diff --git a/sandbox/main.zig b/sandbox/main.zig
index 03a23f0..69c9cd3 100644
--- a/sandbox/main.zig
+++ b/sandbox/main.zig
@@ -35,12 +35,12 @@ pub fn main() !void {
                 };
 
                 try rt.writeBuiltIn(std.mem.asBytes(&global_invocation_indices), .GlobalInvocationId);
-                try rt.writeDescriptorSet(allocator, std.mem.asBytes(&ssbo), 0, 0);
+                try rt.writeDescriptorSet(std.mem.asBytes(&ssbo), 0, 0);
                 rt.callEntryPoint(allocator, entry) catch |err| switch (err) {
                     spv.Runtime.RuntimeError.OutOfBounds => continue,
                     else => return err,
                 };
-                try rt.readDescriptorSet(std.mem.asBytes(&ssbo), 0, 0);
+                try rt.flushDescriptorSets(allocator);
             }
         }
 
diff --git a/src/Result.zig b/src/Result.zig
index 4d01646..b8358ec 100644
--- a/src/Result.zig
+++ b/src/Result.zig
@@ -113,28 +113,33 @@ pub const Value = union(Type) {
     Vector2u32: Vec2u32,
     Matrix: []Value,
     Array: []Value,
-    RuntimeArray: ?[]Value,
+    RuntimeArray: struct {
+        type_word: SpvWord,
+        data: []u8,
+    },
     Structure: []Value,
     Function: noreturn,
     Image: struct {},
     Sampler: struct {},
     SampledImage: struct {},
-    Pointer: union(enum) {
-        common: *Value,
-        f32_ptr: *f32,
-        i32_ptr: *i32, //< For vector specializations
-        u32_ptr: *u32,
+    Pointer: struct {
+        ptr: union(enum) {
+            common: *Value,
+            f32_ptr: *f32,
+            i32_ptr: *i32, //< For vector specializations
+            u32_ptr: *u32,
+        },
+        runtime_array_window: ?[]u8 = null,
     },
 
     pub inline fn getCompositeDataOrNull(self: *const Value) ?[]Value {
         return switch (self.*) {
             .Vector, .Matrix, .Array, .Structure => |v| v,
-            .RuntimeArray => |v| v,
             else => null,
         };
     }
 
-    fn init(allocator: std.mem.Allocator, results: []const Self, target: SpvWord) RuntimeError!Value {
+    pub fn init(allocator: std.mem.Allocator, results: []const Self, target: SpvWord) RuntimeError!Value {
         const resolved = results[target].resolveType(results);
         const member_count = resolved.getMemberCounts();
 
@@ -194,7 +199,12 @@ pub const Value = union(Type) {
                     }
                     break :blk self;
                 },
-                .RuntimeArray => .{ .RuntimeArray = null },
+                .RuntimeArray => |a| .{
+                    .RuntimeArray = .{
+                        .type_word = a.components_type_word,
+                        .data = &.{},
+                    },
+                },
                 else => unreachable,
             },
             else => unreachable,
@@ -225,17 +235,6 @@ pub const Value = union(Type) {
                     break :blk values;
                 },
             },
-            .RuntimeArray => |opt_a| .{
-                .RuntimeArray = blk: {
-                    if (opt_a) |a| {
-                        const values = allocator.dupe(Value, a) catch return RuntimeError.OutOfMemory;
-                        for (values, a) |*new_value, value| new_value.* = try value.dupe(allocator);
-                        break :blk values;
-                    } else {
-                        break :blk null;
-                    }
-                },
-            },
             .Structure => |s| .{
                 .Structure = blk: {
                     const values = allocator.dupe(Value, s) catch return RuntimeError.OutOfMemory;
@@ -247,16 +246,244 @@ pub const Value = union(Type) {
         };
     }
 
