diff --git a/source/app.cpp b/source/app.cpp
index fc82c67..da5c475 100644
--- a/source/app.cpp
+++ b/source/app.cpp
@@ -12,270 +12,213 @@ import coral.math;
 
 import oar;
 
-namespace app {
-	struct directory : public coral::fs {
-		struct rules {
-			bool can_read;
+using native_path = coral::fixed_buffer<4096>;
 
-			bool can_write;
-		};
-
-		virtual rules access_rules() const = 0;
-
-		virtual coral::slice<char const> native_path() const = 0;
+struct native_file : public coral::file_reader, public coral::file_writer {
+	enum class open_mode {
+		read_only,
+		overwrite,
 	};
 
-	struct file : public coral::file_reader, public coral::file_writer {
-		enum class open_mode {
-			read_only,
-			overwrite,
-		};
-
-		enum class [[nodiscard]] close_result {
-			ok,
-			io_unavailable,
-		};
-
-		enum class [[nodiscard]] open_result {
-			ok,
-			io_unavailable,
-			access_denied,
-			not_found,
-		};
-
-		file(directory * file_directory) : rw_ops{nullptr} {
-			this->file_directory = file_directory;
-		}
-
-		close_result close() {
-			if (::SDL_RWclose(this->rw_ops) != 0) return close_result::io_unavailable;
-
-			this->rw_ops = nullptr;
-
-			return close_result::ok;
-		}
-
-		bool is_open() const {
-			return this->rw_ops != nullptr;
-		}
-
-		open_result open(coral::path const & file_path, open_mode mode) {
-			if (this->is_open()) switch (this->close()) {
-				case close_result::ok: break;
-				case close_result::io_unavailable: return open_result::io_unavailable;
-				default: coral::unreachable();
-			}
-
-			// Windows system path max is something like 512 bytes (depending on the version) and
-			// on Linux it's 4096.
-			coral::fixed_buffer<4096> path_buffer{0};
-
-			if (!path_buffer.write(this->file_directory->native_path().as_bytes()).is_ok())
-				// What kind of directory path is being used that would be longer than 4096 bytes?
-				return open_result::not_found;
-
-			if (!path_buffer.write(file_path.as_slice().as_bytes()).is_ok())
-				// This happening is still implausible but slightly more reasonable?
-				return open_result::not_found;
-
-			// No room for zero terminator.
-			if (path_buffer.is_full()) return open_result::not_found;
-
-			switch (mode) {
-				case open_mode::read_only: {
-					if (!this->file_directory->access_rules().can_read)
-						return open_result::access_denied;
-
-					this->rw_ops = ::SDL_RWFromFile(
-						reinterpret_cast<char const *>(path_buffer.begin()), "rb");
-
-					break;
-				}
-
-				case open_mode::overwrite: {
-					if (!this->file_directory->access_rules().can_write)
-						return open_result::access_denied;
-
-					this->rw_ops = ::SDL_RWFromFile(
-						reinterpret_cast<char const *>(path_buffer.begin()), "wb");
-
-					break;
-				}
-
-				default: coral::unreachable();
-			}
-
-			if (this->rw_ops == nullptr) return open_result::not_found;
-
-			return open_result::ok;
-		}
-
-		coral::expected<coral::usize, coral::io_error> read(coral::slice<coral::u8> const & data) override {
-			if (!this->is_open()) return coral::io_error::unavailable;
-
-			coral::usize const data_read{::SDL_RWread(this->rw_ops, data.pointer, sizeof(uint8_t), data.length)};
-
-			if ((data_read == 0) && (::SDL_GetError() != nullptr)) return coral::io_error::unavailable;
-
-			return data_read;
-		}
-
-		coral::expected<coral::u64, coral::io_error> seek(coral::u64 offset) override {
-			if (!this->is_open()) return coral::io_error::unavailable;
-
-			// TODO: Fix cast.
-			coral::i64 const byte_position{
-				::SDL_RWseek(this->rw_ops, static_cast<coral::i64>(offset), RW_SEEK_SET)};
-
-			if (byte_position == -1) return coral::io_error::unavailable;
-
-			return static_cast<coral::u64>(byte_position);
-		}
-
-		coral::expected<coral::u64, coral::io_error> tell() override {
-			if (!this->is_open()) return coral::io_error::unavailable;
-
-			coral::i64 const byte_position{::SDL_RWseek(this->rw_ops, 0, RW_SEEK_SET)};
-
-			if (byte_position == -1) return coral::io_error::unavailable;
-
-			return static_cast<coral::u64>(byte_position);
-		}
-
-		coral::expected<coral::usize, coral::io_error> write(coral::slice<coral::u8 const> const & data) override {
-			if (!this->is_open()) return coral::io_error::unavailable;
-
-			coral::usize const data_written{::SDL_RWwrite(this->rw_ops, data.pointer, sizeof(uint8_t), data.length)};
-
-			if ((data_written == 0) && (::SDL_GetError() != nullptr)) return coral::io_error::unavailable;
-
-			return data_written;
-		}
-
-		private:
-		directory * file_directory;
-
-		::SDL_RWops * rw_ops;
+	enum class [[nodiscard]] close_result {
+		ok,
+		io_unavailable,
 	};
-}
 
