diff --git a/groups/caprace.jl b/groups/caprace.jl
index 48d6b31..980421d 100644
--- a/groups/caprace.jl
+++ b/groups/caprace.jl
@@ -1,20 +1,14 @@
-module CapraceGroup
+struct CapraceGroup <: GAPGroup
+    args::Dict{String,Any}
+end
 
-using AbstractAlgebra
-using Groups
+name(G::CapraceGroup) = "CapraceGroup"
 
-###############################################################################
-#
-#  Generating set
-#
-###############################################################################
+function group(G::CapraceGroup)
 
-Comm(x,y) = x*y*x^-1*y^-1
+   caprace_group = Groups.FPGroup(["x","y","z","t","r"])
 
-function generatingset()
-
-   CapraceGroup = Groups.FPGroup(["x","y","z","t","r"]);
-   x,y,z,t,r = gens(CapraceGroup)
+   x,y,z,t,r = gens(caprace_group)
 
    relations = [
    x^7,
@@ -38,25 +32,6 @@ function generatingset()
 
    relations = [relations; [inv(rel) for rel in relations]]
 
-   Groups.add_rels!(CapraceGroup, Dict(rel => CapraceGroup() for rel in relations))
-
-   return CapraceGroup, gens(CapraceGroup)
+   Groups.add_rels!(caprace_group, Dict(rel => caprace_group() for rel in relations))
+   return caprace_group
 end
-
-function generatingset(parsed_args)
-   return generatingset()
-end
-
-###############################################################################
-#
-#  Misc
-#
-###############################################################################
-
-function groupname(parsed_args)
-    return groupname(), 0
-end
-
-groupname() = "CapraceGroup"
-
-end # of module CapraceGroup
diff --git a/groups/higman.jl b/groups/higman.jl
index 041a015..74b0af2 100644
--- a/groups/higman.jl
+++ b/groups/higman.jl
@@ -1,49 +1,24 @@
-module HigmanGroup
+struct HigmanGroup <: GAPGroup
+    args::Dict{String,Any}
+end
 
-using AbstractAlgebra
-using Groups
+name(G::HigmanGroup) = "HigmanGroup"
 
-###############################################################################
-#
-#  Generating set
-#
-###############################################################################
+function group(G::HigmanGroup)
 
-Comm(x,y) = x*y*x^-1*y^-1
+   higman_group = Groups.FPGroup(["a","b","c","d"]);
 
-function generatingset()
-
-   HigmanGr = Groups.FPGroup(["a","b","c","d"]);
-   a,b,c,d = gens(HigmanGr)
+   a,b,c,d = gens(higman_group)
 
    relations = [
-      b^-1*Comm(b,a),
-      c^-1*Comm(c,b),
-      d^-1*Comm(d,c),
-      a^-1*Comm(a,d)
+   b^-1*Comm(b,a),
+   c^-1*Comm(c,b),
+   d^-1*Comm(d,c),
+   a^-1*Comm(a,d)
    ];
 
    relations = [relations; [inv(rel) for rel in relations]]
 
-   Groups.add_rels!(HigmanGr, Dict(rel => HigmanGr() for rel in relations))
-
-   return HigmanGr, gens(HigmanGr)
+   Groups.add_rels!(higman_group, Dict(rel => HigmanGr() for rel in relations))
+   return higman_group
 end
-
-function generatingset(parsed_args)
-   return generatingset()
-end
-
-###############################################################################
-#
-#  Misc
-#
-###############################################################################
-
-function groupname(parsed_args)
-    return groupname(), 0
-end
-
-groupname() = "HigmanGroup"
-
-end # of module CapraceGroup
diff --git a/groups/mappingclassgroup.jl b/groups/mappingclassgroup.jl
index ea44aff..500dceb 100644
--- a/groups/mappingclassgroup.jl
+++ b/groups/mappingclassgroup.jl
@@ -1,17 +1,14 @@
-module MappingClassGroups
+struct MappingClassGroup <: GAPGroup
+    args::Dict{String,Any}
+end
 
-using AbstractAlgebra
-using Groups
+function name(G::MappingClassGroup)
+    N = G.args["N"]
+    return "MCG($(N))"
+end
 
-###############################################################################
-#
-#  Generating set
-#
-###############################################################################
-
-Comm(x,y) = x*y*x^-1*y^-1
-
-function generatingset(N::Int)
+function group(G::MappingClassGroup)
+    N = G.args["N"]
     if N < 2
         throw("Genus must be at least 2!")
     elseif N == 2
@@ -33,77 +30,57 @@ function generatingset(N::Int)
        Groups.add_rels!(MCGroup, Dict(rel => MCGroup() for rel in relations))
        return MCGroup
 
-    end
+    else
+        MCGroup = Groups.FPGroup(["a$i" for i in 0:2N])
+        S = gens(MCGroup)
 
-    MCGroup = Groups.FPGroup(["a$i" for i in 0:2N])
-    S = gens(MCGroup)
+        a0 = S[1]
+        A = S[2:end]
+        k = length(A)
 
