, data warehouses (e.g., BigQuery, Redshift), and use cloud-based ETL tools or serverless functions. Understanding of infrastructure-as-code (Terraform, CloudFormation) to manage resources is a plus.
- Data Quality & Monitoring: Knowledge of data quality assurance practices. Experience implementing monitoring for data pipelines (logs, alerts) and using CI/CD tools to automate pipeline deployment and testing. An analytical mindset to troubleshoot data discrepancies and optimize performance bottlenecks.
- Collaboration & Domain Knowledge: Ability to work closely with data scientists and understand the requirements of machine learning projects. Basic understanding of NLP concepts and the data needs for training language models, so you can anticipate and accommodate the specific forms of text data and preprocessing they require. Good communication skills to document data workflows and to coordinate with team members across different functions.

Responsibilities:
- Design, develop, and maintain ETL/ELT pipelines for gathering, transforming, and storing large volumes of text data and related information.
- Ensure pipelines are efficient and can handle data from diverse sources (e.g., web crawls, public datasets, internal databases) while maintaining data integrity.
- Implement web scraping and data collection services to automate the ingestion of text and linguistic data from the web and other external sources. This includes writing crawlers or using APIs to continuously collect data relevant to the language modeling efforts.
- Implementation of NLP/LLM-specific data processing: cleaning and normalization of text, like filtering of toxic content, de-duplication, de-noising, detection, and deletion of personal data.
- Formation of specific SFT/RLHF datasets from existing data, including data augmentation/labeling with LLM as teacher.
- Set up and manage cloud-based data infrastructure for the project. Configure and maintain data storage solutions (data lakes, warehouses) and processing frameworks (e.g., distributed compute on AWS/GCP/Azure) that can scale with growing data needs.
- Automate data processing workflows and ensure their scalability and reliability.
- Use workflow orchestration tools like Apache Airflow to schedule and monitor data pipelines, enabling continuous and repeatable model training and evaluation cycles.
- Maintain and optimize analytical databases and data access layers for both ad-hoc analysis and model training needs.
- Work with relational databases (e.g., PostgreSQL) and other storage systems to ensure fast query performance and well-structured data schemas.
- Collaborate with Data Scientists and NLP Engineers to build data features and datasets for machine learning models.
- Provide data subsets, aggregations, or preprocessing as needed for tasks such as language model training, embedding generation, and evaluation.
- Implement data quality checks, monitoring, and alerting. Develop scripts or use tools to validate data completeness and correctness (e.g., ensuring no critical data gaps or anomalies in the text corpora), and promptly address any pipeline failures or data issues. Implement data version control.
- Manage data security, access, and compliance.
- Control permissions to datasets and ensure adherence to data privacy policies and security standards, especially when dealing with user data or proprietary text sources.

The company offers:
- Competitive salary.
- Equity options in a fast-growing AI company.
- Remote-friendly work culture.
- Opportunity to shape a product at the intersection of AI and human productivity.
- Work with a passionate, senior team building cutting-edge tech for real-world business use.

About us:
Data Science UA is a service company with strong data science and AI expertise. Our journey began in 2016 with uniting top AI talents and organizing the first Data Science tech conference in Kyiv. Over the past 9 years, we have diligently fostered one of the largest Data Science & AI communities in Europe.

About the client:
Our client is an IT company that develops technological solutions and products to help companies reach their full potential and meet the needs of their users. The team comprises over 600 specialists in IT and Digital, with solid expertise in various technology stacks necessary for creating complex solutions.

About the role:
We are looking for an experienced Senior/Middle Data Scientist with a passion for Large Language Models (LLMs) and cutting-edge AI research. In this role, you will focus on designing and prototyping data preparation pipelines, collaborating closely with data engineers to transform your prototypes into scalable production pipelines, and actively developing model training pipelines with other talented data scientists. Your work will directly shape the quality and capabilities of the models by ensuring we feed them the highest-quality, most relevant data possible.

