diff --git a/Project.toml b/Project.toml
index 7a85171..a7c2676 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "TensorAlgebra"
 uuid = "68bd88dc-f39d-4e12-b2ca-f046b68fcc6a"
 authors = ["ITensor developers <support@itensor.org> and contributors"]
-version = "0.4.1"
+version = "0.4.2"
 
 [deps]
 ArrayLayouts = "4c555306-a7a7-4459-81d9-ec55ddd5c99a"
diff --git a/src/MatrixAlgebra.jl b/src/MatrixAlgebra.jl
index 82859cd..5eec67f 100644
--- a/src/MatrixAlgebra.jl
+++ b/src/MatrixAlgebra.jl
@@ -17,8 +17,7 @@ export eigen,
   svd,
   svd!,
   svdvals,
-  svdvals!,
-  truncerr
+  svdvals!
 
 using LinearAlgebra: LinearAlgebra, norm
 using MatrixAlgebraKit
@@ -143,43 +142,6 @@ end
 
 using MatrixAlgebraKit: MatrixAlgebraKit, TruncationStrategy
 
-struct TruncationError{T<:Real} <: TruncationStrategy
-  atol::T
-  rtol::T
-  p::Int
-end
-
-"""
-    truncerr(; atol::Real=0, rtol::Real=0, p::Int=2)
-
-Create a truncation strategy for truncating such that the error in the factorization
-is smaller than `max(atol, rtol * norm)`, where the error is determined using the `p`-norm.
-"""
-function truncerr(; atol::Real=0, rtol::Real=0, p::Int=2)
-  return TruncationError(promote(atol, rtol)..., p)
-end
-
-function MatrixAlgebraKit.findtruncated(values::AbstractVector, strategy::TruncationError)
-  Base.require_one_based_indexing(values)
-  issorted(values; rev=true) || error("Not sorted.")
-  # norm(values, p) ^ p
-  normᵖ = sum(Base.Fix2(^, strategy.p) ∘ abs, values)
-  ϵᵖ = max(strategy.atol ^ strategy.p, strategy.rtol ^ strategy.p * normᵖ)
-  if ϵᵖ ≥ normᵖ
-    return Base.OneTo(0)
-  end
-  truncerrᵖ = zero(real(eltype(values)))
-  rank = length(values)
-  for i in reverse(eachindex(values))
-    truncerrᵖ += abs(values[i]) ^ strategy.p
-    if truncerrᵖ ≥ ϵᵖ
-      rank = i
-      break
-    end
-  end
-  return Base.OneTo(rank)
-end
-
 struct TruncationDegenerate{Strategy<:TruncationStrategy,T<:Real} <: TruncationStrategy
   strategy::Strategy
   atol::T
diff --git a/test/Project.toml b/test/Project.toml
index 656853a..07bf51e 100644
--- a/test/Project.toml
+++ b/test/Project.toml
@@ -16,14 +16,14 @@ TestExtras = "5ed8adda-3752-4e41-b88a-e8b09835ee3a"
 [compat]
 Aqua = "0.8.9"
 BlockArrays = "1.6.1"
-EllipsisNotation = "1.8.0"
+EllipsisNotation = "1.8"
 LinearAlgebra = "<0.0.1, 1"
 MatrixAlgebraKit = "0.2, 0.3"
 Random = "1.10"
 SafeTestsets = "0.1"
 StableRNGs = "1.0.2"
 Suppressor = "0.2"
-TensorAlgebra = "0.4.0"
+TensorAlgebra = "0.4"
 TensorOperations = "5.1.4"
 Test = "1.10"
 TestExtras = "0.3.1"
diff --git a/test/test_exports.jl b/test/test_exports.jl
index 321164f..0c7b00b 100644
--- a/test/test_exports.jl
+++ b/test/test_exports.jl
@@ -45,7 +45,6 @@ using TensorAlgebra: TensorAlgebra
     :svd!,
     :svdvals,
     :svdvals!,
-    :truncerr,
   ]
   @test issetequal(names(TensorAlgebra.MatrixAlgebra), exports)
 end
diff --git a/test/test_matrixalgebra.jl b/test/test_matrixalgebra.jl
index 36ee71c..7feefa3 100644
--- a/test/test_matrixalgebra.jl
+++ b/test/test_matrixalgebra.jl
@@ -1,7 +1,7 @@
 using LinearAlgebra: Diagonal, I, diag, isposdef, norm
 using MatrixAlgebraKit: qr_compact, svd_trunc, truncrank
 using StableRNGs: StableRNG
-using TensorAlgebra.MatrixAlgebra: MatrixAlgebra, truncdegen, truncerr
+using TensorAlgebra.MatrixAlgebra: MatrixAlgebra, truncdegen
 using Test: @test, @testset
 