+    pub fn read(self: *const Value, output: []u8) RuntimeError!usize {
+        switch (self.*) {
+            .Bool => |b| {
+                output[0] = if (b == true) 1 else 0;
+                return 1;
+            },
+            .Int => |i| {
+                switch (i.bit_count) {
+                    8 => output[0] = @bitCast(i.value.uint8),
+                    16 => std.mem.copyForwards(u8, output[0..], std.mem.asBytes(&i.value.uint16)),
+                    32 => std.mem.copyForwards(u8, output[0..], std.mem.asBytes(&i.value.uint32)),
+                    64 => std.mem.copyForwards(u8, output[0..], std.mem.asBytes(&i.value.uint64)),
+                    else => return RuntimeError.InvalidValueType,
+                }
+                return @divExact(i.bit_count, 8);
+            },
+            .Float => |f| {
+                switch (f.bit_count) {
+                    16 => std.mem.copyForwards(u8, output[0..], std.mem.asBytes(&f.value.float16)),
+                    32 => std.mem.copyForwards(u8, output[0..], std.mem.asBytes(&f.value.float32)),
+                    64 => std.mem.copyForwards(u8, output[0..], std.mem.asBytes(&f.value.float64)),
+                    else => return RuntimeError.InvalidValueType,
+                }
+                return @divExact(f.bit_count, 8);
+            },
+            .Vector4f32 => |vec| {
+                inline for (0..4) |i| {
+                    std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
+                }
+                return 4 * 4;
+            },
+            .Vector3f32 => |vec| {
+                inline for (0..3) |i| {
+                    std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
+                }
+                return 3 * 4;
+            },
+            .Vector2f32 => |vec| {
+                inline for (0..2) |i| {
+                    std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
+                }
+                return 2 * 4;
+            },
+            .Vector4i32 => |vec| {
+                inline for (0..4) |i| {
+                    std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
+                }
+                return 4 * 4;
+            },
+            .Vector3i32 => |vec| {
+                inline for (0..3) |i| {
+                    std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
+                }
+                return 3 * 4;
+            },
+            .Vector2i32 => |vec| {
+                inline for (0..2) |i| {
+                    std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
+                }
+                return 2 * 4;
+            },
+            .Vector4u32 => |vec| {
+                inline for (0..4) |i| {
+                    std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
+                }
+                return 4 * 4;
+            },
+            .Vector3u32 => |vec| {
+                inline for (0..3) |i| {
+                    std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
+                }
+                return 3 * 4;
+            },
+            .Vector2u32 => |vec| {
+                inline for (0..2) |i| {
+                    std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
+                }
+                return 2 * 4;
+            },
+            .Vector,
+            .Matrix,
+            .Array,
+            .Structure,
+            => |values| {
+                var offset: usize = 0;
+                for (values) |v| {
+                    offset += try v.read(output[offset..]);
+                }
+                return offset;
+            },
+            else => return RuntimeError.InvalidValueType,
+        }
+        return 0;
+    }
+
+    pub fn writeConst(self: *Value, input: []const u8) RuntimeError!usize {
+        return self.write(@constCast(input));
+    }
+
+    pub fn write(self: *Value, input: []u8) RuntimeError!usize {
+        switch (self.*) {
+            .Bool => |*b| {
+                b.* = if (input[0] != 0) true else false;
+                return 1;
+            },
+            .Int => |*i| {
+                switch (i.bit_count) {
+                    8 => i.value.uint8 = @bitCast(input[0]),
+                    16 => std.mem.copyForwards(u8, std.mem.asBytes(&i.value.uint16), input[0..2]),
+                    32 => std.mem.copyForwards(u8, std.mem.asBytes(&i.value.uint32), input[0..4]),
+                    64 => std.mem.copyForwards(u8, std.mem.asBytes(&i.value.uint64), input[0..8]),
+                    else => return RuntimeError.InvalidValueType,
+                }
+                return @divExact(i.bit_count, 8);
+            },
+            .Float => |*f| {
+                switch (f.bit_count) {
+                    16 => std.mem.copyForwards(u8, std.mem.asBytes(&f.value.float16), input[0..2]),
+                    32 => std.mem.copyForwards(u8, std.mem.asBytes(&f.value.float32), input[0..4]),
+                    64 => std.mem.copyForwards(u8, std.mem.asBytes(&f.value.float64), input[0..8]),
+                    else => return RuntimeError.InvalidValueType,
+                }
+                return @divExact(f.bit_count, 8);
+            },
+            .Vector4f32 => |*vec| {
+                inline for (0..4) |i| {
+                    const start = i * 4;
+                    const end = (i + 1) * 4;
+                    std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
+                }
+                return 4 * 4;
+            },
+            .Vector3f32 => |*vec| {
+                inline for (0..3) |i| {
+                    const start = i * 4;
+                    const end = (i + 1) * 4;
+                    std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
+                }
+                return 3 * 4;
+            },
+            .Vector2f32 => |*vec| {
+                inline for (0..2) |i| {
+                    const start = i * 4;
+                    const end = (i + 1) * 4;
+                    std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
+                }
+                return 2 * 4;
+            },
+            .Vector4i32 => |*vec| {
+                inline for (0..4) |i| {
+                    const start = i * 4;
+                    const end = (i + 1) * 4;
+                    std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
+                }
+                return 4 * 4;
+            },
+            .Vector3i32 => |*vec| {
+                inline for (0..3) |i| {
+                    const start = i * 4;
+                    const end = (i + 1) * 4;
+                    std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
+                }
+                return 3 * 4;
+            },
+            .Vector2i32 => |*vec| {
+                inline for (0..2) |i| {
+                    const start = i * 4;
+                    const end = (i + 1) * 4;
+                    std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
+                }
+                return 2 * 4;
+            },
+            .Vector4u32 => |*vec| {
+                inline for (0..4) |i| {
+                    const start = i * 4;
+                    const end = (i + 1) * 4;
+                    std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
+                }
+                return 4 * 4;
+            },
+            .Vector3u32 => |*vec| {
+                inline for (0..3) |i| {
+                    const start = i * 4;
+                    const end = (i + 1) * 4;
+                    std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
+                }
+                return 3 * 4;
+            },
+            .Vector2u32 => |*vec| {
+                inline for (0..2) |i| {
+                    const start = i * 4;
+                    const end = (i + 1) * 4;
+                    std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
+                }
+                return 2 * 4;
+            },
+            .Vector,
+            .Matrix,
+            .Array,
+            .Structure,
+            => |*values| {
+                var offset: usize = 0;
+                for (values.*) |*v| {
+                    offset += try v.write(input[offset..]);
+                }
+                return offset;
+            },
+            .RuntimeArray => |*arr| arr.data = input[0..],
+            else => return RuntimeError.InvalidValueType,
+        }
+        return 0;
+    }
+
+    pub fn flushPtr(self: *Value, allocator: std.mem.Allocator) RuntimeError!void {
+        switch (self.*) {
+            .Pointer => |*p| {
+                if (p.runtime_array_window) |window| {
+                    switch (p.ptr) {
+                        .common => |ptr| {
+                            _ = try ptr.read(window);
+                            ptr.deinit(allocator);
+                            allocator.destroy(ptr);
+                        },
+                        else => {},
+                    }
+                }
+                p.runtime_array_window = null;
+            },
+            else => {},
+        }
+    }
+
     fn deinit(self: *Value, allocator: std.mem.Allocator) void {
         switch (self.*) {
             .Vector, .Matrix, .Array, .Structure => |values| {
                 for (values) |*value| value.deinit(allocator);
                 allocator.free(values);
             },
-            .RuntimeArray => |opt_values| if (opt_values) |values| {
-                for (values) |*value| value.deinit(allocator);
-                allocator.free(values);
-            },
             else => {},
         }
     }
@@ -412,6 +639,7 @@ pub fn deinit(self: *Self, allocator: std.mem.Allocator) void {
             },
             .Constant => |*c| c.value.deinit(allocator),
             .Variable => |*v| v.value.deinit(allocator),
+            .AccessChain => |*a| a.value.deinit(allocator),
             .Function => |f| allocator.free(f.params),
             else => {},
         }
@@ -649,16 +877,11 @@ pub fn initValue(allocator: std.mem.Allocator, member_count: usize, results: []c
                 }
                 break :blk value;
             },
-            .RuntimeArray => |a| blk: {
-                if (member_count == 0) {
-                    break :blk Value{ .RuntimeArray = null };
-                }
-                const value: Value = .{ .RuntimeArray = allocator.alloc(Value, member_count) catch return RuntimeError.OutOfMemory };
-                errdefer allocator.free(value.RuntimeArray.?);
-                for (value.RuntimeArray.?) |*val| {
-                    val.* = try Value.init(allocator, results, a.components_type_word);
-                }
-                break :blk value;
+            .RuntimeArray => |a| .{
+                .RuntimeArray = .{
+                    .type_word = a.components_type_word,
+                    .data = &.{},
+                },
             },
             .Structure => |s| blk: {
                 const value: Value = .{ .Structure = allocator.alloc(Value, member_count) catch return RuntimeError.OutOfMemory };
@@ -676,3 +899,14 @@ pub fn initValue(allocator: std.mem.Allocator, member_count: usize, results: []c
         else => RuntimeError.InvalidSpirV,
     };
 }
+
+pub fn flushPtr(self: *Self, allocator: std.mem.Allocator) RuntimeError!void {
+    if (self.variant) |*variant| {
+        switch (variant.*) {
+            .Constant => |*c| try c.value.flushPtr(allocator),
+            .Variable => |*v| try v.value.flushPtr(allocator),
+            .AccessChain => |*a| try a.value.flushPtr(allocator),
+            else => {},
+        }
+    }
+}
diff --git a/src/Runtime.zig b/src/Runtime.zig
index 7ff3100..65ce8ee 100644
--- a/src/Runtime.zig
+++ b/src/Runtime.zig
@@ -151,43 +151,9 @@ pub fn callEntryPoint(self: *Self, allocator: std.mem.Allocator, entry_point_ind
     //}) catch return RuntimeError.OutOfMemory;
 }
 
