Tuning materials properties on demand is at the heart of solid-state physics. Charge transport and magnetism are strongly linked to the overlap of electronic wave functions and can be, thus, manipulated by varying the electronic bandwidth through chemical substitution or physical pressure. Yet, a controlled modification of geometrical frustration of transfer integrals and exchange interactions remained inaccessible so far. Here, we utilize the recent advancements in strain tuning of unconventional superconductors [1-3] and apply uniaxial stress to a clean kagome-lattice system without disorder [4]. As we break the hexagonal symmetry in a continuous manner, we achieve in situ tuning of antiferromagnetic order within one single crystal through a controlled release of frustration strength [4], see Fig. 1(a). We further apply uniaxial strain to fine-tune the Mott transition with unprecedented precision [5]. Our pioneering endeavors [4,5] demonstrate uniaxial strain as a powerful tool to tweak interacting electrons on frustrated lattices – with the prospect of tuning frustration-induced topological flat bands [Fig. 1(b-d)], e.g. in kagome systems such as Ni3In [6,7], that may be applied to generate ‘green’ energy from metallic thermoelectrics [8]. References 1. C.W. Hicks et al., Science 344, 283 LP (2014). 2. A. Pustogow et al., Nature 574, 72–75 (2019). 3. A. Chronister et al., npj Quantum Mater. 7, 113 (2022). 4. Jierong Wang, Y.-S. Su, M. Spitaler, K.M. Zoch, C. Krellner, P. Puphal, S.E. Brown, and A. Pustogow, Phys. Rev. Lett. 131, 256501 (2023). 5. A. Pustogow, Y. Kawasugi, H. Sakurakoji, N. Tajima, Nat. Commun. 14, 1960 (2023). 6. L. Ye et al., Nat. Phys. 20, 610 (2024). 7. H. J. Kim, M. J. Kim, J. Lee, J. M. Ok, and C.-J. Kang, Phys. Rev. B 110, 024504 (2024). 8. F. Garmroudi, I. Serhiienko, S. Di Cataldo, M. Parzer, A. Riss, M. Grasser, S. Stockinger, S. Khmelevskyi, K. Pryga, B. Wiendlocha, K. Held, T. Mori, E. Bauer, and A. Pustogow, e-print arXiv:2404.08067