Giulio Aielli, Juliette Alimena, James Beacham, Eli Ben-Haim, Martino Borsato, Matthew John Charles, Xabier Cid Vidal, Victor Coco, Albert De Roeck, Biplab Dey, Raphael Dumps, Vladimir V. Gligorov, Rebeca Gonzalez Suarez, Thomas Gorordo, Louis Henry, Philip Ilten, Daniel Johnson, Simon Knapen, Olivier Le Dortz, Saul López Soliño, Titus Mombächer, Benjamin Nachman, David T. Northacker, Michele Papucci, Gabriella Pásztor, Luca Pizzimento, Francesco Polci, Dean J. Robinson, Heinrich Schindler, Michael D. Sokoloff, Aditya Suresh, Paul Swallow, Riccardo Vari, Gábor Veres, Carlos Vázquez Sierra, Nigel Watson, Michael K. Wilkinson, Michael Williams, Emilio Xosé Rodríguez Fernández
In this Snowmass contribution we present a comprehensive status update on the progress and plans for the proposed CODEX-b detector, intended to search for long-lived particles beyond the Standard Model. We review the physics case for the proposal and present recent progress on optimization strategies for the detector and shielding design, as well as the development of new fast and full simulation frameworks. A summary of the technical design for a smaller demonstrator detector (CODEX-) for the upcoming Run~3 of the LHC is also discussed, alongside the road towards realization of the full experiment at the High-Luminosity LHC.