Home | Careers | Jobs

Junior AI Research Engineer

Location icon | Phrase

Czech Republic

AI Researcher

At Phrase, we help open the door to global business by providing the world’s leading Language Intelligence Platform.

The Phrase Platform combines AI, agentic orchestration, and a headless, API-first architecture in one composable system. Beyond translation, it orchestrates and adapts content to culture, audience, channel, brand voice, and intended outcome in any language, for every audience. It applies the context that makes content perform in every market: quality standards, glossaries, prior translations, and cultural nuance. Every team, in every region, can ship content that is on-brand, on-point, and ready for any audience.

Phrase gives enterprises the intelligence to automate workflows, the freedom to connect their own tools and engines, and the control to govern global content at scale.

With a global team based in our offices, and remote colleagues across Europe, the UK, the US, and the APAC region, Phrase offers an international environment built on collaboration, innovation, and shared purpose.

Phrase’s AI Research team builds and evaluates the proprietary translation models and agentic workflows that power the platform’s language quality — live systems serving production traffic, not proof-of-concept work. This role sits inside that team as a hands-on contributor, running experiments, fine-tuning models, and building evaluation pipelines alongside senior researchers. You’ll work across fine-tuning LLMs for domain-specific machine translation, multi-agent evaluation pipelines, automated quality profiling from style guides, and active learning through feedback loops on real customer data. It’s built for someone earlier in their research career with strong fundamentals who wants to grow their depth in applied NLP and machine translation inside a team that ships research into production.

What you’ll be responsible for:

• Fine-tune and evaluate LLMs for translation and language-quality tasks, applying techniques such as LoRA, with support from senior researchers.

• Build evaluation pipelines for translation quality, applying automatic metrics (BLEU, TER, ChrF, MQM, COMET) and LLM-as-judge approaches, and contribute to their design.

• Build and evaluate agentic workflows spanning multi-step reasoning, tool use, and structured output generation.

• Implement and evaluate components within the team’s model-development programme, working to a defined scope.

• Run reproducible experiments and document results and decisions clearly.

• Work with Product, Engineering, and Solutions to turn research into shippable capabilities.

• Benchmark frontier and open-source models against internal baselines.

• Support the evolution of quality-evaluation systems, including style-guide integration.

• Support data-pipeline and feedback-loop work for continuous model improvement.

• Take part in reading groups, deep dives, and code and research reviews.

• Share results early and build on the team’s existing work.

• Contribute to hiring tasks as you grow into the role.

What you need:

• Solid grounding in machine learning and NLP, with hands-on experience fine-tuning or working with LLMs or transformer-based models.

• Working knowledge of at least one relevant area: machine translation, MT evaluation, information extraction, text generation, or search.

• Exposure to, or strong interest in, agentic or LLM-orchestrated systems (ability to build them from first principles is desirable, not required).

• Experience running experiments and applying evaluation metrics, with awareness of both automatic and human-in-the-loop evaluation.

• Solid Python skills and experience with ML/NLP libraries such as Hugging Face or PyTorch.

• MSc in Computer Science, Computational Linguistics, or a related field, or a BSc with relevant experience, projects, or a strong portfolio.

• A PhD is welcome but not required (desirable).

• Internships, thesis work, or projects in NLP/MT, ideally with production or applied exposure (desirable).

• Familiarity with localization or MT concepts such as MQM, COMET, post-editing, or TMS integrations (desirable).

• Exposure to experiment tracking tools such as Weights & Biases, or agentic-pipeline frameworks such as PydanticAI or LangGraph (desirable).

• Publications or open-source contributions in NLP-related topics (desirable).

• Curious and coachable, with a habit of asking good questions and acting on feedback.

• Comfortable sharing results early, inviting challenge, and building on others’ work.

Our current tech stack in this role:

• Python

• Hugging Face

• PyTorch

• Weights & Biases

• PydanticAI

• LangGraph

What you’ll get:

– Work experience in a successful and growing global SaaS company

– Be part of an international team in Europe, APAC, and the Americas

– Expert colleagues in their field who are determined to build the best localization platform on the market, creating a world where language never limits opportunity

– An agile work environment, where it is encouraged to take smart risks

– Take part in a culture full of trust, support and loyalty, where respectful and open feedback is valued, and diversity is fully embraced

– A positive, open-minded, and innovative atmosphere

– Support in your professional development and personal career goals

What’s on top:

– 4 Company holidays additional to your regular holidays (1 day per quarter where the entire company is off to celebrate our achievements).

– In addition, the company also provides employees with a Christmas break to allow you to spend time with family and friends without use of your vacation allocation.

– Your birthday is off because it is important to celebrate you as well.

– 2 Giveback days where you can support the local community, volunteer, and/or participate in charity events and activities.

– Professional and extensive onboarding.

– Enterprise Claude Licence

– Additional local benefits depending on the entity you’re hired at, just ask your Talent Acquisition Partner

Phrase is committed to ensuring equal pay for equal work and work of equal value between women and men. Our aim is that our workforce will be truly representative of all sections of society and that each worker feels respected and able to give their best. The job requirements and salary range for this job have been established through a gender-neutral job evaluation and classification process. This process objectively assesses the skills, responsibility, effort and working conditions required for each job. This systematic approach ensures fair pay regardless of who performs the work. We welcome applications from all qualified candidates regardless of their sex, race or ethnicity, disability, religion/belief, sexual orientation, gender identity or age. We value and welcome different perspectives, experiences and backgrounds as we believe that these differences make our team even stronger on our mission of opening the door to global business by giving everybody access to the content they need in the language they speak.

Our application process

Get in touch

Submit your application through the job ad.

How to make your application stand out:

  • We encourage you to share your pronouns with us so we know how to correctly approach you.
  • Closely read our job descriptions and apply for the one(s) that best align with your experience.
  • Share why you are interested in joining our team and if our mission resonates with you.
  • Make sure we have everything we need to know: your qualifications, strengths, and ambitions. This may be in form of your CV/ resume, cover letters, portfolios, websites, or work samples.
  • Give us your latest contact details.
  • Please apply in English. We’re an international business, but our company language is English. This way we can ensure that everyone involved fully understands what you bring to the table.

Talk with us

If your experience suits our needs, we’ll reach out to get to know you.

Firstly, someone from our talent acquisition team will contact you to schedule a video call to learn more about you and your experience. At the same time, you’ll learn more about our business, the team, and the role you’re interviewing for.

The next stages vary slightly depending on the team you apply for and the seniority level of the role, but it will look something like this:

  • You’ll meet the manager you’ll report to.
  • There will be some kind of skill assessment, such as a coding or design task, a role play, or a business case.
  • You’ll meet some of the main stakeholders and team members. Your talent acquisition partner will guide you all the way through, keep you updated, tell you who you’re going to meet next, and where you’re standing.

Some things to consider:

  • Our entire interview process is virtual. We work with Google Meet and Zoom.
  • We assess your skill set, but we’re also interested in seeing if your values and goals align with ours.

Secure the job

Once we know you and you know us, it’s time for all of us to make a decision.

  • We aim to make hiring decisions within a couple of days. This can be delayed if we have several people interviewing for the same role, but we’ll keep you updated. We hope for you to do the same for us.
  • If there are any questions or changes, your talent acquisition partner will be available for you.
  • If we decide not to hire you, you’ll receive feedback from us. If you have feedback for us as well, that’s amazing—we love to learn and improve our processes.