-    a0 = S[1]
-    A = S[2:end]
-    k = length(A)
+        relations = [
+            [Comm(A[i], A[j]) for i in 1:k for j in 1:k if abs(i-j) > 1]...,
+            [Comm(a0, A[i]) for i in 1:k if i != 4]...,
+            [A[i]*A[(i+1)]*A[i]*inv(A[i+1]*A[i]*A[i+1]) for i in 1:k-1]...,
+            A[4]*a0*A[4]*inv(a0*A[4]*a0)
+            ]
 
-    relations = [
-        [Comm(A[i], A[j]) for i in 1:k for j in 1:k if abs(i-j) > 1]...,
-        [Comm(a0, A[i]) for i in 1:k if i != 4]...,
-        [A[i]*A[(i+1)]*A[i]*inv(A[i+1]*A[i]*A[i+1]) for i in 1:k-1]...,
-        A[4]*a0*A[4]*inv(a0*A[4]*a0)
-        ]
+        # 3-chain relation
+        c = prod(reverse(A[1:4]))*prod(A[1:4])
+        b0 = c*a0*inv(c)
+        push!(relations, (A[1]*A[2]*A[3])^4*inv(a0*b0))
 
-    # 3-chain relation
-    c = prod(reverse(A[1:4]))*prod(A[1:4])
-    b0 = c*a0*inv(c)
-    push!(relations, (A[1]*A[2]*A[3])^4*inv(a0*b0))
+        # Lantern relation
+        b1 = inv(A[4]*A[5]*A[3]*A[4])*a0*(A[4]*A[5]*A[3]*A[4])
+        b2 = inv(A[2]*A[3]*A[1]*A[2])*b1*(A[2]*A[3]*A[1]*A[2])
+        u  = inv(A[6]*A[5])*b1*(A[6]*A[5])
+        x  = prod(reverse(A[2:6]))*u*prod(inv.(A[1:4]))
+        b3 = x*a0*inv(x)
+        push!(relations, a0*b2*b1*inv(A[1]*A[3]*A[5]*b3))
 
-    # Lantern relation
-    b1 = inv(A[4]*A[5]*A[3]*A[4])*a0*(A[4]*A[5]*A[3]*A[4])
-    b2 = inv(A[2]*A[3]*A[1]*A[2])*b1*(A[2]*A[3]*A[1]*A[2])
-    u  = inv(A[6]*A[5])*b1*(A[6]*A[5])
-    x  = prod(reverse(A[2:6]))*u*prod(inv.(A[1:4]))
-    b3 = x*a0*inv(x)
-    push!(relations, a0*b2*b1*inv(A[1]*A[3]*A[5]*b3))
+        # Hyperelliptic relation
+        X = prod(reverse(A))*prod(A)
 
-    # Hyperelliptic relation
-    X = prod(reverse(A))*prod(A)
-
-    function n(i::Int, b=b0)
-        if i == 1
-            return A[1]
-        elseif i == 2
-            return b
-        else
-            return w(i-2)*n(i-2)*w(i-2)
+        function n(i::Int, b=b0)
+            if i == 1
+                return A[1]
+            elseif i == 2
+                return b
+            else
+                return w(i-2)*n(i-2)*w(i-2)
+            end
         end
+
+        function w(i::Int)
+           (A[2i+4]*A[2i+3]*A[2i+2]* n(i+1))*(A[2i+1]*A[2i]  *A[2i+2]*A[2i+1])*
+           (A[2i+3]*A[2i+2]*A[2i+4]*A[2i+3])*( n(i+1)*A[2i+2]*A[2i+1]*A[2i]  )
+        end
+
+        # push!(relations, X*n(N)*inv(n(N)*X))
+
+        relations = [relations; [inv(rel) for rel in relations]]
+        Groups.add_rels!(MCGroup, Dict(rel => MCGroup() for rel in relations))
+
+        return MCGroup
     end
-
-    function w(i::Int)
-       (A[2i+4]*A[2i+3]*A[2i+2]* n(i+1))*(A[2i+1]*A[2i]  *A[2i+2]*A[2i+1])*
-       (A[2i+3]*A[2i+2]*A[2i+4]*A[2i+3])*( n(i+1)*A[2i+2]*A[2i+1]*A[2i]  )
-    end
-
-    # push!(relations, X*n(N)*inv(n(N)*X))
-
-    relations = [relations; [inv(rel) for rel in relations]]
-    Groups.add_rels!(MCGroup, Dict(rel => MCGroup() for rel in relations))
-
-    return MCGroup, gens(MCGroup)
 end
-
-function generatingset(parsed_args)
-    N = parsed_args["N"]
-    return generatingset(N)
-end
-
-###############################################################################
-#
-#  Misc
-#
-###############################################################################
-
-function groupname(parsed_args)
-    N = parsed_args["N"]
-    return groupname(N), N
-end
-
-groupname(N::Int) = "MCG$(N)"
-
-end #of module MappingClassGroups