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diff --git a/source/slang/diff.meta.slang b/source/slang/diff.meta.slang
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+
+/// Modifer to mark a function for forward-mode differentiation.
+/// i.e. the compiler will automatically generate a new function
+/// that computes the jacobian-vector product of the original.
+syntax __differentiate_jvp : JVPDerivativeModifier;
+
+// Custom JVP Function reference
+__attributeTarget(FuncDecl)
+attribute_syntax [__custom_jvp(function)]   : CustomJVPAttribute;
+
+//@ public:
+
+    /// Interface to denote types as differentiable.
+    /// Allows for user-specified differential types as
+    /// well as automatic generation, for when the associated type
+    /// hasn't been declared explicitly.
+__magic_type(DifferentiableType)
+interface IDifferentiable
+{
+    associatedtype Differential;
+};
+
+    /// Pair type that serves to wrap the primal and
+    /// differential types of an arbitrary type T.
+__generic<T : IDifferentiable>
+__magic_type(DifferentialPairType)
+__intrinsic_type($(kIROp_DifferentialPairType))
+struct __DifferentialPair
+{
+
+    __intrinsic_op($(kIROp_MakeDifferentialPair))
+    __init(T _primal, T.Differential _differential);
+
+    __intrinsic_op($(kIROp_DifferentialPairGetDifferential))
+    T.Differential d();
+
+    T.Differential getDifferential()
+    {
+        return d();
+    }
+
+    __intrinsic_op($(kIROp_DifferentialPairGetPrimal))
+    T p();
+
+    T getPrimal()
+    {
+        return p();
+    }
+};
+
+// Add extensions for the standard types
+extension float : IDifferentiable
+{
+    typedef float Differential;
+}
+
+extension vector<float, 3> : IDifferentiable
+{
+    typedef vector<float, 3> Differential;
+}
+
+extension vector<float, 2> : IDifferentiable
+{
+    typedef vector<float, 2> Differential;
+}
+
+extension vector<float, 4> : IDifferentiable
+{
+    typedef vector<float, 4> Differential;
+}