 elts = (Float32, Float64, ComplexF32, ComplexF64)
@@ -152,158 +152,6 @@ elts = (Float32, Float64, ComplexF32, ComplexF64)
     @test V' * V ≈ I
     @test MatrixAlgebra.svdvals(A) ≈ diag(S)
   end
-  @testset "Truncation" begin
-    s = Diagonal(real(elt)[1.2, 0.9, 0.3, 0.2, 0.01])
-    n = length(diag(s))
-    rng = StableRNG(123)
-    u, _ = qr_compact(randn(rng, elt, n, n); positive=true)
-    v, _ = qr_compact(randn(rng, elt, n, n); positive=true)
-    a = u * s * v
-
-    # p = 2, relative = true
-    ũ, s̃, ṽ = svd_trunc(
-      a; trunc=truncerr(; rtol=norm([0.3, 0.2, 0.01]) / norm(diag(s)) + 10eps(real(elt)))
-    )
-    @test size(ũ) == (n, 2)
-    @test size(s̃) == (2, 2)
-    @test size(ṽ) == (2, n)
-    @test norm(ũ * s̃ * ṽ - a) ≈ norm([0.3, 0.2, 0.01])
-    ũ, s̃, ṽ = svd_trunc(
-      a; trunc=truncerr(; rtol=norm([0.3, 0.2, 0.01]) / norm(diag(s)) - 10eps(real(elt)))
-    )
-    @test size(ũ) == (n, 3)
-    @test size(s̃) == (3, 3)
-    @test size(ṽ) == (3, n)
-    @test norm(ũ * s̃ * ṽ - a) ≈ norm([0.2, 0.01])
-    ũ, s̃, ṽ = svd_trunc(a; trunc=truncerr(; rtol=0))
-    @test size(ũ) == (n, n)
-    @test size(s̃) == (n, n)
-    @test size(ṽ) == (n, n)
-    @test ũ * s̃ * ṽ ≈ a
-    ũ, s̃, ṽ = svd_trunc(a; trunc=truncerr(; rtol=1))
-    @test size(ũ) == (n, 0)
-    @test size(s̃) == (0, 0)
-    @test size(ṽ) == (0, n)
-    @test norm(ũ * s̃ * ṽ) ≈ 0
-
-    # p = 2, relative = false
-    ũ, s̃, ṽ = svd_trunc(
-      a; trunc=truncerr(; atol=norm([0.3, 0.2, 0.01]) + 10eps(real(elt)))
-    )
-    @test size(ũ) == (n, 2)
-    @test size(s̃) == (2, 2)
-    @test size(ṽ) == (2, n)
-    @test norm(ũ * s̃ * ṽ - a) ≈ norm([0.3, 0.2, 0.01])
-    ũ, s̃, ṽ = svd_trunc(
-      a; trunc=truncerr(; atol=norm([0.3, 0.2, 0.01]) - 10eps(real(elt)))
-    )
-    @test size(ũ) == (n, 3)
-    @test size(s̃) == (3, 3)
-    @test size(ṽ) == (3, n)
-    @test norm(ũ * s̃ * ṽ - a) ≈ norm([0.2, 0.01])
-    ũ, s̃, ṽ = svd_trunc(a; trunc=truncerr(; atol=0))
-    @test size(ũ) == (n, n)
-    @test size(s̃) == (n, n)
-    @test size(ṽ) == (n, n)
-    @test ũ * s̃ * ṽ ≈ a
-    ũ, s̃, ṽ = svd_trunc(
-      a; trunc=truncerr(; atol=(norm(diag(s)) * (one(real(elt)) + 10eps(real(elt)))))
-    )
-    @test size(ũ) == (n, 0)
-    @test size(s̃) == (0, 0)
-    @test size(ṽ) == (0, n)
-    @test norm(ũ * s̃ * ṽ) ≈ 0
-
-    # p = 1, relative = true
-    ũ, s̃, ṽ = svd_trunc(
-      a;
-      trunc=truncerr(;
-        rtol=(norm([0.3, 0.2, 0.01], 1) / norm(diag(s), 1) + 10eps(real(elt))), p=1
-      ),
-    )
-    @test size(ũ) == (n, 2)
-    @test size(s̃) == (2, 2)
-    @test size(ṽ) == (2, n)
-    @test norm(ũ * s̃ * ṽ - a) ≈ norm([0.3, 0.2, 0.01])
-    ũ, s̃, ṽ = svd_trunc(
-      a;
-      trunc=truncerr(;
