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diff --git a/source/blender/blenlib/BLI_generic_array.hh b/source/blender/blenlib/BLI_generic_array.hh
new file mode 100644
index 00000000000..e1b6b29874a
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+++ b/source/blender/blenlib/BLI_generic_array.hh
@@ -0,0 +1,255 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+
+#pragma once
+
+/** \file
+ * \ingroup bli
+ *
+ * This is a generic counterpart to #blender::Array, used when the type is not known at runtime.
+ *
+ * `GArray` should generally only be used for passing data around in dynamic contexts.
+ * It does not support a few things that #blender::Array supports:
+ *  - Small object optimization / inline buffer.
+ *  - Exception safety and various more specific constructors.
+ */
+
+#include "BLI_allocator.hh"
+#include "BLI_cpp_type.hh"
+#include "BLI_generic_span.hh"
+
+namespace blender {
+
+template<
+    /**
+     * The allocator used by this array. Should rarely be changed, except when you don't want that
+     * MEM_* functions are used internally.
+     */
+    typename Allocator = GuardedAllocator>
+class GArray {
+ protected:
+  /** The type of the data in the array, will be null after the array is default constructed,
+   * but a value should be assigned before any other interaction with the array. */
+  const CPPType *type_ = nullptr;
+  void *data_ = nullptr;
+  int64_t size_ = 0;
+
+  Allocator allocator_;
+
+ public:
+  /**
+   * The default constructor creates an empty array, the only situation in which the type is
+   * allowed to be null. This default constructor exists so `GArray` can be used in containers,
+   * but the type should be supplied before doing anything else to the array.
+   */
+  GArray(Allocator allocator = {}) noexcept : allocator_(allocator)
+  {
+  }
+
+  GArray(NoExceptConstructor, Allocator allocator = {}) noexcept : GArray(allocator)
+  {
+  }
+
+  /**
+   * Create and allocate a new array, with elements default constructed
+   * (which does not do anything for trivial types).
+   */
+  GArray(const CPPType &type, int64_t size, Allocator allocator = {}) : GArray(type, allocator)
+  {
+    BLI_assert(size >= 0);
+    size_ = size;
+    data_ = this->allocate(size_);
+    type_->default_construct_n(data_, size_);
+  }
+
+  /**
+   * Create an empty array with just a type.
+   */
+  GArray(const CPPType &type, Allocator allocator = {}) : GArray(allocator)
+  {
+    type_ = &type;
+  }
+
+  /**
+   * Take ownership of a buffer with a provided size. The buffer should be
+   * allocated with the same allocator provided to the constructor.
+   */
+  GArray(const CPPType &type, void *buffer, int64_t size, Allocator allocator = {})
+      : GArray(type, allocator)
+  {
+    BLI_assert(size >= 0);
+    BLI_assert(buffer != nullptr || size == 0);
+    BLI_assert(type_->pointer_has_valid_alignment(buffer));
+
+    data_ = buffer;
+    size_ = size;
+  }
+
+  /**
+   * Create an array by copying values from a generic span.
+   */
+  GArray(const GSpan span, Allocator allocator = {}) : GArray(span.type(), span.size(), allocator)
+  {
+    if (span.data() != nullptr) {
+      BLI_assert(span.size() != 0);
+      /* Use copy assign rather than construct since the memory is already initialized. */
+      type_->copy_assign_n(span.data(), data_, size_);
+    }
+  }
+
+  /**
+   * Create an array by copying values from another generic array.
+   */
+  GArray(const GArray &other) : GArray(other.as_span(), other.allocator())
+  {
+  }
+
+  /**
+   * Create an array by taking ownership of another array's data, clearing the data in the other.
+   */
+  GArray(GArray &&other) : GArray(other.type(), other.data(), other.size(), other.allocator())
+  {
+    other.data_ = nullptr;
+    other.size_ = 0;
+  }
+
+  ~GArray()
+  {
+    if (data_ != nullptr) {
+      type_->destruct_n(data_, size_);
+      this->deallocate(data_);
+    }
+  }
+
+  GArray &operator=(const GArray &other)
+  {
+    return copy_assign_container(*this, other);
+  }
+
+  GArray &operator=(GArray &&other)
+  {
+    return move_assign_container(*this, std::move(other));
+  }
+
+  const CPPType &type() const
+  {
+    BLI_assert(type_ != nullptr);
+    return *type_;
+  }
+
+  bool is_empty() const
+  {
+    return size_ == 0;
+  }
+
+  /**
+   * Return the number of elements in the array (not the size in bytes).
+   */
+  int64_t size() const
+  {
+    return size_;
+  }
+
+  /**
+   * Get a pointer to the beginning of the array.
+   */
+  const void *data() const
+  {
+    return data_;
+  }
+  void *data()
+  {
+    return data_;
+  }
+
+  const void *operator[](int64_t index) const
+  {
+    BLI_assert(index < size_);
+    return POINTER_OFFSET(data_, type_->size() * index);
+  }
+
+  void *operator[](int64_t index)
+  {
+    BLI_assert(index < size_);
+    return POINTER_OFFSET(data_, type_->size() * index);
+  }
+
+  operator GSpan() const
+  {
+    BLI_assert(type_ != nullptr);
+    return GSpan(*type_, data_, size_);
+  }
+
+  operator GMutableSpan()
+  {
+    BLI_assert(type_ != nullptr);
+    return GMutableSpan(*type_, data_, size_);
+  }
+
+  GSpan as_span() const
+  {
+    return *this;
+  }
+
+  GMutableSpan as_mutable_span()
+  {
+    return *this;
+  }
+
+  /**
+   * Access the allocator used by this array.
+   */
+  Allocator &allocator()
+  {
+    return allocator_;
+  }
+  const Allocator &allocator() const
+  {
+    return allocator_;
+  }
+
+  /**
+   * Destruct values and create a new array of the given size. The values in the new array are
+   * default constructed.
+   */
+  void reinitialize(const int64_t new_size)
+  {
+    BLI_assert(new_size >= 0);
+    int64_t old_size = size_;
+
+    type_->destruct_n(data_, size_);
+    size_ = 0;
+
+    if (new_size <= old_size) {
+      type_->default_construct_n(data_, new_size);
+    }
+    else {
+      void *new_data = this->allocate(new_size);
+      try {
+        type_->default_construct_n(new_data, new_size);
+      }
+      catch (...) {
+        this->deallocate(new_data);
+        throw;
+      }
+      this->deallocate(data_);
+      data_ = new_data;
+    }
+
+    size_ = new_size;
+  }
+
+ private:
+  void *allocate(int64_t size)
+  {
+    const int64_t item_size = type_->size();
+    const int64_t alignment = type_->alignment();
+    return allocator_.allocate(static_cast<size_t>(size) * item_size, alignment, AT);
+  }
+
+  void deallocate(void *ptr)
+  {
+    allocator_.deallocate(ptr);
+  }
+};
+
+}  // namespace blender