Disclosed herein are pyrrolo[2,3-d]pyrimidine compounds that form covalent bonds with Bruton's tyrosine kinase (Btk). Also described are irreversible inhibitors of Btk. In addition, reversible inhibitors of Btk are also described. Also disclosed are pharmaceutical compositions that include the compounds. Methods of using the Btk inhibitors disclosed, alone or in combination with other therapeutic agents, for the treatment of autoimmune diseases or conditions, heteroimmune diseases or conditions, cancer, including lymphoma, and inflammatory diseases or conditions.