diff --git a/Project.toml b/Project.toml
index 45ca7739..b7bcd4bd 100644
--- a/Project.toml
+++ b/Project.toml
@@ -12,14 +12,12 @@ Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
 SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 
 [weakdeps]
-DataInterpolations = "82cc6244-b520-54b8-b5a6-8a565e85f1d0"
 LogExpFunctions = "2ab3a3ac-af41-5b50-aa03-7779005ae688"
 NNlib = "872c559c-99b0-510c-b3b7-b6c96a88d5cd"
 NaNMath = "77ba4419-2d1f-58cd-9bb1-8ffee604a2e3"
 SpecialFunctions = "276daf66-3868-5448-9aa4-cd146d93841b"
 
 [extensions]
-SparseConnectivityTracerDataInterpolationsExt = "DataInterpolations"
 SparseConnectivityTracerLogExpFunctionsExt = "LogExpFunctions"
 SparseConnectivityTracerNNlibExt = "NNlib"
 SparseConnectivityTracerNaNMathExt = "NaNMath"
@@ -27,7 +25,6 @@ SparseConnectivityTracerSpecialFunctionsExt = "SpecialFunctions"
 
 [compat]
 ADTypes = "1"
-DataInterpolations = "8.0.1"
 DocStringExtensions = "0.9"
 FillArrays = "1"
 LinearAlgebra = "<0.0.1, 1"
diff --git a/ext/SparseConnectivityTracerDataInterpolationsExt.jl b/ext/SparseConnectivityTracerDataInterpolationsExt.jl
deleted file mode 100644
index 2f668d1b..00000000
--- a/ext/SparseConnectivityTracerDataInterpolationsExt.jl
+++ /dev/null
@@ -1,122 +0,0 @@
-# WARNING: If you are following the "Adding Overloads" guide's advice to copy an existing package extension,
-# copy another, less complicated one!
-module SparseConnectivityTracerDataInterpolationsExt
-
-using SparseConnectivityTracer: AbstractTracer, Dual, primal, tracer
-using SparseConnectivityTracer: GradientTracer, gradient_tracer_1_to_1
-using SparseConnectivityTracer: HessianTracer, hessian_tracer_1_to_1
-using FillArrays: Fill # from FillArrays.jl
-using DataInterpolations:
-    AbstractInterpolation,
-    LinearInterpolation,
-    QuadraticInterpolation,
-    LagrangeInterpolation,
-    AkimaInterpolation,
-    ConstantInterpolation,
-    QuadraticSpline,
-    CubicSpline,
-    BSplineInterpolation,
-    BSplineApprox,
-    CubicHermiteSpline,
-    # PCHIPInterpolation,
-    QuinticHermiteSpline,
-    output_size
-
-#===========#
-# Utilities #
-#===========#
-
-# Limit support to `u` begin an AbstractVector{<:Number} or AbstractMatrix{<:Number},
-# to avoid any cases where the output size is dependent on the input value.
-# https://github.com/adrhill/SparseConnectivityTracer.jl/pull/234#discussion_r2031038566
-
-function _sct_interpolate(
-        ::AbstractInterpolation,
-        uType::Type{<:AbstractVector{<:Number}},
-        t::GradientTracer,
-        is_der_1_zero,
-        is_der_2_zero,
-    )
-    return gradient_tracer_1_to_1(t, is_der_1_zero)
-end
-function _sct_interpolate(
-        ::AbstractInterpolation,
-        uType::Type{<:AbstractVector{<:Number}},
-        t::HessianTracer,
-        is_der_1_zero,
-        is_der_2_zero,
-    )
-    return hessian_tracer_1_to_1(t, is_der_1_zero, is_der_2_zero)
-end
-function _sct_interpolate(
-        interp::AbstractInterpolation,
-        uType::Type{<:AbstractMatrix{<:Number}},
-        t::GradientTracer,
-        is_der_1_zero,
-        is_der_2_zero,
-    )
-    t = gradient_tracer_1_to_1(t, is_der_1_zero)
-    N = only(output_size(interp))
-    return Fill(t, N)
-end
-function _sct_interpolate(
-        interp::AbstractInterpolation,
-        uType::Type{<:AbstractMatrix{<:Number}},
-        t::HessianTracer,
-        is_der_1_zero,
-        is_der_2_zero,
-    )
-    t = hessian_tracer_1_to_1(t, is_der_1_zero, is_der_2_zero)
-    N = only(output_size(interp))
-    return Fill(t, N)
-end
-
-#===========#
-# Overloads #
-#===========#
-
-# We assume that with the exception of ConstantInterpolation and LinearInterpolation,
-# all interpolations have a non-zero second derivative at some point in the input domain.
