This paper presents a pattern language for user experiences in live coding. It uses a recently defined analytic framework that has developed out of the Cognitive Dimensions of Notations and related approaches. The focus on performance programming offers particular value in its potential to construct rigorous accounts of the experiences of both performers (the live coder) and audiences. Although developed as an account of live coding, the findings promise to be relevant to a wider range of performance programming contexts, which could benefit from analysis in terms of live coding, if a systematic framework of this kind were available. The paper provides a detailed analytic commentary, drawing on the broadly diverse body of prior live coding practice, but using music live coding as a central running example. The findings demonstrate the advantage of rigorous analysis from an independent theoretical perspective, and suggest the potential for future work that might draw on this pattern language as a basis for empirical investigations of user experience, and as a theoretical grounding in practice-led design of new live coding languages and tools.