-struct base_directory : public app::directory {
-	base_directory() : directory_path{} {
-		char * const path{::SDL_GetBasePath()};
+	enum class [[nodiscard]] open_result {
+		ok,
+		io_unavailable,
+		access_denied,
+		not_found,
+	};
 
-		if (path == nullptr) return;
+	native_file() = default;
 
-		coral::usize path_length{0};
+	close_result close() {
+		if (SDL_RWclose(this->rw_ops) != 0) return close_result::io_unavailable;
 
-		while (path[path_length] != 0) path_length += 1;
+		this->rw_ops = nullptr;
 
-		if (path_length == 0) {
-			::SDL_free(path);
+		return close_result::ok;
+	}
 
-			return;
+	bool is_open() const {
+		return this->rw_ops != nullptr;
+	}
+
+	open_result open(native_path const & file_path, open_mode mode) {
+		if (this->is_open()) switch (this->close()) {
+			case close_result::ok: break;
+			case close_result::io_unavailable: return open_result::io_unavailable;
+			default: coral::unreachable();
 		}
 
-		this->directory_path = {path, path_length};
+		// No room for zero terminator.
+		if (file_path.is_full()) return open_result::not_found;
+
+		switch (mode) {
+			case open_mode::read_only: {
+				this->rw_ops = SDL_RWFromFile(file_path.as_slice().as_chars().begin(), "rb");
+
+				break;
+			}
+
+			case open_mode::overwrite: {
+				this->rw_ops = SDL_RWFromFile(file_path.as_slice().as_chars().begin(), "wb");
+
+				break;
+			}
+
+			default: coral::unreachable();
+		}
+
+		if (this->rw_ops == nullptr) return open_result::not_found;
+
+		return open_result::ok;
 	}
 
-	~base_directory() override {
-		::SDL_free(this->directory_path.begin());
+	coral::expected<coral::usize, coral::io_error> read(coral::slice<coral::u8> const & data) override {
+		if (!this->is_open()) return coral::io_error::unavailable;
+
+		coral::usize const data_read{SDL_RWread(this->rw_ops, data.pointer, sizeof(uint8_t), data.length)};
+
+		if ((data_read == 0) && (SDL_GetError() != nullptr)) return coral::io_error::unavailable;
+
+		return data_read;
 	}
 