-pub fn readDescriptorSet(self: *const Self, output: []u8, set: SpvWord, binding: SpvWord) RuntimeError!void {
+pub fn writeDescriptorSet(self: *const Self, input: []u8, set: SpvWord, binding: SpvWord) RuntimeError!void {
     if (set < lib.SPIRV_MAX_SET and binding < lib.SPIRV_MAX_SET_BINDINGS) {
-        _ = try self.readValue(output, &self.results[self.mod.bindings[set][binding]].variant.?.Variable.value);
-    } else {
-        return RuntimeError.NotFound;
-    }
-}
-
-pub fn writeDescriptorSet(self: *const Self, allocator: std.mem.Allocator, input: []const u8, set: SpvWord, binding: SpvWord) RuntimeError!void {
-    if (set < lib.SPIRV_MAX_SET and binding < lib.SPIRV_MAX_SET_BINDINGS) {
-        const variable = &self.results[self.mod.bindings[set][binding]].variant.?.Variable;
-
-        const helper = struct {
-            fn init(allocator2: std.mem.Allocator, len: usize, value: *Result.Value, type_word: SpvWord, results: []Result) RuntimeError!void {
-                const resolved = results[type_word].resolveType(results);
-
-                switch (value.*) {
-                    .RuntimeArray => |a| if (a == null) {
-                        const elem_size = resolved.variant.?.Type.getSize(results);
-                        value.* = try Result.initValue(allocator2, std.math.divCeil(usize, len, elem_size) catch unreachable, results, resolved);
-                    },
-                    .Structure => |*s| for (s.*, 0..) |*elem, i| {
-                        try @This().init(allocator2, len, elem, resolved.variant.?.Type.Structure.members_type_word[i], results);
-                    },
-                    else => {},
-                }
-            }
-        };
-        try helper.init(allocator, input.len, &variable.value, variable.type_word, self.results);
-
-        //@import("pretty").print(allocator, variable, .{
-        //    .tab_size = 4,
-        //    .max_depth = 0,
-        //    .struct_max_len = 0,
-        //    .array_max_len = 0,
-        //}) catch return RuntimeError.OutOfMemory;
-        _ = try self.writeValue(input, &variable.value);
+        _ = try self.results[self.mod.bindings[set][binding]].variant.?.Variable.value.write(input);
     } else {
         return RuntimeError.NotFound;
     }
@@ -195,7 +161,7 @@ pub fn writeDescriptorSet(self: *const Self, allocator: std.mem.Allocator, input
 
