Machine Learning / NLP Engineer

Synthflow AI is a no-code platform for deploying voice AI agents that automate phone calls across contact center operations and business process outsourcing (BPO) at scale. We help mid-market and enterprise companies manage routine calls to save teams time and resources.

Our agents have already delivered measurable impact:

• Over 5 million hours of contact center operations saved

• 35% more calls answered compared to non-AI operators

• 45 million calls handled with a 99.9% uptime

Backed by Accel, Atlantic Labs, and Singular and trusted by over 1,000 customers, our growth leads an industry shift toward sophisticated and accessible conversational AI.

About the Role We’re looking for a talented Machine Learning Engineer / NLP Working student who can bridge research and production. You’ll work on cutting-edge NLP projects involving LLMs, Transformers, and Retrieval-Augmented Generation (RAG), building systems that actually ship to users—not just stay in notebooks.

At Synthflow, we power over one million voice AI calls every day. You’ll help bring AI to life, solving real-world problems at a massive scale. Our team works closely with companies like OpenAI, Google and Mistral. Getting early access to models and shaping their roadmap. You will play a contributing role in this.

Responsibilities

• Implement, fine-tune, and evaluate models such as BERT, Transformers, and modern LLMs.

• Build and optimize RAG pipelines for production use cases.

• Conduct LLM evaluations and benchmarking for accuracy, latency, and robustness.

• Collaborate with engineers and researchers to integrate ML models into our platform.

Requirements

• Strong Python skills and experience writing clean, maintainable production code (not only Jupyter notebooks).

• Hands-on experience with PyTorch or similar frameworks.

• Solid understanding of Transformers, BERT, LLMs, and deep learning fundamentals.

• Familiarity with NLP tasks such as text classification, QA, summarization, and semantic search.

• Interest in applied ML research and the ability to read & implement recent papers.

• Master’s degree (or currently pursuing a Master’s) in Computer Science or a closely related field; ideally with excellent academic performance.

Nice-to-Haves

• Experience with audio/acoustic ML: ASR (automatic speech recognition) and TTS (text-to-speech).

• Experience with vector databases (e.g., Qdrant, Pinecone, Weaviate).

• Exposure to LangChain, LlamaIndex, or other LLM orchestration tools.

• Understanding of LLM evaluation techniques and metrics.

What We Offer

• Opportunity to work with cutting-edge LLM, NLP, and speech AI technology.

• Hands-on mentorship and the ability to ship real products that solve customer needs.

• Flexible work environment and growth opportunities.

• The ability to publish your work in blog posts or academic journals.

Founded in Berlin in 2023 by serial entrepreneurs Albert Astabatsyan, Hakob Astabatsyan, and Sassun Mirzakhan-Saky, Synthflow AI democratizes access to advanced voice AI with a no-code platform that lets enterprises easily create, deploy and scale natural-sounding, cost-effective voice agents tailored to their business needs.