-	rules access_rules() const override {
-		return {
-			.can_read = true,
-			.can_write = false,
-		};
+	coral::expected<coral::u64, coral::io_error> seek(coral::u64 offset) override {
+		if (!this->is_open()) return coral::io_error::unavailable;
+
+		// TODO: Fix cast.
+		coral::i64 const byte_position{
+			SDL_RWseek(this->rw_ops, static_cast<coral::i64>(offset), RW_SEEK_SET)};
+
+		if (byte_position == -1) return coral::io_error::unavailable;
+
+		return static_cast<coral::u64>(byte_position);
 	}
 
-	coral::slice<const char> native_path() const override {
-		return this->directory_path;
+	coral::expected<coral::u64, coral::io_error> tell() override {
+		if (!this->is_open()) return coral::io_error::unavailable;
+
+		coral::i64 const byte_position{SDL_RWseek(this->rw_ops, 0, RW_SEEK_SET)};
+
+		if (byte_position == -1) return coral::io_error::unavailable;
+
+		return static_cast<coral::u64>(byte_position);
 	}
 
-	void read_file(coral::path const & file_path, coral::callable<void(coral::file_reader &)> const & then) override {
-		if (this->directory_path.length == 0) return;
+	coral::expected<coral::usize, coral::io_error> write(coral::slice<coral::u8 const> const & data) override {
+		if (!this->is_open()) return coral::io_error::unavailable;
 
-		app::file file{this};
+		coral::usize const data_written{SDL_RWwrite(this->rw_ops, data.pointer, sizeof(uint8_t), data.length)};
 
-		if (file.open(file_path, app::file::open_mode::read_only) != app::file::open_result::ok)
-			return;
+		if ((data_written == 0) && (SDL_GetError() != nullptr)) return coral::io_error::unavailable;
 
-		then(file);
-
-		if (file.close() != app::file::close_result::ok) return;
+		return data_written;
 	}
 
-	void write_file(coral::path const & file_path, coral::callable<void(coral::file_writer &)> const & then) override {
-		// Directory is read-only.
-	}
-
-	protected:
-	coral::slice<char> directory_path;
+	private:
+	SDL_RWops * rw_ops{nullptr};
 };
 
-struct user_directory : public app::directory {
-	user_directory(coral::path const & title) : directory_path{} {
-		char * const path{::SDL_GetPrefPath("ona", title.begin())};
+struct sandboxed_fs : public coral::fs {
+	sandboxed_fs() {
+		char * const path{SDL_GetBasePath()};
 
 		if (path == nullptr) return;
 
-		coral::usize path_length{0};
+		for (coral::usize index = 0; path[index] != 0; index += 1)
+			this->sandbox_path.put(path[index]);
 
-		while (path[path_length] != 0) path_length += 1;
+		SDL_free(path);
 
-		if (path_length == 0) {
-			::SDL_free(path);
-
-			return;
-		}
-
-		this->directory_path = {path, path_length};
+		this->access_rules.can_read = true;
 	}
 
-	~user_directory() override {
-		::SDL_free(this->directory_path.begin());
+	sandboxed_fs(coral::path const & organization_name, coral::path const & app_name) {
+		char * const path{SDL_GetPrefPath(organization_name.begin(), app_name.begin())};
+
+		if (path == nullptr) return;
+
+		for (coral::usize index = 0; path[index] != 0; index += 1)
+			this->sandbox_path.put(path[index]);
+
+		SDL_free(path);
+
+		this->access_rules.can_read = true;
 	}
 
-	rules access_rules() const override {
-		return {
-			.can_read = true,
-			.can_write = false,
-		};
-	}
-
-	coral::slice<const char> native_path() const override {
-		return this->directory_path;
+	access_rules query_access() override {
+		return this->access_rules;
 	}
 
 	void read_file(coral::path const & file_path, coral::callable<void(coral::file_reader &)> const & then) override {
-		if (this->directory_path.length == 0) return;
+		if (!this->access_rules.can_read) return;
 
-		app::file file{this};
+		native_path sandbox_file_path{0};
+		{
+			coral::expected const written = sandbox_file_path.write(this->sandbox_path.as_slice());
 
