BLURR is a library that integrates Hugging Face transformers with fastai for NLP tasks. It provides high-level, mid-level, and low-level APIs to train and deploy transformer models for text classification, token classification, question answering, summarization, translation, and language modeling. The library leverages fastai's data block API and learner system, wrapping Hugging Face models to work seamlessly within the fastai training loop. Key components include custom data blocks for text processing, model wrappers for Hugging Face integration, specialized loss functions, and callbacks for optimization. The repository includes extensive examples and notebooks demonstrating usage with standard datasets like GLUE, SQuAD, and CNN/DailyMail.