-
-for (I, is_der1_zero, is_der2_zero) in (
-        (:ConstantInterpolation, true, true),
-        (:LinearInterpolation, false, true),
-        (:QuadraticInterpolation, false, false),
-        (:LagrangeInterpolation, false, false),
-        (:AkimaInterpolation, false, false),
-        (:QuadraticSpline, false, false),
-        (:CubicSpline, false, false),
-        (:BSplineInterpolation, false, false),
-        (:BSplineApprox, false, false),
-        (:CubicHermiteSpline, false, false),
-        (:QuinticHermiteSpline, false, false),
-    )
-    @eval function (interp::$(I){uType})(
-            t::AbstractTracer
-        ) where {uType <: AbstractArray{<:Number}}
-        return _sct_interpolate(interp, uType, t, $is_der1_zero, $is_der2_zero)
-    end
-end
-
-# Some Interpolations require custom overloads on `Dual` due to mutation of caches.
-for I in (
-        :LagrangeInterpolation,
-        :BSplineInterpolation,
-        :BSplineApprox,
-        :CubicHermiteSpline,
-        :QuinticHermiteSpline,
-    )
-    @eval function (interp::$(I){uType})(d::Dual) where {uType <: AbstractVector}
-        p = interp(primal(d))
-        t = interp(tracer(d))
-        return Dual(p, t)
-    end
-
-    @eval function (interp::$(I){uType})(d::Dual) where {uType <: AbstractMatrix}
-        p = interp(primal(d))
-        t = interp(tracer(d))
-        return Dual.(p, t)
-    end
-end
-
-end # module SparseConnectivityTracerDataInterpolationsExt
diff --git a/test/Project.toml b/test/Project.toml
index 21e0c146..628a9889 100644
--- a/test/Project.toml
+++ b/test/Project.toml
@@ -4,7 +4,6 @@ ADTypes = "47edcb42-4c32-4615-8424-f2b9edc5f35b"
 Aqua = "4c88cf16-eb10-579e-8560-4a9242c79595"
 BenchmarkTools = "6e4b80f9-dd63-53aa-95a3-0cdb28fa8baf"
 ComponentArrays = "b0b7db55-cfe3-40fc-9ded-d10e2dbeff66"
-DataInterpolations = "82cc6244-b520-54b8-b5a6-8a565e85f1d0"
 Dates = "ade2ca70-3891-5945-98fb-dc099432e06a"
 Documenter = "e30172f5-a6a5-5a46-863b-614d45cd2de4"
 ExplicitImports = "7d51a73a-1435-4ff3-83d9-f097790105c7"
diff --git a/test/ext/test_DataInterpolations.jl b/test/ext/test_DataInterpolations.jl
deleted file mode 100644
index fc6a7307..00000000
--- a/test/ext/test_DataInterpolations.jl
+++ /dev/null
@@ -1,282 +0,0 @@
-using SparseConnectivityTracer
-using SparseConnectivityTracer: DEFAULT_GRADIENT_TRACER, DEFAULT_HESSIAN_TRACER
-using SparseConnectivityTracer: trace_input, Dual, primal
-using DataInterpolations
-using DataInterpolations: AbstractInterpolation
-
-using LinearAlgebra: I
-using Test
-
-myprimal(x) = x
-myprimal(d::Dual) = primal(d)
-
-#===========#
-# Test data #
-#===========#
-
-t = [0.0, 1.0, 2.5, 4.0, 6.0];
-t_scalar = 2.0
-t_vector = [2.0, 2.5, 3.0]
-t_range = 2:5
-test_inputs = (t_scalar, t_vector, t_range)
-
-u = sin.(t) # vector
-du = cos.(t)
-ddu = -sin.(t)
-
-#==================#
-# Test definitions #
-#==================#
-
-struct InterpolationTest{N, I <: AbstractInterpolation} # N = output dim. of interpolation
-    interp::I
-    is_der1_zero::Bool
-    is_der2_zero::Bool
-end
-function InterpolationTest(
-        interp::I; is_der1_zero = false, is_der2_zero = false
-    ) where {T, I <: AbstractInterpolation{T}}
-    sz = output_size(interp)
-    N = isempty(sz) ? 1 : only(sz)
-    return InterpolationTest{N, I}(interp, is_der1_zero, is_der2_zero)
