In this episode of Call the Doctor, John Readey (@jreadey) introduced GitHub Codespaces and demonstrates their use with the h5pyd repository. Codespaces allow running a repository in the cloud without local setup. The speaker sets up a Codespace for the h5pyd repository, demonstrating its integration with VS Code, terminal access, and execution of h5pyd commands like hsinfo and python test. They showcase practical examples such as reading and writing HDF5 files, leveraging the S3 interface for data access, and utilizing Jupyter notebooks for data analysis. The video highlights how Codespaces simplify environment setup and enable handling large datasets efficiently through HSDS integration.