diff --git a/src/containers/building_blocks.jl b/src/containers/building_blocks.jl
index f3aa83dd1668cad53c8130eebfcfa973b1a842c3..f4b26249c25a79a190250cc35c16035950531e7a 100644
--- a/src/containers/building_blocks.jl
+++ b/src/containers/building_blocks.jl
@@ -5,8 +5,9 @@ module BuildingBlocks
 import LinearAlgebra: norm
 import JuMP: @constraint
 import ..Abstract: ContainerBlock
+import ...BuildSequences: global_model
 import ...Components: BaseComponent, GradientWaveform, EventComponent, NoGradient, ChangingGradient, ConstantGradient, split_gradient, DelayedEvent, RFPulseComponent, ReadoutComponent
-import ...Variables: qval, bmat_gradient, effective_time
+import ...Variables: qval, bmat_gradient, effective_time, get_free_variable
 import ...Variables: VariableType, duration, make_generic, get_pulse, get_readout, scanner_constraints!
 
 """