-end
-testname(t::InterpolationTest{N}) where {N} = "$N-dim $(typeof(t.interp))"
-
-#================#
-# Jacobian Tests #
-#================#
-
-function test_jacobian(t::InterpolationTest)
-    return @testset "Jacobian" begin
-        for input in test_inputs
-            test_jacobian(t, input)
-        end
-    end
-end
-function test_jacobian(t::InterpolationTest{N}, input::Real) where {N}
-    N_IN = length(input)
-    N_OUT = N * N_IN
-    Jref = t.is_der1_zero ? zeros(N, N_IN) : ones(N, N_IN)
-
-    return @testset "input type $(typeof(input)): $N_IN inputs, $N states, $N_OUT outputs" begin
-        @testset "Global Jacobian sparsity" begin
-            J = jacobian_sparsity(t.interp, input, TracerSparsityDetector())
-            @test J ≈ Jref
-        end
-        @testset "Local Jacobian sparsity" begin
-            J = jacobian_sparsity(t.interp, input, TracerLocalSparsityDetector())
-            @test J ≈ Jref
-        end
-    end
-end
-function test_jacobian(t::InterpolationTest{1}, input::AbstractVector)
-    N = 1
-    N_IN = length(input)
-    N_OUT = N * N_IN
-    Jref = t.is_der1_zero ? zeros(N_IN, N_IN) : I(N_IN)
-
-    return @testset "input type $(typeof(input)): $N_IN inputs, $N states, $N_OUT outputs" begin
-        @testset "Global Jacobian sparsity" begin
-            J = jacobian_sparsity(x -> vec(t.interp(x)), input, TracerSparsityDetector())
-            @test J ≈ Jref
-        end
-        @testset "Local Jacobian sparsity" begin
-            J = jacobian_sparsity(
-                x -> vec(t.interp(x)), input, TracerLocalSparsityDetector()
-            )
-            @test J ≈ Jref
-        end
-    end
-end
-function test_jacobian(t::InterpolationTest{N}, input::AbstractVector) where {N}
-    N_IN = length(input)
-    N_OUT = N * N_IN
-
-    # Construct reference Jacobian
-    Jref = zeros(Bool, N_OUT, N_IN)
-    if !t.is_der1_zero
-        for (i, col) in enumerate(eachcol(Jref)) # iterate over outputs
-            i0 = 1 + N * (i - 1)
-            irange = i0:(i0 + N - 1)
-            col[irange] .= true
-        end
-    end
-
-    return @testset "input type $(typeof(input)): $N_IN inputs, $N states, $N_OUT outputs" begin
-        @testset "Global Jacobian sparsity" begin
-            J = jacobian_sparsity(x -> vec(t.interp(x)), input, TracerSparsityDetector())
-            @test J ≈ Jref
-        end
-        @testset "Local Jacobian sparsity" begin
-            J = jacobian_sparsity(
-                x -> vec(t.interp(x)), input, TracerLocalSparsityDetector()
-            )
-            @test J ≈ Jref
-        end
-    end
-end
-
-#===============#
-# Hessian Tests #
-#===============#
-
-function test_hessian(t::InterpolationTest)
-    return @testset "Hessian" begin
-        for input in test_inputs
-            test_hessian(t, input)
-        end
-    end
-end
-function test_hessian(t::InterpolationTest{1}, input::Real)
-    N = 1
-    N_IN = length(input)
-    N_OUT = N * N_IN
-    Href = t.is_der2_zero ? zeros(N_IN, N_IN) : ones(N_IN, N_IN)
-
-    return @testset "input type $(typeof(input)): $N_IN inputs, $N states, $N_OUT outputs" begin
-        @testset "Global Hessian sparsity" begin
-            H = hessian_sparsity(t.interp, input, TracerSparsityDetector())