-        rtol=(norm([0.3, 0.2, 0.01], 1) / norm(diag(s), 1) - 10eps(real(elt))), p=1
-      ),
-    )
-    @test size(ũ) == (n, 3)
-    @test size(s̃) == (3, 3)
-    @test size(ṽ) == (3, n)
-    @test norm(ũ * s̃ * ṽ - a) ≈ norm([0.2, 0.01])
-    ũ, s̃, ṽ = svd_trunc(a; trunc=truncerr(; rtol=0, p=1))
-    @test size(ũ) == (n, n)
-    @test size(s̃) == (n, n)
-    @test size(ṽ) == (n, n)
-    @test ũ * s̃ * ṽ ≈ a
-    ũ, s̃, ṽ = svd_trunc(a; trunc=truncerr(; rtol=1, p=1))
-    @test size(ũ) == (n, 0)
-    @test size(s̃) == (0, 0)
-    @test size(ṽ) == (0, n)
-    @test norm(ũ * s̃ * ṽ) ≈ 0
-
-    # p = 1, relative = false
-    ũ, s̃, ṽ = svd_trunc(
-      a; trunc=truncerr(; atol=(norm([0.3, 0.2, 0.01], 1) + 10eps(real(elt))), p=1)
-    )
-    @test size(ũ) == (n, 2)
-    @test size(s̃) == (2, 2)
-    @test size(ṽ) == (2, n)
-    @test norm(ũ * s̃ * ṽ - a) ≈ norm([0.3, 0.2, 0.01])
-    ũ, s̃, ṽ = svd_trunc(
-      a; trunc=truncerr(; atol=(norm([0.3, 0.2, 0.01], 1) - 10eps(real(elt))), p=1)
-    )
-    @test size(ũ) == (n, 3)
-    @test size(s̃) == (3, 3)
-    @test size(ṽ) == (3, n)
-    @test norm(ũ * s̃ * ṽ - a) ≈ norm([0.2, 0.01])
-    ũ, s̃, ṽ = svd_trunc(a; trunc=truncerr(; atol=0, p=1))
-    @test size(ũ) == (n, n)
-    @test size(s̃) == (n, n)
-    @test size(ṽ) == (n, n)
-    @test ũ * s̃ * ṽ ≈ a
-    ũ, s̃, ṽ = svd_trunc(
-      a;
-      trunc=truncerr(; atol=(norm(diag(s), 1) * (one(real(elt)) + 10eps(real(elt)))), p=1),
-    )
-    @test size(ũ) == (n, 0)
-    @test size(s̃) == (0, 0)
-    @test size(ṽ) == (0, n)
-    @test norm(ũ * s̃ * ṽ) ≈ 0
-
-    # Specifying both `atol` and `rtol`.
-    s = Diagonal(real(elt)[0.1, 0.01, 0.001])
-    n = length(diag(s))
-    rng = StableRNG(123)
-    u, _ = qr_compact(randn(rng, elt, n, n); positive=true)
-    v, _ = qr_compact(randn(rng, elt, n, n); positive=true)
-    a = u * s * v
-
-    ũ, s̃, ṽ = svd_trunc(a; trunc=truncerr(; rtol=0.002))
-    @test size(ũ) == (n, n)
-    @test size(s̃) == (n, n)
-    @test size(ṽ) == (n, n)
-    @test ũ * s̃ * ṽ ≈ a
-    @test ũ * s̃ * ṽ ≈ a rtol = 0.002
-
-    ũ, s̃, ṽ = svd_trunc(a; trunc=truncerr(; atol=0.002))
-    @test size(ũ) == (n, 2)
-    @test size(s̃) == (2, 2)
-    @test size(ṽ) == (2, n)
-    @test norm(ũ * s̃ * ṽ - a) ≈ norm([0.001])
-    @test ũ * s̃ * ṽ ≈ a atol = 0.002
-
-    ũ, s̃, ṽ = svd_trunc(a; trunc=truncerr(; atol=0.002, rtol=0.002))
-    @test size(ũ) == (n, 2)
-    @test size(s̃) == (2, 2)
-    @test size(ṽ) == (2, n)
-    @test norm(ũ * s̃ * ṽ - a) ≈ norm([0.001])
-    @test ũ * s̃ * ṽ ≈ a atol = 0.002 rtol = 0.002
-  end
   @testset "Truncate degenerate" begin
     s = Diagonal(real(elt)[2.0, 0.32, 0.3, 0.29, 0.01, 0.01])
     n = length(diag(s))