diff --git a/.github/workflows/CI.yml b/.github/workflows/CI.yml
index fb93af3..5573dc2 100644
--- a/.github/workflows/CI.yml
+++ b/.github/workflows/CI.yml
@@ -30,11 +30,6 @@ jobs:
           - Core
           - Benchmarks
           - NLPModels
-        exclude: # TODO: remove once LTS is not 1.6
-          - version: 'lts'
-            group: NLPModels
-          - version: 'lts'
-            group: Benchmarks
     steps:
       - uses: actions/checkout@v4
       - uses: julia-actions/setup-julia@v2
diff --git a/Project.toml b/Project.toml
index 2c20b86..a2f0868 100644
--- a/Project.toml
+++ b/Project.toml
@@ -1,7 +1,7 @@
 name = "SparseConnectivityTracer"
 uuid = "9f842d2f-2579-4b1d-911e-f412cf18a3f5"
 authors = ["Adrian Hill <gh@adrianhill.de>"]
-version = "0.6.6"
+version = "0.6.7-DEV"
 
 [deps]
 ADTypes = "47edcb42-4c32-4615-8424-f2b9edc5f35b"
@@ -9,7 +9,6 @@ DocStringExtensions = "ffbed154-4ef7-542d-bbb7-c09d3a79fcae"
 FillArrays = "1a297f60-69ca-5386-bcde-b61e274b549b"
 LinearAlgebra = "37e2e46d-f89d-539d-b4ee-838fcccc9c8e"
 Random = "9a3f8284-a2c9-5f02-9a11-845980a1fd5c"
-Requires = "ae029012-a4dd-5104-9daa-d747884805df"
 SparseArrays = "2f01184e-e22b-5df5-ae63-d93ebab69eaf"
 
 [weakdeps]
@@ -36,14 +35,6 @@ LogExpFunctions = "0.3.28"
 NNlib = "0.8, 0.9"
 NaNMath = "1"
 Random = "<0.0.1, 1"
-Requires = "1.3"
 SparseArrays = "<0.0.1, 1"
 SpecialFunctions = "2.4"
-julia = "1.6"
-
-[extras]
-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"
+julia = "1.10"
diff --git a/ext/SparseConnectivityTracerDataInterpolationsExt.jl b/ext/SparseConnectivityTracerDataInterpolationsExt.jl
index aaa2cb9..bbf4446 100644
--- a/ext/SparseConnectivityTracerDataInterpolationsExt.jl
+++ b/ext/SparseConnectivityTracerDataInterpolationsExt.jl
@@ -2,43 +2,23 @@
 # copy another, less complicated one!
 module SparseConnectivityTracerDataInterpolationsExt
 
-if isdefined(Base, :get_extension)
-    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
-    import DataInterpolations:
-        LinearInterpolation,
-        QuadraticInterpolation,
-        LagrangeInterpolation,
-        AkimaInterpolation,
-        ConstantInterpolation,
-        QuadraticSpline,
-        CubicSpline,
-        BSplineInterpolation,
-        BSplineApprox,
-        CubicHermiteSpline,
-        # PCHIPInterpolation,
-        QuinticHermiteSpline
-else
-    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
-    import ..DataInterpolations:
-        LinearInterpolation,
-        QuadraticInterpolation,
-        LagrangeInterpolation,
-        AkimaInterpolation,
-        ConstantInterpolation,
-        QuadraticSpline,
-        CubicSpline,
-        BSplineInterpolation,
-        BSplineApprox,
-        CubicHermiteSpline,
-        # PCHIPInterpolation,
-        QuinticHermiteSpline
-end
+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
+import DataInterpolations:
+    LinearInterpolation,
+    QuadraticInterpolation,
+    LagrangeInterpolation,
+    AkimaInterpolation,
+    ConstantInterpolation,
+    QuadraticSpline,
+    CubicSpline,
+    BSplineInterpolation,
+    BSplineApprox,
+    CubicHermiteSpline,
+    # PCHIPInterpolation,
+    QuinticHermiteSpline
 
