diff --git a/makefiles/Makefile.dotnet.mk b/makefiles/Makefile.dotnet.mk
index c82843bcdf..b6c069b865 100644
--- a/makefiles/Makefile.dotnet.mk
+++ b/makefiles/Makefile.dotnet.mk
@@ -179,26 +179,61 @@ $(OBJ_DIR)/swig/sat_csharp_wrap.$O: \
  $(OBJ_OUT)$(OBJ_DIR)$Sswig$Ssat_csharp_wrap.$O
 
 # Protobufs
-$(GEN_DIR)/com/google/ortools/constraintsolver/SearchLimit.g.cs: $(SRC_DIR)/ortools/constraint_solver/search_limit.proto
-	$(PROTOC) --proto_path=$(SRC_DIR) --csharp_out=$(GEN_DIR)$Scom$Sgoogle$Sortools$Sconstraintsolver --csharp_opt=file_extension=.g.cs $(SRC_DIR)$Sortools$Sconstraint_solver$Ssearch_limit.proto
+$(GEN_DIR)/com/google/ortools/constraintsolver/SearchLimit.g.cs: \
+ $(SRC_DIR)/ortools/constraint_solver/search_limit.proto | \
+ $(GEN_DIR)/com/google/ortools/constraintsolver
+	$(PROTOC) --proto_path=$(SRC_DIR) \
+ --csharp_out=$(GEN_DIR)$Scom$Sgoogle$Sortools$Sconstraintsolver \
+ --csharp_opt=file_extension=.g.cs \
+ $(SRC_DIR)$Sortools$Sconstraint_solver$Ssearch_limit.proto
 
-$(GEN_DIR)/com/google/ortools/constraintsolver/SolverParameters.g.cs: $(SRC_DIR)/ortools/constraint_solver/solver_parameters.proto
-	$(PROTOC) --proto_path=$(SRC_DIR) --csharp_out=$(GEN_DIR)$Scom$Sgoogle$Sortools$Sconstraintsolver --csharp_opt=file_extension=.g.cs $(SRC_DIR)$Sortools$Sconstraint_solver$Ssolver_parameters.proto
+$(GEN_DIR)/com/google/ortools/constraintsolver/SolverParameters.g.cs: \
+ $(SRC_DIR)/ortools/constraint_solver/solver_parameters.proto | \
+ $(GEN_DIR)/com/google/ortools/constraintsolver
+	$(PROTOC) --proto_path=$(SRC_DIR) \
+ --csharp_out=$(GEN_DIR)$Scom$Sgoogle$Sortools$Sconstraintsolver \
+ --csharp_opt=file_extension=.g.cs \
+ $(SRC_DIR)$Sortools$Sconstraint_solver$Ssolver_parameters.proto
 
-$(GEN_DIR)/com/google/ortools/constraintsolver/Model.g.cs: $(SRC_DIR)/ortools/constraint_solver/solver_parameters.proto
-	$(PROTOC) --proto_path=$(SRC_DIR) --csharp_out=$(GEN_DIR)$Scom$Sgoogle$Sortools$Sconstraintsolver --csharp_opt=file_extension=.g.cs $(SRC_DIR)$Sortools$Sconstraint_solver$Smodel.proto
+$(GEN_DIR)/com/google/ortools/constraintsolver/Model.g.cs: \
+ $(SRC_DIR)/ortools/constraint_solver/solver_parameters.proto | \
+ $(GEN_DIR)/com/google/ortools/constraintsolver
+	$(PROTOC) --proto_path=$(SRC_DIR) \
+ --csharp_out=$(GEN_DIR)$Scom$Sgoogle$Sortools$Sconstraintsolver \
+ --csharp_opt=file_extension=.g.cs \
+ $(SRC_DIR)$Sortools$Sconstraint_solver$Smodel.proto
 
