diff --git a/Project.toml b/Project.toml
index 90de204..c01c637 100644
--- a/Project.toml
+++ b/Project.toml
@@ -9,14 +9,3 @@ SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 
 [compat]
 julia = "1.6"
-
-[extras]
-Groups = "5d8bd718-bd84-11e8-3b40-ad14f4a32557"
-GroupsCore = "d5909c97-4eac-4ecc-a3dc-fdd0858a4120"
-PermutationGroups = "8bc5a954-2dfc-11e9-10e6-cd969bffa420"
-Pkg = "44cfe95a-1eb2-52ea-b672-e2afdf69b78f"
-Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
-Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
-
-[targets]
-test = ["Pkg", "Groups", "GroupsCore", "PermutationGroups", "Random", "Test"]
diff --git a/src/bases.jl b/src/bases.jl
index cd893b1..80785e1 100644
--- a/src/bases.jl
+++ b/src/bases.jl
@@ -11,7 +11,7 @@ abstract type AbstractBasis{T,I} end
 
 Base.eltype(::Type{<:AbstractBasis{T}}) where {T} = T
 Base.keytype(::Type{<:AbstractBasis{T,I}}) where {T,I} = I
-Base.keytype(b::AbstractBasis) = SparseArrays.indtype(typeof(b))
+Base.keytype(b::AbstractBasis) = keytype(typeof(b))
 
 """
     ImplicitBasis{T,I}
@@ -40,15 +40,21 @@ function Basis{I}(basis::AbstractVector) where {I}
 end
 
 Base.size(b::Basis) = size(b.basis)
+Base.length(b::Basis) = length(b.basis)
+Base.keys(b::Basis) = keys(b.basis)
+Base.iterate(b::Basis) = iterate(b.basis)
+Base.iterate(b::Basis, state) = iterate(b.basis, state)
 Base.IndexStyle(::Type{<:Basis{T,I,A}}) where {T,I,A} = Base.IndexStyle(A)
 
-Base.@propagate_inbounds Base.getindex(b::Basis{T,I}, i::I) = b.basis[i]
-Base.@propagate_inbounds Base.getindex(b::Basis{T}, g::T) where {T} = b.rbasis[g]
-
 Base.in(g, b::Basis) = haskey(b.rbasis, g)
 
+Base.@propagate_inbounds Base.getindex(b::Basis{T,I}, i::I) where {T,I} = b.basis[i]
+Base.@propagate_inbounds Base.getindex(b::Basis{T}, g::T) where {T} = b.rbasis[g]
+
 # convenience only:
-Base.@propagate_inbounds function Base.getindex(b::Basis, i::Integer)
-    idx = convert(SparseArrays.indtype(b), i)
+Base.@propagate_inbounds function Base.getindex(b::Basis{T,I}, i::Integer) where {T,I<:Integer}
+    idx = convert(keytype(b), i)
     return b[idx]
 end
+# To break ambiguity
+Base.@propagate_inbounds Base.getindex(b::Basis{T,I}, i::I) where {T,I<:Integer} = b.basis[i]
diff --git a/src/coefficients.jl b/src/coefficients.jl
index 92183eb..ae1f5f8 100644
--- a/src/coefficients.jl
+++ b/src/coefficients.jl
@@ -1,5 +1,6 @@
 """
-    implements `Base.keys`, `Base.values`
+    abstract type AbstractCoefficients{V,K} end
+Implements `Base.keys`, `Base.values`.
 """
 abstract type AbstractCoefficients{V,K} end
 
@@ -8,7 +9,7 @@ struct DiracDelta{V,K} <: AbstractCoefficients{V,K}
     element::K
 end
 DiracDelta(x) = DiracDelta(1, x)
-Base.getindex(δ::DiracDelta{V,K}, i::K) =
+Base.getindex(δ::DiracDelta{V,K}, i::K) where {V,K} =
     ifelse(i == δ.element, δ.value, zero(δ.value))
 
 Base.keys(δ::DiracDelta) = (δ.element,)
@@ -22,13 +23,6 @@ end
 Base.keys(sc::SparseCoefficients) = sc.basis_elements
 Base.values(sc::SparseCoefficients) = sc.values
 