-		if (file.open(file_path, app::file::open_mode::read_only) != app::file::open_result::ok)
-			return;
+			if (!written.is_ok() || (written.value() != this->sandbox_path.count())) return;
+		}
+
+		{
+			coral::expected const written =
+				sandbox_file_path.write(file_path.as_slice().as_bytes());
+
+			if (!written.is_ok() || (written.value() != this->sandbox_path.count())) return;
+		}
+
+		native_file file;
+
+		if (file.open(sandbox_file_path, native_file::open_mode::read_only) !=
+			native_file::open_result::ok) return;
 
 		then(file);
 
-		if (file.close() != app::file::close_result::ok) return;
+		if (file.close() != native_file::close_result::ok)
+			// Error orphaned file handle!
+			return;
 	}
 
 	void write_file(coral::path const & file_path, coral::callable<void(coral::file_writer &)> const & then) override {
-		if (this->directory_path.length == 0) return;
+		if (!this->access_rules.can_write) return;
 
-		app::file file{this};
+		native_path sandbox_file_path{0};
+		{
+			coral::expected const written = sandbox_file_path.write(this->sandbox_path.as_slice());
 
-		if (file.open(file_path, app::file::open_mode::overwrite) != app::file::open_result::ok)
-			return;
+			if (!written.is_ok() || (written.value() != this->sandbox_path.count())) return;
+		}
+
+		{
+			coral::expected const written =
+				sandbox_file_path.write(file_path.as_slice().as_bytes());
+
+			if (!written.is_ok() || (written.value() != this->sandbox_path.count())) return;
+		}
+
+		native_file file;
+
+		if (file.open(sandbox_file_path, native_file::open_mode::overwrite) !=
+			native_file::open_result::ok) return;
 
 		then(file);
 
-		if (file.close() != app::file::close_result::ok) return;
+		if (file.close() != native_file::close_result::ok)
+			// Error orphaned file handle!
+			return;
 	}
 
-	protected:
-	coral::slice<char> directory_path;
+	private:
+	native_path sandbox_path{0};
+
+	access_rules access_rules{
+		.can_read = false,
+		.can_write = false,
+	};
 };
 
 export namespace app {
@@ -285,17 +228,27 @@ export namespace app {
 		error,
 	};
 
-	struct system {
-		system(coral::path const & title) : user_directory{title},
-			res_archive{&base_directory, res_archive_path} {}
+	struct client {
+		coral::fs & base() {
+			return this->base_sandbox;
+		}
 
-		app::directory & base_dir() {
-			return this->base_directory;
+		void display(coral::u16 screen_width, coral::u16 screen_height) {
+			SDL_SetWindowSize(this->window, screen_width, screen_height);
+			SDL_ShowWindow(this->window);
+		}
+
+		void log(log_level level, coral::slice<char const> const & message) {
+			coral::i32 const length{static_cast<coral::i32>(
+				coral::min(message.length, static_cast<size_t>(coral::i32_max)))};
+
+			SDL_LogMessage(SDL_LOG_CATEGORY_APPLICATION,
+				SDL_LOG_PRIORITY_INFO, "%.*s", length, message.pointer);
 		}
 
 		bool poll() {
-			while (::SDL_PollEvent(&this->sdl_event) != 0) {
-				switch (this->sdl_event.type) {
+			while (SDL_PollEvent(&this->event) != 0) {
+				switch (this->event.type) {
 					case SDL_QUIT: return false;
 				}
 			}
@@ -303,124 +256,62 @@ export namespace app {
 			return true;
 		}
 
-		coral::fs & res_fs() {
-			return this->res_archive;
+		coral::fs & resources() {
+			return this->resources_archive;
 		}
 