-$(GEN_DIR)/com/google/ortools/constraintsolver/RoutingParameters.g.cs: $(SRC_DIR)/ortools/constraint_solver/routing_parameters.proto
-	$(PROTOC) --proto_path=$(SRC_DIR) --csharp_out=$(GEN_DIR)$Scom$Sgoogle$Sortools$Sconstraintsolver --csharp_opt=file_extension=.g.cs $(SRC_DIR)$Sortools$Sconstraint_solver$Srouting_parameters.proto
+$(GEN_DIR)/com/google/ortools/constraintsolver/RoutingParameters.g.cs: \
+ $(SRC_DIR)/ortools/constraint_solver/routing_parameters.proto | \
+ $(GEN_DIR)/com/google/ortools/constraintsolver
+	$(PROTOC) --proto_path=$(SRC_DIR) \
+ --csharp_out=$(GEN_DIR)$Scom$Sgoogle$Sortools$Sconstraintsolver \
+ --csharp_opt=file_extension=.g.cs \
+ $(SRC_DIR)$Sortools$Sconstraint_solver$Srouting_parameters.proto
 
-$(GEN_DIR)/com/google/ortools/constraintsolver/RoutingEnums.g.cs: $(SRC_DIR)/ortools/constraint_solver/routing_enums.proto
-	$(PROTOC) --proto_path=$(SRC_DIR) --csharp_out=$(GEN_DIR)$Scom$Sgoogle$Sortools$Sconstraintsolver --csharp_opt=file_extension=.g.cs $(SRC_DIR)$Sortools$Sconstraint_solver$Srouting_enums.proto
+$(GEN_DIR)/com/google/ortools/constraintsolver/RoutingEnums.g.cs: \
+ $(SRC_DIR)/ortools/constraint_solver/routing_enums.proto | \
+ $(GEN_DIR)/com/google/ortools/constraintsolver
+	$(PROTOC) --proto_path=$(SRC_DIR) \
+ --csharp_out=$(GEN_DIR)$Scom$Sgoogle$Sortools$Sconstraintsolver \
+ --csharp_opt=file_extension=.g.cs \
+ $(SRC_DIR)$Sortools$Sconstraint_solver$Srouting_enums.proto
 
-$(GEN_DIR)/com/google/ortools/sat/CpModel.g.cs: $(SRC_DIR)/ortools/sat/cp_model.proto
-	$(PROTOC) --proto_path=$(SRC_DIR) --csharp_out=$(GEN_DIR)$Scom$Sgoogle$Sortools$Ssat --csharp_opt=file_extension=.g.cs $(SRC_DIR)$Sortools$Ssat$Scp_model.proto
+$(GEN_DIR)/com/google/ortools/sat/CpModel.g.cs: \
+ $(SRC_DIR)/ortools/sat/cp_model.proto | \
+ $(GEN_DIR)/com/google/ortools/sat
+	$(PROTOC) --proto_path=$(SRC_DIR) \
+ --csharp_out=$(GEN_DIR)$Scom$Sgoogle$Sortools$Ssat \
+ --csharp_opt=file_extension=.g.cs \
+ $(SRC_DIR)$Sortools$Ssat$Scp_model.proto
 
-$(GEN_DIR)/com/google/ortools/sat/SatParameters.g.cs: $(SRC_DIR)/ortools/sat/sat_parameters.proto
-	$(PROTOC) --proto_path=$(SRC_DIR) --csharp_out=$(GEN_DIR)$Scom$Sgoogle$Sortools$Ssat --csharp_opt=file_extension=.g.cs $(SRC_DIR)$Sortools$Ssat$Ssat_parameters.proto
+$(GEN_DIR)/com/google/ortools/sat/SatParameters.g.cs: \
+ $(SRC_DIR)/ortools/sat/sat_parameters.proto | \
+ $(GEN_DIR)/com/google/ortools/sat
+	$(PROTOC) --proto_path=$(SRC_DIR) \
+ --csharp_out=$(GEN_DIR)$Scom$Sgoogle$Sortools$Ssat \
+ --csharp_opt=file_extension=.g.cs \
+ $(SRC_DIR)$Sortools$Ssat$Ssat_parameters.proto
 
 $(CLR_KEYFILE):
 ifdef CLR_KEYFILE