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[EN] All-optical helicity-dependent switching in ferromagnetic layers has revealed an unprecedented route to manipulate magnetic configurations by circularly polarized femtosecond laser pulses. In this work, rare-earth free synthetic ferrimagnetic heterostructures made from two antiferromagnetically exchange coupled ferromagnetic layers are studied. Experimental results, supported by numerical simulations, show that the designed structures enable all-optical switching which is controlled, not only by light helicity, but also by the relative Curie temperature of each ferromagnetic layer. Indeed, through the antiferromagnetic exchange coupling, the layer with the larger Curie temperature determines the final orientation of the other layer and so the synthetic ferrimagnet. For similar Curie temperatures, helicity-independent back switching is observed and the final magnetic configuration is solely determined by the initial magnetic state. This demonstration of electrically-detected, optical control of engineered rare-earth free heterostructures opens a novel route toward practical opto-spintronics. ; Newton International Fellowship scheme NF150217 Deutsche Forschungsgemeinschaft tSFB/TRR 227 "Ultrafast Spin Dynamics," Project A08 UK EPSRC (Grant No. EP/P005713/1). Institut Carnot ICEEL for the project "Optic-switch" and Matelas and by the French PIA project "Lorraine Université d'Excellence," (Ref. No. ANR-151DEX-04-LUE) FEDER (EU), ANR, Région Grand Est, and Métropole Grand Nancy Project No. MAT2017-87072-C4-1-P from the (Ministerio de Economia y Competitividad) Spanish government SA299P18 from Consejeria de Educacion Junta de Castilla y Leon.