The nature of the superconducting pairing symmetry in the kagome metal ${\mathrm{CsV}}_3{\mathrm{Sb}}_5$ and its relationship with the charge density wave (CDW) order are central unresolved issues. Here, we investigate the evolution of superconductivity in ${\mathrm{CsV}}_3{\mathrm{Sb}}_5$ under in situ uniaxial pressure using ${}^{121}\mathrm{Sb}$ nuclear quadrupole resonance (NQR). We find that tensile strain significantly enhances the superconducting transition temperature, $T_{\mathrm{c}}$, while the CDW remains unchanged, demonstrating that superconductivity can be tuned independently of the bulk charge order. At a tensile strain of $ϵ=+0.90\%$, the nuclear spin-lattice relaxation rate reveals a remarkable double transition: an upper transition at $T_{\mathrm{c}1}=3.6\mathrm{K}$ to a nodal gap state, and a lower one at $T_{\mathrm{c}2}=3.0\mathrm{K}$ characterized by a nodeless gap. These results evidence degenerate superconducting states with different gap symmetry in the kagome metal at ambient pressure which split under strain. Our Letter demonstrates a high tunability of superconductivity by uniaxial pressure.

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• Charge density waves
• Strain
• Superconductivity
• Unconventional superconductors
• Nuclear magnetic resonance