-            @test H ≈ Href
-        end
-        @testset "Local Hessian sparsity" begin
-            H = hessian_sparsity(t.interp, input, TracerLocalSparsityDetector())
-            @test H ≈ Href
-        end
-    end
-end
-function test_hessian(t::InterpolationTest{N}, input::Real) where {N} #  N ≠ 1
-    N_IN = length(input)
-    N_OUT = N * N_IN
-    Href = t.is_der2_zero ? zeros(N_IN, N_IN) : ones(N_IN, N_IN)
-
-    return @testset "input type $(typeof(input)): $N_IN inputs, $N states, $N_OUT outputs" begin
-        @testset "Global Hessian sparsity" begin
-            H = hessian_sparsity(x -> sum(t.interp(x)), input, TracerSparsityDetector())
-            @test H ≈ Href
-        end
-        @testset "Local Hessian sparsity" begin
-            H = hessian_sparsity(
-                x -> sum(t.interp(x)), input, TracerLocalSparsityDetector()
-            )
-            @test H ≈ Href
-        end
-    end
-end
-function test_hessian(t::InterpolationTest{1}, input::AbstractVector)
-    N = 1
-    N_IN = length(input)
-    N_OUT = N * N_IN
-    Href = t.is_der2_zero ? zeros(N_IN, N_IN) : I(N_IN)
-
-    return @testset "input type $(typeof(input)): $N_IN inputs, $N states, $N_OUT outputs" begin
-        @testset "Global Hessian sparsity" begin
-            H = hessian_sparsity(x -> sum(t.interp(x)), input, TracerSparsityDetector())
-            @test H ≈ Href
-        end
-        @testset "Local Hessian sparsity" begin
-            H = hessian_sparsity(
-                x -> sum(t.interp(x)), input, TracerLocalSparsityDetector()
-            )
-            @test H ≈ Href
-        end
-    end
-end
-function test_hessian(t::InterpolationTest{N}, input::AbstractVector) where {N} #  N ≠ 1
-    N_IN = length(input)
-    N_OUT = N * N_IN
-    Href = t.is_der2_zero ? zeros(N_IN, N_IN) : I(N_IN)
-
-    return @testset "input type $(typeof(input)): $N_IN inputs, $N states, $N_OUT outputs" begin
-        @testset "Global Hessian sparsity" begin
-            H = hessian_sparsity(x -> sum(t.interp(x)), input, TracerSparsityDetector())
-            @test H ≈ Href
-        end
-        @testset "Local Hessian sparsity" begin
-            H = hessian_sparsity(
-                x -> sum(t.interp(x)), input, TracerLocalSparsityDetector()
-            )
-            @test H ≈ Href
-        end
-    end
-end
-
-function test_output(t::InterpolationTest)
-    return @testset "Output sizes and values" begin
-        @testset "input type: $(typeof(input))" for input in test_inputs
-            out_ref = t.interp(input)
-            s_ref = size(out_ref)
-
-            @testset "$T" for T in (DEFAULT_GRADIENT_TRACER, DEFAULT_HESSIAN_TRACER)
-                t_tracer = trace_input(T, input)
-                out_tracer = t.interp(t_tracer)
-                s_tracer = size(out_tracer)
-                @test s_tracer == s_ref
-            end
-            @testset "$T" for T in (
-                    Dual{eltype(input), DEFAULT_GRADIENT_TRACER},
-                    Dual{eltype(input), DEFAULT_HESSIAN_TRACER},
-                )
-                t_dual = trace_input(T, input)
-                out_dual = t.interp(t_dual)
-                s_dual = size(out_dual)
-                @test s_dual == s_ref
-                @test myprimal.(out_dual) ≈ out_ref
-            end
-        end
