diff --git a/Project.toml b/Project.toml
index 58b50cd..f72ff54 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,8 +1,7 @@
 name = "SimpleQuantum"
 uuid = "7c07e4e5-e402-48af-840a-a11b8ea3e28c"
 authors = ["Tomas Polakovic <tom.polakovic@gmail.com> and contributors"]
-version = "0.2.3"
-
+version = "0.2.4"
 
 [deps]
 Accessors = "7d9f7c33-5ae7-4f3b-8dc6-eff91059b697"
@@ -15,6 +14,7 @@ Match = "7eb4fadd-790c-5f42-8a69-bfa0b872bfbf"
 RangeHelpers = "3a07dd3d-1c52-4395-8858-40c6328157db"
 SplitApplyCombine = "03a91e81-4c3e-53e1-a0a4-9c0c8f19dd66"
 StaticArrays = "90137ffa-7385-5640-81b9-e52037218182"
+SymmetryReduceBZ = "49a35663-c880-4242-bebb-1ec8c0fa8046"
 Unitful = "1986cc42-f94f-5a68-af5c-568840ba703d"
 
 [compat]
diff --git a/src/SimpleQuantum.jl b/src/SimpleQuantum.jl
index 09a5e5b..a1acc66 100644
--- a/src/SimpleQuantum.jl
+++ b/src/SimpleQuantum.jl
@@ -10,6 +10,7 @@ using Colors
 using GLMakie
 using Accessors
 using Combinatorics
+using SymmetryReduceBZ
 
 include("crystal.jl")
 include("interface.jl")
diff --git a/src/crystal.jl b/src/crystal.jl
index 0e5ae23..5ac7b5e 100644
--- a/src/crystal.jl
+++ b/src/crystal.jl
@@ -204,30 +204,7 @@ end
 Calculates the point symmetry group operations of `c`.
 """
 function getPG(c::Crystal)
-    D = ndims(c)
-    # TODO: I think Minkowski reduction might be good here.
-    R = c.lattice.R |> Matrix
-    iR = SMatrix{D,D}(inv(R))
-    norms = mapslices(norm, R; dims=1)
-    vol = c.lattice.V
-    ls = round.(norms) .+ 1
-    verts = (Iterators.product(ntuple(i -> -ls[i]:ls[i], D)...)
-             .|> collect
-              |> x -> reshape(x, :, 1)
-              |> combinedims)[:,:,1]
-    out = SMatrix{D,D}[]
-    for perm ∈ permutations(1:size(verts, 2), D)
-        vs = R * verts[:, perm]
-        _norms = mapslices(norm, vs; dims=1)
-        _vol = abs(det(vs))
-        if all(norms ≈ _norms) & all(vol ≈ _vol)
-            op = SMatrix{D,D}(vs * iR)
-            if all(op' * op ≈ I)
-                append!(out, [op])
-            end
-        end
-    end
-    out
+    SymmetryReduceBZ.Symmetry.calc_pointgroup(c.lattice.R)
 end
 
 """
diff --git a/src/interface.jl b/src/interface.jl
index 2a89e5f..6a0d526 100644
--- a/src/interface.jl
+++ b/src/interface.jl
@@ -1,24 +1,24 @@
-struct ReciprocalPath
-    ks::Vector{Union{<:Real, Vector{<:Real}}}
-    kp::Vector{<:Real}
-    kl::Vector{Pair{Symbol, <:Real}}
-end
+######################################################################################
+abstract type GenericHamiltonian end
 
-abstract type ReciprocalHamiltonian end
+# function Base.ndims(t::T) where {T <: GenericHamiltonian}
+#     error(typeof(t), " needs to have `ndims` defined.")
+# end
 
-function Base.ndims(t::T) where {T <: ReciprocalHamiltonian}
-    e = typeof(t)
-    throw(ArgumentError("$e needs to have `ndims` defined."))
+function getH(t::T) where {T <: GenericHamiltonian}
+    error(typeof(t), " needs to have `getH` defined.")
 end
 
-function getH(t::T) where {T <: ReciprocalHamiltonian}
-    e = typeof(t)
-    throw(ArgumentError("$e needs to have `getH` defined."))
+abstract type ReciprocalHamiltonian <: GenericHamiltonian end
+
+function (h::ReciprocalHamiltonian)(k)
+    getH(h)(k)
 end
 
-struct ReciprocalBandProblem
-    h::ReciprocalHamiltonian
-    kp::ReciprocalPath
+struct ReciprocalPath
+    ks::Vector{Union{<:Real, Vector{<:Real}}}
+    kp::Vector{<:Real}
+    kl::Vector{Pair{Symbol, <:Real}}
 end
 
 function ReciprocalPath(kpositions::Vector, kstep::Real)
@@ -26,20 +26,19 @@ function ReciprocalPath(kpositions::Vector, kstep::Real)
     ReciprocalPath(k.path, k.plength, k.ppoints)
 end
 
-function (h::ReciprocalHamiltonian)(k)
-    getH(h)(k)
+struct ReciprocalBandProblem
+    h::ReciprocalHamiltonian
+    kp::ReciprocalPath
 end
 
-function (rp::ReciprocalPath)(h::ReciprocalHamiltonian)
+function (h::ReciprocalHamiltonian)(rp::ReciprocalPath)
     ReciprocalBandProblem(h, rp)
 end
 
-function (h::ReciprocalHamiltonian)(rp::ReciprocalPath)
+function (rp::ReciprocalPath)(h::ReciprocalHamiltonian)
     ReciprocalBandProblem(h, rp)
 end
 
-# abstract type Solution end
-
 """
     BandSolution