 #========================#
 # General interpolations #
diff --git a/ext/SparseConnectivityTracerLogExpFunctionsExt.jl b/ext/SparseConnectivityTracerLogExpFunctionsExt.jl
index e079803..57d6247 100644
--- a/ext/SparseConnectivityTracerLogExpFunctionsExt.jl
+++ b/ext/SparseConnectivityTracerLogExpFunctionsExt.jl
@@ -1,62 +1,32 @@
 module SparseConnectivityTracerLogExpFunctionsExt
 
-if isdefined(Base, :get_extension)
-    import SparseConnectivityTracer as SCT
-    using LogExpFunctions:
-        LogExpFunctions,
-        cexpexp,
-        cloglog,
-        log1mexp,
-        log1mlogistic,
-        log1pexp,
-        log1pmx,
-        log1psq,
-        log2mexp,
-        logabssinh,
-        logaddexp,
-        logcosh,
-        logexpm1,
-        logistic,
-        logit,
-        logit1mexp,
-        logitexp,
-        loglogistic,
-        logmxp1,
-        logsubexp,
-        xexpx,
-        xexpy,
-        xlog1py,
-        xlogx,
-        xlogy
-else
-    import ..SparseConnectivityTracer as SCT
-    using ..LogExpFunctions:
-        LogExpFunctions,
-        cexpexp,
-        cloglog,
-        log1mexp,
-        log1mlogistic,
-        log1pexp,
-        log1pmx,
-        log1psq,
-        log2mexp,
-        logabssinh,
-        logaddexp,
-        logcosh,
-        logexpm1,
-        logistic,
-        logit,
-        logit1mexp,
-        logitexp,
-        loglogistic,
-        logmxp1,
-        logsubexp,
-        xexpx,
-        xexpy,
-        xlog1py,
-        xlogx,
-        xlogy
-end
+import SparseConnectivityTracer as SCT
+using LogExpFunctions:
+    LogExpFunctions,
+    cexpexp,
+    cloglog,
+    log1mexp,
+    log1mlogistic,
+    log1pexp,
+    log1pmx,
+    log1psq,
+    log2mexp,
+    logabssinh,
+    logaddexp,
+    logcosh,
+    logexpm1,
+    logistic,
+    logit,
+    logit1mexp,
+    logitexp,
+    loglogistic,
+    logmxp1,
+    logsubexp,
+    xexpx,
+    xexpy,
+    xlog1py,
+    xlogx,
+    xlogy
 
 ## 1-to-1 functions
 
diff --git a/ext/SparseConnectivityTracerNNlibExt.jl b/ext/SparseConnectivityTracerNNlibExt.jl
index b9a8a43..0edef0e 100644
--- a/ext/SparseConnectivityTracerNNlibExt.jl
+++ b/ext/SparseConnectivityTracerNNlibExt.jl
@@ -2,61 +2,32 @@
 # Parametric activation functions with two or more arguments are ignored.
 module SparseConnectivityTracerNNlibExt
 
-if isdefined(Base, :get_extension)
-    import SparseConnectivityTracer as SCT
-    using NNlib:
-        NNlib,
-        celu,
-        elu,
-        gelu,
-        hardswish,
-        hardtanh,
-        hardσ,
-        leakyrelu,
-        lisht,
-        logcosh,
-        logσ,
-        mish,
-        relu,
-        relu6,
-        selu,
-        sigmoid_fast,
-        softplus,
-        softshrink,
-        softsign,
-        swish,
-        tanh_fast,
-        tanhshrink,
-        trelu,
-        σ
-else
-    import ..SparseConnectivityTracer as SCT
-    using ..NNlib:
-        NNlib,
-        celu,
-        elu,
-        gelu,
-        hardswish,
-        hardtanh,
-        hardσ,
-        leakyrelu,
-        lisht,
-        logcosh,
-        logσ,
-        mish,
-        relu,
-        relu6,
-        selu,
-        sigmoid_fast,
-        softplus,
-        softshrink,
-        softsign,
-        swish,
-        tanh_fast,
-        tanhshrink,
-        trelu,
-        σ
-end
+import SparseConnectivityTracer as SCT
+using NNlib:
+    NNlib,
+    celu,
+    elu,
+    gelu,
+    hardswish,
+    hardtanh,
+    hardσ,
+    leakyrelu,
+    lisht,
+    logcosh,
+    logσ,
+    mish,
+    relu,
+    relu6,
+    selu,
+    sigmoid_fast,
+    softplus,
+    softshrink,
+    softsign,
+    swish,
+    tanh_fast,
+    tanhshrink,
+    trelu,
+    σ
 
