At AT&T we’re redefining the future of communication by connecting people to greater possibility - with expertise, simplicity, and inspiration. At the heart of our purpose lies a diverse workforce of 140,000 people and a culture that aspires to serve customers first, act boldly, move faster, and win as one.

Our Product Development group, part of AT&T’s Technology Services (ATS) organization, is responsible for building software-based products, services, and platforms that our customers love and need. Harnessing technology and rebuilding software expertise, the team is inspiring simplicity with projects that deliver revenue and cost savings opportunities.

AT&T is building a new era of intelligent automation. We are looking for a Medior Data/AI Engineer who will actively contribute to developing and supporting intelligent systems built around large language models (LLMs), prompt engineering, and data engineering best practices. In this role, you’ll help build, integrate, and maintain AI-powered applications and workflows, working with frameworks like LangGraph, robust data pipelines, and industry-standard tools.

You will be involved in automating workflows using LLMs, Retrieval-Augmented Generation (RAG), and next-gen AI agents. Your work will enable smarter operations, support improved data management, and help deliver adaptive digital services across the organization.

Core Responsibilities

• Assist with designing and optimizing prompts for LLMs across relevant use cases.

• Help implement context management strategies (e.g., session memory, retrieval-augmented generation).

• Support integration and testing of LLMs within Python-based applications using APIs and standard data pipelines.

• Participate in building, testing, and maintaining conversational and agent workflows (e.g., with LangGraph).

• Help maintain backend services, APIs, and data pipelines to ensure reliability and performance.

• Work with product, data science, and engineering teams to gather requirements, test ideas, and iterate on solutions as part of a broader team.

• Contribute to quality assurance efforts: testing, basic monitoring, and evaluation of prompt and workflow effectiveness.

• Apply best practices in code quality, secure/ethical software development, and documentation by learning from peers and seeking feedback.

• Support the implementation of data models and data pipelines, helping ensure data quality and integrity following established procedures.

• Participate in technology evaluations and implementations for scalable and cost-effective solutions under senior supervision.

Skills, Knowledge, and Experience

Day-to-Day:

• Help build and support AI agent solutions and automation workflows using LLMs, prompt engineering, and context management.

• Collaborate with team members to understand requirements and support prompt experiments and solution development.

• Assist with development and maintenance of Python applications and data workflows for AI agent deployment.

• Engage in code reviews, knowledge sharing, and adhere to technical best practices established by the team.

• Participate in monitoring and evaluation to improve workflow quality.

Technical Skills:

• Experience with Python development (FastAPI, Flask; SQL/NoSQL databases).

• Experience with prompt engineering for LLMs (e.g., OpenAI, Anthropic, open source).

• Good understanding of context management concepts (session management, vector search, retrieval).

• Hands-on experience with agentic/conversational flow frameworks such as LangGraph.

• Experience with Retrieval-Augmented Generation (RAG) and multi-agent workflow concepts.

• Familiarity with cloud environments and basic containerization (Docker) is a plus.

• Willingness to learn and apply modern API development and microservice patterns (REST, GraphQL).

• Exposure to data engineering tools/technologies (e.g., Spark, Kafka, Databricks, Snowflake) and SQL/another relevant language a plus.

• Experience with AI-powered IDEs and tools (e.g., Visual Studio, GitHub Copilot, Windsurf, Cursor).

• Interest in, or basic exposure to, fine-tuning language models is a PLUS.

Additional Experience in (Hard-Core Data Science + LLM/GenAI Data Science Experience) as a Plus:

• Interest in developing knowledge of statistics, machine learning (probability, hypothesis testing, experimentation, regularization), and their practical applications in business/AI contexts.

• Experience supporting or learning about predictive model building and validation (e.g., feature engineering, model training, error analysis) using tools like scikit-learn or XGBoost/other ML libraries.

• Willingness to assist with experiments and contribute to evaluation (offline metrics, basic A/B testing, quality monitoring) under senior guidance.

• Awareness or interest in LLM evaluation strategies (including automated/human-in-the-loop, task quality, safety metrics).

• Some understanding or curiosity about RAG-focused data science, prompt optimization, and LLM troubleshooting.

• Desire to develop hands-on skills with prompt optimization, adaptation techniques (LoRA/QLoRA, DPO/IPO), data labeling, and evaluation approaches.

• Familiarity with basic system performance considerations for LLMs (token optimization, latency, model routing) is a plus.

• Openness to learning about interpretability and debugging practices for GenAI/AI systems.

Education: 

Bachelor level degree or equivalent in Computer Science, or related field of study. 

Compensation:

Salary range for Slovakia is between 3 283EUR - 4 933EUR gross per month.

Salary range for Czech Republic is between94 633CZK - 141 941CZK gross per month.

The individual starting salary within this range will depend on relevant factors such as the candidate’s experience, expertise, skills, and education or training.

Benefits: 

A career with us, a global leader in communications and technology, comes with big rewards. We offer a competitive salary plus an annual company performance bonus. Once you’re a part of the team, you’ll gain some amazing perks and benefits including wellness & leisure time contribution, sickness compensation plan, premium medical services, family friendly benefits as well as meal contribution and extra days of vacation (…and much more). 

Location: 

This is a hybrid-flex worker position where our preference is for you to be present with your team in the office at least 2 days per week.   

Ready to find out more? Apply today!   

Weekly Hours:

40

Time Type:

Regular

Location:

Bratislava, Slovakia, CZE:642:Brno / Palachovo Namesti 726/4 Block A&b - Adm:2 Palachovo Namesti

It is the policy of AT&T to provide equal employment opportunity (EEO) to all persons regardless of age, color, national origin, citizenship status, physical or mental disability, race, religion, creed, gender, sex, sexual orientation, gender identity and/or expression, genetic information, marital status, status with regard to public assistance, veteran status, or any other characteristic protected by federal, state or local law. In addition, AT&T will provide reasonable accommodations for qualified individuals with disabilities. AT&T is a fair chance employer and does not initiate a background check until an offer is made.

Job ID R-115717 Date posted 07/14/2026