Requirements:
Education & Experience:
- 3+ years of experience in Data Science or Machine Learning, preferably with a focus on NLP.
- Proven experience in data preprocessing, cleaning, and feature engineering for large-scale datasets of unstructured data (text, code, documents, etc.).
- Advanced degree (Master’s or PhD) in Computer Science, Computational Linguistics, Machine Learning, or a related field is highly preferred.
NLP Expertise:
- Good knowledge of natural language processing techniques and algorithms.
- Hands-on experience with modern NLP approaches, including embedding models, semantic search, text classification, sequence tagging (NER), transformers/LLMs, RAGs.
- Familiarity with LLM training and fine-tuning techniques.
ML & Programming Skills:
- Proficiency in Python and common data science and NLP libraries (pandas, NumPy, scikit-learn, spaCy, NLTK, langdetect, fasttext).
- Strong experience with deep learning frameworks such as PyTorch or TensorFlow for building NLP models.
- Ability to write efficient, clean code and debug complex model issues.
Data & Analytics:
- Solid understanding of data analytics and statistics.
- Experience in experimental design, A/B testing, and statistical hypothesis testing to evaluate model performance.
- Comfortable working with large datasets, writing complex SQL queries, and using data visualization to inform decisions.
Deployment & Tools:
- Experience deploying machine learning models in production (e.g., using REST APIs or batch pipelines) and integrating with real-world applications.
- Familiarity with MLOps concepts and tools (version control for models/data, CI/CD for ML).
- Experience with cloud platforms (AWS, GCP, or Azure) and big data technologies (Spark, Hadoop, Ray, Dask) for scaling data processing or model training.
Communication & Personality:
- Experience working in a collaborative, cross-functional environment.
- Strong communication skills to convey complex ML results to non-technical stakeholders and to document methodologies clearly.
- Ability to rapidly prototype and iterate on ideas

Nice to have:
Advanced NLP/ML Techniques:
- Familiarity with evaluation metrics for language models (perplexity, BLEU, ROUGE, etc.) and with techniques for model optimization (quantization, knowledge distillation) to improve efficiency.
- Understanding of FineWeb2 or similar processing pipelines approach.
Research & Community:
- Publications in NLP/ML conferences or contributions to open-source NLP projects.
- Active participation in the AI community or demonstrated continuous learning (e.g., Kaggle competitions, research collaborations) indicating a passion for staying at the forefront of the field.
Domain & Language Knowledge:
- Familiarity with the Ukrainian language and context.
- Understanding of cultural and linguistic nuances that could inform model training and evaluation in a Ukrainian context.
- Knowledge of Ukrainian text sources and data sets, or experience with multilingual data processing, can be an advantage given the project’s focus.
MLOps & Infrastructure:
- Hands-on experience with containerization (Docker) and orchestration (Kubernetes) for ML, as well as ML workflow tools (MLflow, Airflow).
- Experience in working alongside MLOps engineers to streamline the deployment and monitoring of NLP models.
Problem-Solving:
- Innovative mindset with the ability to approach open-ended AI problems creatively.
- Comfort in a fast-paced R&D environment where you can adapt to new challenges, propose solutions, and drive them to implementation.

Responsibilities:
- Design, prototype, and validate data preparation and transformation steps for LLM training datasets, including cleaning and normalization of text, filtering of toxic content, de-duplication, de-noising, detection and deletion of personal data, etc.
- Formation of specific SFT/RLHF datasets from existing data, including data augmentation/labeling with LLM as teacher.
- Analyze large-scale raw text, code, and multimodal data sources for quality, coverage, and relevance.
- Develop heuristics, filtering rules, and cleaning techniques to maximize training data effectiveness.
- Collaborate with data engineers to hand over prototypes for automation and scaling.
- Research and develop best practices and novel techniques in LLM training pipelines.
- Monitor and evaluate data quality impact on model performance through experiments and benchmarks.
- Research and implement best practices in large-scale dataset creation for AI/ML models.
- Document methodologies and share insights with internal teams.

The company offers:
- Competitive salary.
- Equity options in a fast-growing AI company.
- Remote-friendly work culture.
- Opportunity to shape a product at the intersection of AI and human productivity.
- Work with a passionate, senior team building cutting-edge tech for real-world business use.