 ## 1-to-1
 
diff --git a/ext/SparseConnectivityTracerNaNMathExt.jl b/ext/SparseConnectivityTracerNaNMathExt.jl
index 9502fca..6daf89c 100644
--- a/ext/SparseConnectivityTracerNaNMathExt.jl
+++ b/ext/SparseConnectivityTracerNaNMathExt.jl
@@ -1,12 +1,7 @@
 module SparseConnectivityTracerNaNMathExt
 
-if isdefined(Base, :get_extension)
-    import SparseConnectivityTracer as SCT
-    using NaNMath: NaNMath
-else
-    import ..SparseConnectivityTracer as SCT
-    using ..NaNMath: NaNMath
-end
+import SparseConnectivityTracer as SCT
+using NaNMath: NaNMath
 
 ## 1-to-1
 
diff --git a/ext/SparseConnectivityTracerSpecialFunctionsExt.jl b/ext/SparseConnectivityTracerSpecialFunctionsExt.jl
index 42a7d81..2bdc084 100644
--- a/ext/SparseConnectivityTracerSpecialFunctionsExt.jl
+++ b/ext/SparseConnectivityTracerSpecialFunctionsExt.jl
@@ -1,100 +1,51 @@
 module SparseConnectivityTracerSpecialFunctionsExt
 
-if isdefined(Base, :get_extension)
-    import SparseConnectivityTracer as SCT
-    using SpecialFunctions:
-        SpecialFunctions,
-        airyai,
-        airyaiprime,
-        airyaiprimex,
-        airyaix,
-        airybi,
-        airybiprime,
-        airybiprimex,
-        airybix,
-        besseli,
-        besselix,
-        besselj,
-        besselj0,
-        besselj1,
-        besseljx,
-        besselk,
-        besselkx,
-        bessely,
-        bessely0,
-        bessely1,
-        besselyx,
-        beta,
-        cosint,
-        digamma,
-        ellipe,
-        ellipk,
-        erf,
-        erfc,
-        erfcinv,
-        erfcx,
-        erfinv,
-        expint,
-        expinti,
-        expintx,
-        gamma,
-        invdigamma,
-        jinc,
-        logbeta,
-        logerfc,
-        loggamma,
-        sinint,
-        sphericalbesselj,
-        sphericalbessely,
-        trigamma
-else
-    import ..SparseConnectivityTracer as SCT
-    using ..SpecialFunctions:
-        SpecialFunctions,
-        airyai,
-        airyaiprime,
-        airyaiprimex,
-        airyaix,
-        airybi,
-        airybiprime,
-        airybiprimex,
-        airybix,
-        besseli,
-        besselix,
-        besselj,
-        besselj0,
-        besselj1,
-        besseljx,
-        besselk,
-        besselkx,
-        bessely,
-        bessely0,
-        bessely1,
-        besselyx,
-        beta,
-        cosint,
-        digamma,
-        ellipe,
-        ellipk,
-        erf,
-        erfc,
-        erfcinv,
-        erfcx,
-        erfinv,
-        expint,
-        expinti,
-        expintx,
-        gamma,
-        invdigamma,
-        jinc,
-        logbeta,
-        logerfc,
-        loggamma,
-        sinint,
-        sphericalbesselj,
-        sphericalbessely,
-        trigamma
-end
+import SparseConnectivityTracer as SCT
+using SpecialFunctions:
+    SpecialFunctions,
+    airyai,
+    airyaiprime,
+    airyaiprimex,
+    airyaix,
+    airybi,
+    airybiprime,
+    airybiprimex,
+    airybix,
+    besseli,
+    besselix,
+    besselj,
+    besselj0,
+    besselj1,
+    besseljx,
+    besselk,
+    besselkx,
+    bessely,
+    bessely0,
+    bessely1,
+    besselyx,
+    beta,
+    cosint,
+    digamma,
+    ellipe,
+    ellipk,
+    erf,
+    erfc,
+    erfcinv,
+    erfcx,
+    erfinv,
+    expint,
+    expinti,
+    expintx,
+    gamma,
+    invdigamma,
+    jinc,
+    logbeta,
+    logerfc,
+    loggamma,
+    sinint,
+    sphericalbesselj,
+    sphericalbessely,
+    trigamma
 
