The tyrosine kinase expressed in hepatocellular carcinoma (TEC) family comprises five non-receptor tyrosine kinases – BTK, ITK, BMX, TXK, and TEC – with key roles in immune signalling. Although BTK and ITK have been extensively studied, selective inhibitors for TEC, TXK, and BMX remain scarce. Recently, we identified 7-azaindole-based covalent BMX inhibitors with potent inhibitory activity and robust cellular target engagement but limited selectivity across TEC family members, especially BTK. He