 pub fn readOutput(self: *const Self, output: []u8, result: SpvWord) RuntimeError!void {
     if (std.mem.indexOfScalar(SpvWord, &self.mod.output_locations, result)) |_| {
-        _ = try self.readValue(output, &self.results[result].variant.?.Variable.value);
+        _ = try self.results[result].variant.?.Variable.value.read(output);
     } else {
         return RuntimeError.NotFound;
     }
@@ -203,7 +169,7 @@ pub fn readOutput(self: *const Self, output: []u8, result: SpvWord) RuntimeError
 
 pub fn writeInput(self: *const Self, input: []const u8, result: SpvWord) RuntimeError!void {
     if (std.mem.indexOfScalar(SpvWord, &self.mod.input_locations, result)) |_| {
-        _ = try self.writeValue(input, &self.results[result].variant.?.Variable.value);
+        _ = try self.results[result].variant.?.Variable.value.writeConst(input);
     } else {
         return RuntimeError.NotFound;
     }
@@ -211,235 +177,19 @@ pub fn writeInput(self: *const Self, input: []const u8, result: SpvWord) Runtime
 
 pub fn writeBuiltIn(self: *const Self, input: []const u8, builtin: spv.SpvBuiltIn) RuntimeError!void {
     if (self.mod.builtins.get(builtin)) |result| {
-        _ = try self.writeValue(input, &self.results[result].variant.?.Variable.value);
+        _ = try self.results[result].variant.?.Variable.value.writeConst(input);
     } else {
         return RuntimeError.NotFound;
     }
 }
 