-function SparseCoefficients(
-    values::AbstractVector{V},
-    basis_elements::AbstractVector{K}
-) where {K,V}
-    return SparseCoefficients{V,K,typeof(values),typeof(basis)}(values, basis_elements)
-end
-
 function mul!(
     ms::MultiplicativeStructure,
     res::SparseCoefficients,
diff --git a/src/mstructures.jl b/src/mstructures.jl
index d7800d4..9b90729 100644
--- a/src/mstructures.jl
+++ b/src/mstructures.jl
@@ -41,7 +41,7 @@ Base.@propagate_inbounds function Base.getindex(
     mstr::LazyMStructure{I},
     g::I,
     h::I,
-)
+) where {I}
     gh = g * h
     gh in basis(mstr) || throw(ProductNotWellDefined(i, j, "$g · $h = $gh"))
     return DiracDelta(gh)
diff --git a/src/mtables.jl b/src/mtables.jl
index a391672..37fbc52 100644
--- a/src/mtables.jl
+++ b/src/mtables.jl
@@ -22,7 +22,7 @@ struct MTable{I,M<:AbstractMatrix{I},B<:AbstractBasis{I}} <: MultiplicativeStruc
     basis::B
 end
 
-function MTable(basis::AbstractBasis{V,K}; size::Tuple{Int,Int}) where {K<:Integer}
+function MTable(basis::AbstractBasis{V,K}; size::Tuple{Int,Int}) where {V,K<:Integer}
     return MTable(zeros(K, size), _star_of(basis, max(size...)), basis)
 end
 
@@ -30,7 +30,7 @@ basis(mt::MTable) = mt.basis
 Base.size(mt::MTable) = size(mt.table)
 
 Base.@propagate_inbounds __iscomputed(mt::MTable, i, j) = !iszero(mt.table[i, j])
-function Base.@propagate_inbounds Base.getindex(mt::MTable, i::Integer, j::Integer)
+Base.@propagate_inbounds function Base.getindex(mt::MTable, i::Integer, j::Integer)
     i = ifelse(i ≥ 0, i, oftype(i, mt.star_of[abs(i)]))
     j = ifelse(j ≥ 0, j, oftype(j, mt.star_of[abs(j)]))
     @boundscheck checkbounds(mt.table, i, j)
@@ -50,7 +50,7 @@ Base.@propagate_inbounds function __compute_product!(mt::MTable, i::Integer, j::
     return mt
 end
 
-function complete!(table::AbstractMatrix, basis::AbstractBasis{V,K}) where {K<:Integer}
+function complete!(table::AbstractMatrix, basis::AbstractBasis{V,K}) where {V,K<:Integer}
     Base.require_one_based_indexing(table)
     Threads.@threads for j in axes(table, 2)
         y = basis[j]
diff --git a/test/Project.toml b/test/Project.toml
new file mode 100644
index 0000000..b90c1e4
--- /dev/null
+++ b/test/Project.toml
@@ -0,0 +1,7 @@
+[deps]
+Groups = "5d8bd718-bd84-11e8-3b40-ad14f4a32557"
+GroupsCore = "d5909c97-4eac-4ecc-a3dc-fdd0858a4120"
+PermutationGroups = "8bc5a954-2dfc-11e9-10e6-cd969bffa420"
+Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
+StarAlgebras = "0c0c59c1-dc5f-42e9-9a8b-b5dc384a6cd1"
+Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
diff --git a/test/mtables.jl b/test/mtables.jl
index 97cc111..3d56b77 100644
--- a/test/mtables.jl
+++ b/test/mtables.jl
@@ -38,7 +38,7 @@ end
 @testset "MTable" begin
     b = StarAlgebras.Basis{UInt16}(words([:a, :b, :c, :d], radius=4))
     k = findfirst(w -> length(w) == 3, b) - 1
-    mstr = StarAlgebras.MTable(b, table_size=(k, k))
+    mstr = StarAlgebras.MTable(b, size=(k, k))
 
     @test_throws String StarAlgebras.basis(mstr)
 
diff --git a/test/sum_of_squares.jl b/test/sum_of_squares.jl
index 80ef114..ba19f67 100644
--- a/test/sum_of_squares.jl
+++ b/test/sum_of_squares.jl
@@ -12,7 +12,7 @@ using Groups
 
       b = StarAlgebras.Basis{UInt32}(E_R)
 
-      mstr = StarAlgebras.MTable(b, table_size=(sizes[RADIUS], sizes[RADIUS]))
+      mstr = StarAlgebras.MTable(b, size=(sizes[RADIUS], sizes[RADIUS]))
 
       RG = StarAlgebra(F, b, mstr)