diff --git a/Project.toml b/Project.toml
index f6b6b6b..e4de621 100644
--- a/Project.toml
+++ b/Project.toml
@@ -13,7 +13,7 @@ ReferenceFrameRotations = "74f56ac7-18b3-5285-802d-d4bd4f104033"
 StaticArrays = "90137ffa-7385-5640-81b9-e52037218182"
 
 [compat]
-GTPSA = "1"
+GTPSA = "1.2.0"
 ReferenceFrameRotations = "3"
 StaticArrays = "1"
 julia = "1.9"
diff --git a/src/BeamTracking.jl b/src/BeamTracking.jl
index eb55cfc..32cad09 100644
--- a/src/BeamTracking.jl
+++ b/src/BeamTracking.jl
@@ -59,6 +59,14 @@ function Beam(
   return Beam(species, coords)
 end
 
+# Creates a Beam as identity GTPSA
+function Beam(d::Descriptor; species::Species=Species("electron"))
+  GTPSA.numvars(d) == 6 || error("Invalid GTPSA Descriptor! Number of variables must be equal to 6.")
+  z = vars(d)
+  return Beam(species, Coords([z[1]], [z[2]], [z[3]], [z[4]], [z[5]], [z[6]]))
+end
+
+
 # --------------------------------------
 
 
diff --git a/src/paraxial/Paraxial.jl b/src/paraxial/Paraxial.jl
index f19fc3d..f644117 100644
--- a/src/paraxial/Paraxial.jl
+++ b/src/paraxial/Paraxial.jl
@@ -1,10 +1,15 @@
 module Paraxial
 using ..BeamTracking: Coords, Beam
 using ..GTPSA
-using ..AcceleratorLattice
+#using ..AcceleratorLattice
+
+struct ParaxialDrift{T}
+  L::T
+end
+
 
 """
-    track!(L, beamf::Beam, beam0::Beam) -> beamf
+    track!(ele::ParaxialDrift, beamf::Beam, beam0::Beam) -> beamf
 
 Routine to tracking through a drift using the paraxial approximation and 
 including higher-order energy effects. 
@@ -14,13 +19,12 @@ including higher-order energy effects.
 - `beamf` -- Output beam after tracking through
 - `beam0` -- Input beam before tracking through
 """
-function track!(ele::Drift, beamf::Beam, beam0::Beam)
+function track!(L, beamf::Beam, beam0::Beam)
   @assert !(beamf === beam0) "Aliasing beamf === beam0 not allowed!"
-  L = ele.L
   z0 = beam0.z
   zf = beamf.z
-
-  @FastGTPSA begin
+  
+  @FastGTPSA! begin
   @. zf[1] = z0[1]+z0[2]*L/(1.0+z0[6])
   @. zf[2] = z0[2]
   @. zf[3] = z0[3]+z0[4]*L/(1.0+z0[6])
@@ -28,7 +32,9 @@ function track!(ele::Drift, beamf::Beam, beam0::Beam)
   @. zf[5] = z0[5]-L*((z0[2]^2)+(z0[4]^2))/(1.0+z0[6])^2/2.0
   @. zf[6] = z0[6] 
   end
+  
   return beamf
 end
 
+
 end
\ No newline at end of file