+pub fn flushDescriptorSets(self: *const Self, allocator: std.mem.Allocator) RuntimeError!void {
+    for (self.results) |*result| {
+        try result.flushPtr(allocator);
+    }
+}
+
 fn reset(self: *Self) void {
     self.function_stack.clearRetainingCapacity();
     self.current_function = null;
 }
-
-fn readValue(self: *const Self, output: []u8, value: *const Result.Value) RuntimeError!usize {
-    switch (value.*) {
-        .Bool => |b| {
-            output[0] = if (b == true) 1 else 0;
-            return 1;
-        },
-        .Int => |i| {
-            switch (i.bit_count) {
-                8 => output[0] = @bitCast(i.value.uint8),
-                16 => std.mem.copyForwards(u8, output[0..], std.mem.asBytes(&i.value.uint16)),
-                32 => std.mem.copyForwards(u8, output[0..], std.mem.asBytes(&i.value.uint32)),
-                64 => std.mem.copyForwards(u8, output[0..], std.mem.asBytes(&i.value.uint64)),
-                else => return RuntimeError.InvalidValueType,
-            }
-            return @divExact(i.bit_count, 8);
-        },
-        .Float => |f| {
-            switch (f.bit_count) {
-                16 => std.mem.copyForwards(u8, output[0..], std.mem.asBytes(&f.value.float16)),
-                32 => std.mem.copyForwards(u8, output[0..], std.mem.asBytes(&f.value.float32)),
-                64 => std.mem.copyForwards(u8, output[0..], std.mem.asBytes(&f.value.float64)),
-                else => return RuntimeError.InvalidValueType,
-            }
-            return @divExact(f.bit_count, 8);
-        },
-        .Vector4f32 => |vec| {
-            inline for (0..4) |i| {
-                std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
-            }
-            return 4 * 4;
-        },
-        .Vector3f32 => |vec| {
-            inline for (0..3) |i| {
-                std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
-            }
-            return 3 * 4;
-        },
-        .Vector2f32 => |vec| {
-            inline for (0..2) |i| {
-                std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
-            }
-            return 2 * 4;
-        },
-        .Vector4i32 => |vec| {
-            inline for (0..4) |i| {
-                std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
-            }
-            return 4 * 4;
-        },
-        .Vector3i32 => |vec| {
-            inline for (0..3) |i| {
-                std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
-            }
-            return 3 * 4;
-        },
-        .Vector2i32 => |vec| {
-            inline for (0..2) |i| {
-                std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
-            }
-            return 2 * 4;
-        },
-        .Vector4u32 => |vec| {
-            inline for (0..4) |i| {
-                std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
-            }
-            return 4 * 4;
-        },
-        .Vector3u32 => |vec| {
-            inline for (0..3) |i| {
-                std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
-            }
-            return 3 * 4;
-        },
-        .Vector2u32 => |vec| {
-            inline for (0..2) |i| {
-                std.mem.copyForwards(u8, output[(i * 4)..], std.mem.asBytes(&vec[i]));
-            }
-            return 2 * 4;
-        },
-        .Vector,
-        .Matrix,
-        .Array,
-        .Structure,
-        => |values| {
-            var offset: usize = 0;
-            for (values) |v| {
-                offset += try self.readValue(output[offset..], &v);
-            }
-            return offset;
-        },
-        .RuntimeArray => |opt_values| if (opt_values) |values| {
-            var offset: usize = 0;
-            for (values) |v| {
-                offset += try self.readValue(output[offset..], &v);
-            }
-            return offset;
-        },
-        else => return RuntimeError.InvalidValueType,
-    }
-    return 0;
-}
-
-fn writeValue(self: *const Self, input: []const u8, value: *Result.Value) RuntimeError!usize {
-    switch (value.*) {
-        .Bool => |*b| {
-            b.* = if (input[0] != 0) true else false;
-            return 1;
-        },
-        .Int => |*i| {
-            switch (i.bit_count) {
-                8 => i.value.uint8 = @bitCast(input[0]),
-                16 => std.mem.copyForwards(u8, std.mem.asBytes(&i.value.uint16), input[0..2]),
-                32 => std.mem.copyForwards(u8, std.mem.asBytes(&i.value.uint32), input[0..4]),
-                64 => std.mem.copyForwards(u8, std.mem.asBytes(&i.value.uint64), input[0..8]),
-                else => return RuntimeError.InvalidValueType,
-            }
-            return @divExact(i.bit_count, 8);
-        },
-        .Float => |*f| {
-            switch (f.bit_count) {
-                16 => std.mem.copyForwards(u8, std.mem.asBytes(&f.value.float16), input[0..2]),
-                32 => std.mem.copyForwards(u8, std.mem.asBytes(&f.value.float32), input[0..4]),
-                64 => std.mem.copyForwards(u8, std.mem.asBytes(&f.value.float64), input[0..8]),
-                else => return RuntimeError.InvalidValueType,
-            }
-            return @divExact(f.bit_count, 8);
-        },
-        .Vector4f32 => |*vec| {
-            inline for (0..4) |i| {
-                const start = i * 4;
-                const end = (i + 1) * 4;
-                std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
-            }
-            return 4 * 4;
-        },
-        .Vector3f32 => |*vec| {
-            inline for (0..3) |i| {
-                const start = i * 4;
-                const end = (i + 1) * 4;
-                std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
-            }
-            return 3 * 4;
-        },
-        .Vector2f32 => |*vec| {
-            inline for (0..2) |i| {
-                const start = i * 4;
-                const end = (i + 1) * 4;
-                std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
-            }
-            return 2 * 4;
-        },
-        .Vector4i32 => |*vec| {
-            inline for (0..4) |i| {
-                const start = i * 4;
-                const end = (i + 1) * 4;
-                std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
-            }
-            return 4 * 4;
-        },
-        .Vector3i32 => |*vec| {
-            inline for (0..3) |i| {
-                const start = i * 4;
-                const end = (i + 1) * 4;
-                std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
-            }
-            return 3 * 4;
-        },
-        .Vector2i32 => |*vec| {
-            inline for (0..2) |i| {
-                const start = i * 4;
-                const end = (i + 1) * 4;
-                std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
-            }
-            return 2 * 4;
-        },
-        .Vector4u32 => |*vec| {
-            inline for (0..4) |i| {
-                const start = i * 4;
-                const end = (i + 1) * 4;
-                std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
-            }
-            return 4 * 4;
-        },
-        .Vector3u32 => |*vec| {
-            inline for (0..3) |i| {
-                const start = i * 4;
-                const end = (i + 1) * 4;
-                std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
-            }
-            return 3 * 4;
-        },
-        .Vector2u32 => |*vec| {
-            inline for (0..2) |i| {
-                const start = i * 4;
-                const end = (i + 1) * 4;
-                std.mem.copyForwards(u8, std.mem.asBytes(&vec[i]), input[start..end]);
-            }
-            return 2 * 4;
-        },
-        .Vector,
-        .Matrix,
-        .Array,
-        .Structure,
-        => |*values| {
-            var offset: usize = 0;
-            for (values.*) |*v| {
-                offset += try self.writeValue(input[offset..], v);
-            }
-            return offset;
-        },
-        .RuntimeArray => |opt_values| if (opt_values) |*values| {
-            var offset: usize = 0;
-            for (values.*) |*v| {
-                offset += try self.writeValue(input[offset..], v);
-            }
-            return offset;
-        },
-        else => return RuntimeError.InvalidValueType,
-    }
-    return 0;
-}
diff --git a/src/opcodes.zig b/src/opcodes.zig
index b16197f..25a2aab 100644
--- a/src/opcodes.zig
+++ b/src/opcodes.zig
@@ -945,14 +945,13 @@ fn copyValue(dst: *Result.Value, src: *const Result.Value) void {
         fn getDstSlice(v: *Result.Value) ?[]Result.Value {
             return switch (v.*) {
                 .Vector, .Matrix, .Array, .Structure => |s| s,
-                .RuntimeArray => |s| s,
                 else => null,
             };
         }
 
         fn writeF32(dst_f32_ptr: *f32, src_v: *const Result.Value) void {
             switch (src_v.*) {
-                .Pointer => |src_ptr| switch (src_ptr) {
+                .Pointer => |src_ptr| switch (src_ptr.ptr) {
                     .f32_ptr => |src_f32_ptr| dst_f32_ptr.* = src_f32_ptr.*,
                     .common => |src_val_ptr| switch (src_val_ptr.*) {
                         .Float => |f| dst_f32_ptr.* = f.value.float32,
@@ -967,7 +966,7 @@ fn copyValue(dst: *Result.Value, src: *const Result.Value) void {
 
         fn writeI32(dst_i32_ptr: *i32, src_v: *const Result.Value) void {
             switch (src_v.*) {
-                .Pointer => |src_ptr| switch (src_ptr) {
+                .Pointer => |src_ptr| switch (src_ptr.ptr) {
                     .i32_ptr => |src_i32_ptr| dst_i32_ptr.* = src_i32_ptr.*,
                     .common => |src_val_ptr| switch (src_val_ptr.*) {
                         .Int => |i| dst_i32_ptr.* = i.value.sint32,
@@ -982,7 +981,7 @@ fn copyValue(dst: *Result.Value, src: *const Result.Value) void {
 
