diff --git a/Project.toml b/Project.toml
index e85ef7e..250c673 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,33 +1,21 @@
 name = "ITensorBase"
 uuid = "4795dd04-0d67-49bb-8f44-b89c448a1dc7"
 authors = ["ITensor developers <support@itensor.org> and contributors"]
-version = "0.4.4"
+version = "0.4.5"
 
 [deps]
 Accessors = "7d9f7c33-5ae7-4f3b-8dc6-eff91059b697"
 ConstructionBase = "187b0558-2788-49d3-abe0-74a17ed4e7c9"
-FillArrays = "1a297f60-69ca-5386-bcde-b61e274b549b"
-LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
-MapBroadcast = "ebd9b9da-f48d-417c-9660-449667d60261"
 NamedDimsArrays = "60cbd0c0-df58-4cb7-918c-6f5607b73fde"
 Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
 TensorAlgebra = "68bd88dc-f39d-4e12-b2ca-f046b68fcc6a"
-UnallocatedArrays = "43c9e47c-e622-40fb-bf18-a09fc8c466b6"
-UnspecifiedTypes = "42b3faec-625b-4613-8ddc-352bf9672b8d"
-VectorInterface = "409d34a3-91d5-4945-b6ec-7529ddf182d8"
 
 [compat]
 Accessors = "0.1.39"
 ConstructionBase = "1.6.0"
-FillArrays = "1.13"
-LinearAlgebra = "1.10"
-MapBroadcast = "0.1.5"
 NamedDimsArrays = "0.13"
 Random = "1.10"
 TensorAlgebra = "0.3, 0.4, 0.5, 0.6"
-UnallocatedArrays = "0.1.1"
-UnspecifiedTypes = "0.1.1"
-VectorInterface = "0.5"
 julia = "1.10"
 
 [workspace]
diff --git a/README.md b/README.md
index f89d849..3e79771 100644
--- a/README.md
+++ b/README.md
@@ -63,15 +63,6 @@ q, r = qr(a, (i,))
 @test q * r ≈ a
 ````
 
-Automatic allocation
-
-````julia
-a = ITensor(i, j)
-a[j[1], i[2]] = 1 + 2im
-eltype(a) == Complex{Int}
-@test a[i[2], j[1]] == 1 + 2im
-````
-
 ---
 
 *This page was generated using [Literate.jl](https://github.com/fredrikekre/Literate.jl).*
diff --git a/examples/README.jl b/examples/README.jl
index 27e2dd2..9a6e235 100644
--- a/examples/README.jl
+++ b/examples/README.jl
@@ -62,9 +62,3 @@ d = a + a′
 @test a ≈ aligndims(a, (j, i))
 q, r = qr(a, (i,))
 @test q * r ≈ a
-
-# Automatic allocation
-a = ITensor(i, j)
-a[j[1], i[2]] = 1 + 2im
-eltype(a) == Complex{Int}
-@test a[i[2], j[1]] == 1 + 2im
diff --git a/src/abstractitensor.jl b/src/abstractitensor.jl
index 8757331..f19771d 100644
--- a/src/abstractitensor.jl
+++ b/src/abstractitensor.jl
@@ -1,4 +1,3 @@
-using MapBroadcast: Mapped
 using NamedDimsArrays: NamedDimsArrays, AbstractNamedDimsArray, NamedDimsArray, denamed,
     dimnames, inds, mapinds
 
@@ -8,52 +7,7 @@ NamedDimsArrays.nameddimsconstructor(::Type{<:IndexName}) = ITensor
 
 Base.ndims(::Type{<:AbstractITensor}) = Any
 
-using FillArrays: Zeros
-using UnallocatedArrays: UnallocatedZeros, allocate
-using UnspecifiedTypes: UnspecifiedZero
-
-# TODO: Make this more general, maybe with traits `is_unallocated`
-# and `is_eltype_unspecified`.
-function specify_eltype(a::Zeros{UnspecifiedZero}, elt::Type)
-    return Zeros{elt}(axes(a))
-end
-specify_eltype(a::AbstractArray, elt::Type) = a
-
-# TODO: Use `adapt` to reach down into the storage.
-function specify_eltype!(a::AbstractITensor, elt::Type)
-    setdenamed!(a, specify_eltype(denamed(a), elt))
-    return a
-end
-
-# Assume it is allocated.
-allocate!(a::AbstractArray) = a
-
-# TODO: Use `adapt` to reach down into the storage.
-function allocate!(a::AbstractITensor)
-    setdenamed!(a, allocate(denamed(a)))
-    return a
-end
-
-unallocatable(a::AbstractITensor) = NamedDimsArray(a)
-
-function setindex_allocatable!(a::AbstractArray, value, I...)
-    allocate!(specify_eltype!(a, typeof(value)))
-    # TODO: Maybe use `@interface interface(a) a[I...] = value`?
-    unallocatable(a)[I...] = value
-    return a
-end
-
-# TODO: Combine these by using `Base.to_indices`.
-function Base.setindex!(a::AbstractITensor, value, I::Int...)
-    setindex_allocatable!(a, value, I...)
-    return a
-end
-function Base.setindex!(a::AbstractITensor, value, I::AbstractNamedInteger...)
-    setindex_allocatable!(a, value, I...)
-    return a
-end
-
-mutable struct ITensor <: AbstractITensor
+struct ITensor <: AbstractITensor
     parent::AbstractArray
     inds
     function ITensor(parent::AbstractArray, dims)
@@ -72,22 +26,3 @@ end
 function ITensor(parent::AbstractArray)
     return ITensor(parent, ())
 end
-
-using Accessors: @set
-setdenamed(a::ITensor, denamed) = (@set a.parent = denamed)
-setdenamed!(a::ITensor, denamed) = (a.parent = denamed)
-
-function ITensor(elt::Type, I1::Index, I_rest::Index...)
-    I = (I1, I_rest...)
-    # TODO: Use `FillArrays.Zeros`.
-    return ITensor(zeros(elt, length.(denamed.(I))...), I)
-end
-
-function ITensor(I1::Index, I_rest::Index...)
-    I = (I1, I_rest...)
-    return ITensor(Zeros{UnspecifiedZero}(length.(denamed.(I))...), I)
-end
-
-function ITensor()
-    return ITensor(Zeros{UnspecifiedZero}(), ())
-end