 #=
 Complex functions are ignored.
diff --git a/src/SparseConnectivityTracer.jl b/src/SparseConnectivityTracer.jl
index b507da6..dfa0d7c 100644
--- a/src/SparseConnectivityTracer.jl
+++ b/src/SparseConnectivityTracer.jl
@@ -11,10 +11,6 @@ using FillArrays: Fill
 
 using DocStringExtensions: DocStringExtensions, TYPEDEF, TYPEDFIELDS
 
-if !isdefined(Base, :get_extension)
-    using Requires
-end
-
 include("settypes/duplicatevector.jl")
 include("settypes/recursiveset.jl")
 include("settypes/sortedvector.jl")
@@ -42,22 +38,4 @@ export TracerLocalSparsityDetector
 # Reexport ADTypes interface
 export jacobian_sparsity, hessian_sparsity
 
-function __init__()
-    @static if !isdefined(Base, :get_extension)
-        @require LogExpFunctions = "2ab3a3ac-af41-5b50-aa03-7779005ae688" include(
-            "../ext/SparseConnectivityTracerLogExpFunctionsExt.jl"
-        )
-        @require NaNMath = "77ba4419-2d1f-58cd-9bb1-8ffee604a2e3" include(
-            "../ext/SparseConnectivityTracerNaNMathExt.jl"
-        )
-        @require NNlib = "872c559c-99b0-510c-b3b7-b6c96a88d5cd" include(
-            "../ext/SparseConnectivityTracerNNlibExt.jl"
-        )
-        @require SpecialFunctions = "276daf66-3868-5448-9aa4-cd146d93841b" include(
-            "../ext/SparseConnectivityTracerSpecialFunctionsExt.jl"
-        )
-        # NOTE: DataInterpolations extension is not loaded on Julia <1.10
-    end
-end
-
 end # module
diff --git a/test/linting.jl b/test/linting.jl
index 4ae6a26..cc0d951 100644
--- a/test/linting.jl
+++ b/test/linting.jl
@@ -23,7 +23,6 @@ end
         SparseConnectivityTracer;
         ambiguities=false,
         deps_compat=(check_extras=false,),
-        stale_deps=(ignore=[:Requires],),
         persistent_tasks=false,
     )
 end
diff --git a/test/test_arrays.jl b/test/test_arrays.jl
index 3f069d8..095f304 100644
--- a/test/test_arrays.jl
+++ b/test/test_arrays.jl
@@ -311,14 +311,11 @@ end
             testJ1(SpdiagmifyInput(exp), v)
             testH1(SpdiagmifyInput(exp), v)
 
-            if VERSION >= v"1.10"
-                # issue with custom _mapreducezeros in SparseArrays on Julia 1.6
-                testJ0(SpdiagmifyInput(pow0), v)
-                testH0(SpdiagmifyInput(pow0), v)
+            testJ0(SpdiagmifyInput(pow0), v)
+            testH0(SpdiagmifyInput(pow0), v)
 
-                testJ1(SpdiagmifyInput(pow3), v)
-                testH1(SpdiagmifyInput(pow3), v)
-            end
+            testJ1(SpdiagmifyInput(pow3), v)
+            testH1(SpdiagmifyInput(pow3), v)
         end
     end
 
@@ -327,11 +324,9 @@ end
         testJ1(pinv, A)
         testH1(pinv, A)
     end
-    if VERSION >= v"1.9"
-        @testset "`SparseMatrixCSC` (3×4)" begin
-            testJ1(SparsifyInput(pinv), rand(3, 4))
-            testH1(SparsifyInput(pinv), rand(3, 4))
-        end
+    @testset "`SparseMatrixCSC` (3×4)" begin
+        testJ1(SparsifyInput(pinv), rand(3, 4))
+        testH1(SparsifyInput(pinv), rand(3, 4))
     end
 end