         fn writeU32(dst_u32_ptr: *u32, src_v: *const Result.Value) void {
             switch (src_v.*) {
-                .Pointer => |src_ptr| switch (src_ptr) {
+                .Pointer => |src_ptr| switch (src_ptr.ptr) {
                     .u32_ptr => |src_u32_ptr| dst_u32_ptr.* = src_u32_ptr.*,
                     .common => |src_val_ptr| switch (src_val_ptr.*) {
                         .Int => |i| dst_u32_ptr.* = i.value.uint32,
@@ -997,9 +996,9 @@ fn copyValue(dst: *Result.Value, src: *const Result.Value) void {
     };
 
     if (std.meta.activeTag(dst.*) == .Pointer) {
-        switch (dst.Pointer) {
+        switch (dst.Pointer.ptr) {
             .common => |dst_val_ptr| return switch (src.*) {
-                .Pointer => |src_ptr| switch (src_ptr) {
+                .Pointer => |src_ptr| switch (src_ptr.ptr) {
                     .common => |src_val_ptr| copyValue(dst_val_ptr, src_val_ptr),
                     else => dst_val_ptr.* = src.*,
                 },
@@ -1021,7 +1020,7 @@ fn copyValue(dst: *Result.Value, src: *const Result.Value) void {
     }
 
     if (std.meta.activeTag(src.*) == .Pointer) {
-        switch (src.Pointer) {
+        switch (src.Pointer.ptr) {
             .common => |src_val_ptr| {
                 copyValue(dst, src_val_ptr);
                 return;
@@ -1036,16 +1035,13 @@ fn copyValue(dst: *Result.Value, src: *const Result.Value) void {
         .Vector, .Matrix, .Array, .Structure => |src_slice| {
             helpers.copySlice(dst_slice.?, src_slice);
         },
-        .RuntimeArray => |opt_src_slice| if (opt_src_slice) |src_slice| {
-            helpers.copySlice(dst_slice.?, src_slice);
-        } else unreachable,
         else => dst.* = src.*,
     }
 }
 
 pub fn getValuePrimitiveField(comptime T: ValueType, comptime BitCount: SpvWord, v: *Result.Value) RuntimeError!*getValuePrimitiveFieldType(T, BitCount) {
     if (std.meta.activeTag(v.*) == .Pointer) {
-        return switch (v.Pointer) {
+        return switch (v.Pointer.ptr) {
             .common => |value| getValuePrimitiveField(T, BitCount, value),
             .f32_ptr => |ptr| @ptrCast(@alignCast(ptr)),
             .u32_ptr => |ptr| @ptrCast(@alignCast(ptr)),
@@ -1078,7 +1074,7 @@ pub fn getValuePrimitiveFieldType(comptime T: ValueType, comptime BitCount: SpvW
     };
 }
 
-fn opAccessChain(_: std.mem.Allocator, word_count: SpvWord, rt: *Runtime) RuntimeError!void {
+fn opAccessChain(allocator: std.mem.Allocator, word_count: SpvWord, rt: *Runtime) RuntimeError!void {
     const var_type = try rt.it.next();
     const id = try rt.it.next();
     const base_id = try rt.it.next();
@@ -1086,12 +1082,29 @@ fn opAccessChain(_: std.mem.Allocator, word_count: SpvWord, rt: *Runtime) Runtim
     const base = &rt.results[base_id];
     var value_ptr = try base.getValue();
 
+    var arena = std.heap.ArenaAllocator.init(allocator);
+    defer arena.deinit();
+
+    const arena_allocator = arena.allocator();
+
     const index_count = word_count - 3;
+
+    if (rt.results[id].variant) |*variant| {
+        switch (variant.*) {
+            .AccessChain => |*a| try a.value.flushPtr(allocator),
+            else => {},
+        }
+    }
+
     rt.results[id].variant = .{
         .AccessChain = .{
             .target = var_type,
             .value = blk: {
-                for (0..index_count) |_| {
+                var runtime_array_window: ?[]u8 = null;
+
+                for (0..index_count) |index| {
+                    const is_last = (index == index_count - 1);
+
                     const member = &rt.results[try rt.it.next()];
                     const member_value = switch ((try member.getVariant()).*) {
                         .Constant => |c| &c.value,
@@ -1102,7 +1115,7 @@ fn opAccessChain(_: std.mem.Allocator, word_count: SpvWord, rt: *Runtime) Runtim
                     switch (member_value.*) {
                         .Int => |i| {
                             if (std.meta.activeTag(value_ptr.*) == .Pointer) {
-                                value_ptr = value_ptr.Pointer.common; // Don't know if I should check for specialized pointers
+                                value_ptr = value_ptr.Pointer.ptr.common; // Don't know if I should check for specialized pointers
                             }
 