-		void log(app::log_level level, coral::slice<char const> const & message) {
-			coral::i32 const length{static_cast<coral::i32>(
-				coral::min(message.length, static_cast<size_t>(coral::i32_max)))};
+		static int run(coral::path const & title, coral::callable<int(client &)> const & start) {
+			constexpr int windowpos {SDL_WINDOWPOS_UNDEFINED};
+			constexpr coral::u32 windowflags {SDL_WINDOW_HIDDEN};
+			constexpr int window_width {640};
+			constexpr int window_height {480};
 
-			::SDL_LogMessage(SDL_LOG_CATEGORY_APPLICATION,
-				SDL_LOG_PRIORITY_INFO, "%.*s", length, message.pointer);
+			SDL_Window * const window {SDL_CreateWindow(
+				title.begin(), windowpos, windowpos, window_width, window_height, windowflags)};
+
+			if (window == nullptr) return 0xff;
+
+			struct : public coral::allocator {
+				coral::u8 * reallocate(coral::u8 * allocation, coral::usize requested_size) override {
+					return reinterpret_cast<coral::u8 *>(SDL_realloc(allocation, requested_size));
+				}
+
+				void deallocate(void * allocation) override {
+					SDL_free(allocation);
+				}
+			} allocator;
+
+			client app_client {&allocator, window, title};
+
+			return start(app_client);
 		}
 
 		coral::allocator & thread_safe_allocator() {
-			return this->allocator;
+			return *this->allocator;
 		}
 
-		app::directory & user_dir() {
-			return this->user_directory;
+		coral::fs & user() {
+			return this->user_sandbox;
 		}
 
 		private:
-		static constexpr coral::path res_archive_path{"base.oar"};
+		client(coral::allocator * allocator, SDL_Window * window,
+			coral::path const & title) : user_sandbox{"ona", title} {
 
-		::SDL_Event sdl_event;
+			this->allocator = allocator;
+			this->window = window;
+		}
 
-		struct : public coral::allocator {
-			coral::u8 * reallocate(coral::u8 * maybe_allocation, coral::usize requested_size) override {
-				return reinterpret_cast<coral::u8 *>(::SDL_malloc(requested_size));
-			}
+		coral::allocator * allocator;
 
-			void deallocate(void * allocation) override {
-				::SDL_free(allocation);
-			}
-		} allocator;
+		SDL_Window * window;
 
-		struct base_directory base_directory;
+		SDL_Event event;
 
-		struct user_directory user_directory;
+		sandboxed_fs base_sandbox;
 
