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We present MIRI/JWST medium resolution spectroscopy (MRS) and imaging (MIRIM)of the lensed galaxy MACS1149-JD1 at a redshift of $z$=9.1092$\pm$0.0002(Universe age about 530 Myr). We detect, for the first time, spatially-resolvedH$\alpha$ emission in a galaxy at redshift above 9. The structure of theH$\alpha$ emitting gas consists of two clumps, S and N. The total H$\alpha$luminosity implies an instantaneous star formation rate of 5.3$\pm$0.4$M_{\odot}$ yr$^{-1}$ for solar metallicities. The ionizing photon productionefficiency, $\log(\zeta_\mathrm{ion})$, shows a spatially-resolved structurewith values of 25.55$\pm$0.03, 25.47$\pm$0.03, and 25.91$\pm$0.09 Hz erg$^{-1}$for the integrated galaxy, and clumps S and N, respectively. The H$\alpha$rest-frame equivalent width, EW$_{0}$(H$\alpha$), is 491$^{+334}_{-128}$\'Angstrom for the integrated galaxy, but presents extreme values of363$^{+187}_{-87}$ \'Angstrom and $\geq$1543 \'Angstrom for clumps S and N,respectively. The spatially-resolved ionizing photon production efficiency iswithin the range of values measured in galaxies at redshift above six, and wellabove the canonical value (25.2$\pm$0.1 Hz erg$^{-1}$). The extreme differenceof EW$_{0}$(H$\alpha$) for Clumps S and N indicates the presence of a recent(few Myr old) burst in clump N and a star formation over a larger period oftime (e.g. 100$-$200 Myr) in clump S. Finally, clump S and N show verydifferent H$\alpha$ kinematics with velocity dispersions of 56$\pm$4 kms$^{-1}$ and 113$\pm$33 km s$^{-1}$, likely indicating the presence of outflowsor increased turbulence in the clump N. The dynamical mass, $M_\mathrm{dyn}$=(2.4$\pm$0.5)$\times$10$^{9}$ $M_{\odot}$, is within the range previouslymeasured with the spatially-resolved [OIII]88$\mu$m line.

Spatially-resolved H$\alpha$ and ionizing photon production efficiency in the lensed galaxy MACS1149-JD1 at a redshift of 9.11