                             switch (value_ptr.*) {
@@ -1110,45 +1123,54 @@ fn opAccessChain(_: std.mem.Allocator, word_count: SpvWord, rt: *Runtime) Runtim
                                     if (i.value.uint32 >= v.len) return RuntimeError.OutOfBounds;
                                     value_ptr = &v[i.value.uint32];
                                 },
-                                .RuntimeArray => |opt_a| if (opt_a) |a| {
-                                    if (i.value.uint32 >= a.len) return RuntimeError.OutOfBounds;
-                                    value_ptr = &a[i.value.uint32];
-                                } else return RuntimeError.InvalidSpirV,
+                                .RuntimeArray => |*arr| {
+                                    const concrete_allocator = if (is_last) allocator else arena_allocator;
+                                    const type_size = (try rt.results[arr.type_word].getVariant()).Type.getSize(rt.results);
+
+                                    value_ptr = concrete_allocator.create(Result.Value) catch return RuntimeError.OutOfMemory;
+                                    errdefer concrete_allocator.destroy(value_ptr);
+
+                                    value_ptr.* = try Result.Value.init(concrete_allocator, rt.results, arr.type_word);
+                                    _ = try value_ptr.writeConst(arr.data[(type_size * i.value.uint32)..]);
+
+                                    if (is_last)
+                                        runtime_array_window = arr.data[(type_size * i.value.uint32)..];
+                                },
                                 .Vector4f32 => |*v| {
                                     if (i.value.uint32 > 4) return RuntimeError.OutOfBounds;
-                                    break :blk .{ .Pointer = .{ .f32_ptr = &v[i.value.uint32] } };
+                                    break :blk .{ .Pointer = .{ .ptr = .{ .f32_ptr = &v[i.value.uint32] } } };
                                 },
                                 .Vector3f32 => |*v| {
                                     if (i.value.uint32 > 3) return RuntimeError.OutOfBounds;
-                                    break :blk .{ .Pointer = .{ .f32_ptr = &v[i.value.uint32] } };
+                                    break :blk .{ .Pointer = .{ .ptr = .{ .f32_ptr = &v[i.value.uint32] } } };
                                 },
                                 .Vector2f32 => |*v| {
                                     if (i.value.uint32 > 2) return RuntimeError.OutOfBounds;
-                                    break :blk .{ .Pointer = .{ .f32_ptr = &v[i.value.uint32] } };
+                                    break :blk .{ .Pointer = .{ .ptr = .{ .f32_ptr = &v[i.value.uint32] } } };
                                 },
                                 .Vector4i32 => |*v| {
                                     if (i.value.uint32 > 4) return RuntimeError.OutOfBounds;
-                                    break :blk .{ .Pointer = .{ .i32_ptr = &v[i.value.uint32] } };
+                                    break :blk .{ .Pointer = .{ .ptr = .{ .i32_ptr = &v[i.value.uint32] } } };
                                 },
                                 .Vector3i32 => |*v| {
                                     if (i.value.uint32 > 3) return RuntimeError.OutOfBounds;
-                                    break :blk .{ .Pointer = .{ .i32_ptr = &v[i.value.uint32] } };
+                                    break :blk .{ .Pointer = .{ .ptr = .{ .i32_ptr = &v[i.value.uint32] } } };
                                 },
                                 .Vector2i32 => |*v| {
                                     if (i.value.uint32 > 2) return RuntimeError.OutOfBounds;
-                                    break :blk .{ .Pointer = .{ .i32_ptr = &v[i.value.uint32] } };
+                                    break :blk .{ .Pointer = .{ .ptr = .{ .i32_ptr = &v[i.value.uint32] } } };
                                 },
                                 .Vector4u32 => |*v| {
                                     if (i.value.uint32 > 4) return RuntimeError.OutOfBounds;
-                                    break :blk .{ .Pointer = .{ .u32_ptr = &v[i.value.uint32] } };
+                                    break :blk .{ .Pointer = .{ .ptr = .{ .u32_ptr = &v[i.value.uint32] } } };
                                 },
                                 .Vector3u32 => |*v| {
                                     if (i.value.uint32 > 3) return RuntimeError.OutOfBounds;
-                                    break :blk .{ .Pointer = .{ .u32_ptr = &v[i.value.uint32] } };
+                                    break :blk .{ .Pointer = .{ .ptr = .{ .u32_ptr = &v[i.value.uint32] } } };
                                 },
                                 .Vector2u32 => |*v| {
                                     if (i.value.uint32 > 2) return RuntimeError.OutOfBounds;
-                                    break :blk .{ .Pointer = .{ .u32_ptr = &v[i.value.uint32] } };
+                                    break :blk .{ .Pointer = .{ .ptr = .{ .u32_ptr = &v[i.value.uint32] } } };
                                 },
                                 else => return RuntimeError.InvalidSpirV,
                             }
@@ -1156,7 +1178,12 @@ fn opAccessChain(_: std.mem.Allocator, word_count: SpvWord, rt: *Runtime) Runtim
                         else => return RuntimeError.InvalidSpirV,
                     }
                 }
-                break :blk .{ .Pointer = .{ .common = value_ptr } };
+                break :blk .{
+                    .Pointer = .{
+                        .ptr = .{ .common = value_ptr },
+                        .runtime_array_window = runtime_array_window,
+                    },
+                };
             },
         },
     };
@@ -1206,6 +1233,16 @@ fn opCompositeConstruct(_: std.mem.Allocator, word_count: SpvWord, rt: *Runtime)
     }
 
     switch (value.*) {
+        .RuntimeArray => |arr| {
+            const type_size = (try rt.results[arr.type_word].getVariant()).Type.getSize(rt.results);
+            var offset: usize = 0;
+
+            for (0..index_count) |_| {
+                const elem_value = (try rt.results[try rt.it.next()].getVariant()).Constant.value;
+                std.mem.copyForwards(u8, arr.data[offset..(offset + type_size)], std.mem.asBytes(&elem_value));
+                offset += type_size;
+            }
+        },
         .Vector4f32 => |*vec| inline for (0..4) |i| {
             vec[i] = (try rt.results[try rt.it.next()].getVariant()).Constant.value.Float.value.float32;
         },
@@ -1233,7 +1270,7 @@ fn opCompositeConstruct(_: std.mem.Allocator, word_count: SpvWord, rt: *Runtime)
         .Vector2u32 => |*vec| inline for (0..2) |i| {
             vec[i] = (try rt.results[try rt.it.next()].getVariant()).Constant.value.Int.value.uint32;
         },
-        else => return RuntimeError.InvalidSpirV,
+        else => return RuntimeError.InvalidValueType,
     }
 }
 