-    end
-end
-
-#===========#
-# Run tests #
-#===========#
-
-@testset "1D Interpolations" begin
-    @testset "$(testname(t))" for t in (
-            InterpolationTest(
-                ConstantInterpolation(u, t); is_der1_zero = true, is_der2_zero = true
-            ),
-            InterpolationTest(LinearInterpolation(u, t); is_der2_zero = true),
-            InterpolationTest(QuadraticInterpolation(u, t)),
-            InterpolationTest(LagrangeInterpolation(u, t)),
-            InterpolationTest(AkimaInterpolation(u, t)),
-            InterpolationTest(QuadraticSpline(u, t)),
-            InterpolationTest(CubicSpline(u, t)),
-            InterpolationTest(BSplineInterpolation(u, t, 3, :ArcLen, :Average)),
-            InterpolationTest(BSplineApprox(u, t, 3, 4, :ArcLen, :Average)),
-            InterpolationTest(PCHIPInterpolation(u, t)),
-            InterpolationTest(CubicHermiteSpline(du, u, t)),
-            InterpolationTest(QuinticHermiteSpline(ddu, du, u, t)),
-        )
-        test_jacobian(t)
-        test_hessian(t)
-        test_output(t)
-        yield()
-    end
-end
-
-for N in (2, 5)
-    local um = rand(N, length(t)) # matrix
-
-    @testset "$(N)D Interpolations" begin
-        @testset "$(testname(t))" for t in (
-                InterpolationTest(
-                    ConstantInterpolation(um, t); is_der1_zero = true, is_der2_zero = true
-                ),
-                InterpolationTest(LinearInterpolation(um, t); is_der2_zero = true),
-                InterpolationTest(QuadraticInterpolation(um, t)),
-                InterpolationTest(LagrangeInterpolation(um, t)),
-                ## The following interpolations appear to not be supported on N dimensions as of DataInterpolations v6.2.0:
-                # InterpolationTest(AkimaInterpolation(um, t)),
-                # InterpolationTest(BSplineApprox(um, t, 3, 4, :ArcLen, :Average)),
-                # InterpolationTest(QuadraticSpline(um, t)),
-                # InterpolationTest(CubicSpline(um, t)),
-                # InterpolationTest(BSplineInterpolation(um, t, 3, :ArcLen, :Average)),
-                # InterpolationTest(PCHIPInterpolation(um, t)),
-            )
-            test_jacobian(t)
-            test_hessian(t)
-            test_output(t)
-            yield()
-        end
-    end
-end
diff --git a/test/linting.jl b/test/linting.jl
index 485a6d21..1dd4405c 100644
--- a/test/linting.jl
+++ b/test/linting.jl
@@ -6,7 +6,6 @@ using JET: JET
 using ExplicitImports: ExplicitImports
 
 # Load package extensions so they get tested by ExplicitImports.jl
-using DataInterpolations: DataInterpolations
 using NaNMath: NaNMath
 using NNlib: NNlib
 using SpecialFunctions: SpecialFunctions
diff --git a/test/runtests.jl b/test/runtests.jl
index fec7b01a..1ff7f202 100644
--- a/test/runtests.jl
+++ b/test/runtests.jl
@@ -78,13 +78,6 @@ GROUP = get(ENV, "JULIA_SCT_TEST_GROUP", "Core")
                     include("ext/test_$ext.jl")
                 end
             end
-            # Some extensions are only loaded in newer Julia releases
-            for ext in (:DataInterpolations,)
-                @testset "$ext" begin
-                    @info "...$ext"
-                    include("ext/test_$ext.jl")
-                end
-            end
         end
     end