Tutorial: integrating free NMT and LLMs into CAT tools with MTUOC
Sergi Alvarez-Vidal and Antoni Oliver
The landscape of machine translation (MT) has evolved dramatically since the advent of neural MT (NMT), which marked a breakthrough in translation quality and fluency. More recently, the rise of large language models (LLMs) has reshaped this landscape once again, introducing a new paradigm that merges translation, adaptation, and post-editing within a unified framework of multilingual text generation. These advances are expanding the possibilities for translators and language professionals, offering tools that can be tailored to domain-specific needs and local workflows. While commercial systems such as DeepL, Google Translate, ChatGPT, or Gemini dominate public attention, a vibrant ecosystem of free and open-source NMT and LLM resources has emerged. Projects like OPUS-MT, NLLB, and translation-oriented open LLMs such as Tower and Salamandra make it increasingly feasible to build and adapt high-quality MT pipelines for specific languages, domains, or institutional contexts. Yet, integrating these tools—each with its own dependencies and APIs—into professional computer-assisted translation (CAT) environments remains a technical challenge.
The MTUOC project addresses this gap by providing a comprehensive open-source framework that simplifies deployment and integration. This hands-on tutorial will guide participants in building and customizing their own tailored MT ecosystems using fully open and free technologies. Attendees will learn how to (1) set up the MTUOC-server, (2) deploy leading open models such as OpusMT and NLLB, (3) integrate translation-specialized LLMs (Tower, Salamandra) through MTUOC components, and (4) connect all these tools seamlessly within OmegaT, a widely used open-source CAT platform. By the end of the session, participants will have a fully operational and reproducible open-source translation workflow capable of combining neural MT and LLM-based translation within a professional environment. Since both MTUOC and OmegaT are distributed under the GNU-GPL license, the entire solution remains free, extensible, and adaptable to the needs of individual translators, research groups, and institutions.