@@ -1243,6 +1280,11 @@ fn opCompositeExtract(allocator: std.mem.Allocator, word_count: SpvWord, rt: *Ru
     const composite_id = try rt.it.next();
     const index_count = word_count - 3;
 
+    var arena = std.heap.ArenaAllocator.init(allocator);
+    defer arena.deinit();
+
+    const arena_allocator = arena.allocator();
+
     rt.results[id].variant = .{
         .Constant = .{
             .type_word = res_type,
@@ -1259,6 +1301,11 @@ fn opCompositeExtract(allocator: std.mem.Allocator, word_count: SpvWord, rt: *Ru
                         continue;
                     }
                     switch (composite) {
+                        .RuntimeArray => |arr| {
+                            const type_size = (try rt.results[arr.type_word].getVariant()).Type.getSize(rt.results);
+                            composite = try Result.Value.init(arena_allocator, rt.results, arr.type_word);
+                            _ = try composite.writeConst(arr.data[(type_size * member_id)..]);
+                        },
                         .Vector4f32 => |v| break :blk .{ .Float = .{ .bit_count = 32, .value = .{ .float32 = v[member_id] } } },
                         .Vector3f32 => |v| break :blk .{ .Float = .{ .bit_count = 32, .value = .{ .float32 = v[member_id] } } },
                         .Vector2f32 => |v| break :blk .{ .Float = .{ .bit_count = 32, .value = .{ .float32 = v[member_id] } } },
@@ -1268,7 +1315,7 @@ fn opCompositeExtract(allocator: std.mem.Allocator, word_count: SpvWord, rt: *Ru
                         .Vector4u32 => |v| break :blk .{ .Int = .{ .bit_count = 32, .value = .{ .uint32 = v[member_id] } } },
                         .Vector3u32 => |v| break :blk .{ .Int = .{ .bit_count = 32, .value = .{ .uint32 = v[member_id] } } },
                         .Vector2u32 => |v| break :blk .{ .Int = .{ .bit_count = 32, .value = .{ .uint32 = v[member_id] } } },
-                        else => return RuntimeError.InvalidSpirV,
+                        else => return RuntimeError.InvalidValueType,
                     }
                 }
                 break :blk try composite.dupe(allocator);
diff --git a/test/root.zig b/test/root.zig
index 1c9f407..d437451 100644
--- a/test/root.zig
+++ b/test/root.zig
@@ -24,7 +24,7 @@ pub const case = struct {
         source: []const u32,
         inputs: []const []const u8 = &.{},
         expected_outputs: []const []const u8 = &.{},
-        descriptor_sets: []const []const []const u8 = &.{},
+        descriptor_sets: []const []const []u8 = &.{},
         expected_descriptor_sets: []const []const []const u8 = &.{},
     };
 
@@ -54,11 +54,12 @@ pub const case = struct {
 
             for (config.descriptor_sets, 0..) |descriptor_set, set_index| {
                 for (descriptor_set, 0..) |descriptor_binding, binding_index| {
-                    try rt.writeDescriptorSet(allocator, descriptor_binding, @intCast(set_index), @intCast(binding_index));
+                    try rt.writeDescriptorSet(descriptor_binding, @intCast(set_index), @intCast(binding_index));
                 }
             }
 
             try rt.callEntryPoint(allocator, try rt.getEntryPointByName("main"));
+            try rt.flushDescriptorSets(allocator);
 
             for (config.expected_outputs, 0..) |expected, n| {
                 const output = try allocator.alloc(u8, expected.len);
@@ -68,13 +69,9 @@ pub const case = struct {
                 try std.testing.expectEqualSlices(u8, expected, output);
             }
 
-            for (config.expected_descriptor_sets, 0..) |expected_descriptor_set, set_index| {
-                for (expected_descriptor_set, 0..) |expected_descriptor_binding, binding_index| {
-                    const data = try allocator.alloc(u8, expected_descriptor_binding.len);
-                    defer allocator.free(data);
-
-                    try rt.readDescriptorSet(data, @intCast(set_index), @intCast(binding_index));
-                    try std.testing.expectEqualSlices(u8, expected_descriptor_binding, data);
+            for (config.expected_descriptor_sets, config.descriptor_sets) |expected_descriptor_set, descriptor_set| {
+                for (expected_descriptor_set, descriptor_set) |expected_descriptor_binding, descriptor_binding| {
+                    try std.testing.expectEqualSlices(u8, expected_descriptor_binding, descriptor_binding);
                 }
             }
         }
diff --git a/test/ssbo.zig b/test/ssbo.zig
index 47f82b6..7f9bae7 100644
--- a/test/ssbo.zig
+++ b/test/ssbo.zig
@@ -33,6 +33,8 @@ test "Simple SSBO" {
     const code = try compileNzsl(allocator, shader);
     defer allocator.free(code);
 
+    var ssbo = [_]u32{0} ** 256;
+
     var expected = [_]u32{0} ** 256;
     for (expected[0..], 0..) |*val, i| {
         val.* = @intCast(i);
@@ -44,7 +46,7 @@ test "Simple SSBO" {
             // Set 0
             &.{
                 // Binding 0
-                std.mem.asBytes(&[_]u32{0} ** 256),
+                std.mem.asBytes(&ssbo),
             },
         },
         .expected_descriptor_sets = &.{