-		oar::archive res_archive;
+		sandboxed_fs user_sandbox;
+
+		oar::archive resources_archive{&base_sandbox, "base.oar"};
 	};
-
-	struct graphics {
-		enum class [[nodiscard]] show_result {
-			ok,
-			out_of_memory,
-		};
-
-		struct canvas {
-			coral::color background_color;
-		};
-
-		graphics(coral::path const & title) {
-			this->retitle(title);
-		}
-
-		void present() {
-			if (this->sdl_renderer != nullptr) {
-				::SDL_RenderPresent(this->sdl_renderer);
-			}
-		}
-
-		void render(canvas & source_canvas) {
-			if (this->sdl_renderer != nullptr) {
-				SDL_SetRenderDrawColor(this->sdl_renderer, source_canvas.background_color.to_r8(),
-					source_canvas.background_color.to_g8(), source_canvas.background_color.to_b8(),
-						source_canvas.background_color.to_a8());
-
-				SDL_RenderClear(this->sdl_renderer);
-			}
-		}
-
-		void retitle(coral::path const & title) {
-			this->title = title;
-
-			if (this->sdl_window != nullptr)
-				::SDL_SetWindowTitle(this->sdl_window, this->title.begin());
-		}
-
-		show_result show(coral::u16 physical_width, coral::u16 physical_height) {
-			if (this->sdl_window == nullptr) {
-				constexpr int sdl_windowpos = SDL_WINDOWPOS_UNDEFINED;
-				constexpr coral::u32 sdl_windowflags = 0;
-
-				this->sdl_window = ::SDL_CreateWindow(this->title.begin(), sdl_windowpos,
-					sdl_windowpos, static_cast<int>(physical_width), static_cast<int>(physical_height),
-						sdl_windowflags);
-
-				if (this->sdl_window == nullptr) return show_result::out_of_memory;
-			} else {
-				::SDL_ShowWindow(this->sdl_window);
-			}
-
-			if (this->sdl_renderer == nullptr) {
-				constexpr coral::u32 sdl_rendererflags = 0;
-
-				this->sdl_renderer = ::SDL_CreateRenderer(this->sdl_window, -1, sdl_rendererflags);
-
-				if (this->sdl_renderer == nullptr) return show_result::out_of_memory;
-			}
-
-			return show_result::ok;
-		}
-
-		private:
-		coral::path title;
-
-		::SDL_Window * sdl_window = nullptr;
-
-		::SDL_Renderer * sdl_renderer = nullptr;
-	};
-
-	using graphical_runnable = coral::callable<int(system &, graphics &)>;
-
-	int display(coral::path const & title, graphical_runnable const & run) {
-		system app_system{title};
-		graphics app_graphics{title};
-
-		return run(app_system, app_graphics);
-	}
 }
diff --git a/source/oar.cpp b/source/oar.cpp
index 332fbb3..9dc338d 100644
--- a/source/oar.cpp
+++ b/source/oar.cpp
@@ -171,6 +171,13 @@ export namespace oar {
 			this->archive_path = archive_path;
 		}
 
+		access_rules query_access() override {
+			return {
+				.can_read = true,
+				.can_write = false,
+			};
+		}
+
 		void read_file(coral::path const & file_path,
 			coral::callable<void(coral::file_reader &)> const & then) override {
 
diff --git a/source/runtime.cpp b/source/runtime.cpp
index 3a7a422..b7b98aa 100644
--- a/source/runtime.cpp
+++ b/source/runtime.cpp
@@ -9,12 +9,12 @@ import coral.math;
 import coral.sequence;
 
 extern "C" int main(int argc, char const * const * argv) {
-	return app::display("Ona Runtime", [](app::system & system, app::graphics & graphics) -> int {
+	return app::client::run("Ona Runtime", [](app::client & client) -> int {
 		constexpr coral::path config_path{"config.kym"};
 		bool is_config_loaded{false};
 
-		system.res_fs().read_file(config_path, [&](coral::reader & file) {
-			coral::allocator * const allocator{&system.thread_safe_allocator()};
+		client.resources().read_file(config_path, [&](coral::reader & file) {
+			coral::allocator * const allocator{&client.thread_safe_allocator()};
 
 			coral::stack<coral::u8> script_source{allocator};
 			{
@@ -24,13 +24,13 @@ extern "C" int main(int argc, char const * const * argv) {
 				if (!coral::stream(script_writer, file, stream_buffer).is_ok()) return;
 			}
 
-			system.log(app::log_level::notice, script_source.as_slice().as_chars());
+			client.log(app::log_level::notice, script_source.as_slice().as_chars());
 
 			is_config_loaded = true;
 		});
 
 		if (!is_config_loaded) {
-			coral::stack<coral::u8> error_message{&system.thread_safe_allocator()};
+			coral::stack<coral::u8> error_message{&client.thread_safe_allocator()};
 			{
 				coral::contiguous_writer error_writer{&error_message};
 
@@ -44,11 +44,10 @@ extern "C" int main(int argc, char const * const * argv) {
 			return coral::u8_max;
 		}
 
-		// app::canvas canvas_2d();
+		client.display(1280, 800);
+
+		while (client.poll()) {
 
-		while (system.poll()) {
-			// canvas_2d.render(graphics);
-			graphics.present();
 		}
 
 		return 0;