Dora Engine Development

Dora Engine Development

Use this skill for work inside the Dora-SSR engine repository, not for ordinary game projects. First inspect the current checkout; do not answer from memory when source, scripts, or generated outputs can be checked locally.

Start From The Real Owner

Trace behavior to the source that owns it before editing:

• Engine/runtime core: Source/.
• Lua/YueScript development services: Assets/Script/Dev/, especially WebServer.yue and cli.lua.
• TypeScript runtime libraries: Assets/Script/Lib/.
• DoraX TSX runtime: Assets/Script/Lib/DoraX.ts, generated DoraX.lua, and declarations under Assets/Script/Lib/Dora/{en,zh-Hans}/.
• Web IDE frontend: Tools/dora-dora/src/.
• Docs: Docs/docs/ and matching Docs/i18n/zh-Hans/ files.
• Generated API/binding sources: inspect the generator or IDL first, then regenerate or sync generated surfaces.

For generated or vendored surfaces, patch the source of truth rather than only the generated output. Examples: Dora.h IDL for binding surfaces, Git.d.tl for generated Git docs, WebServer.yue before generated Lua, and vendored compiler/runtime sources before copied artifacts.

Change Boundaries

• Keep fixes scoped to the subsystem that decides the behavior.
• Prefer the smallest root-cause fix over UI-only patches or throttling symptoms.
• Do not edit unrelated unstaged work. If committing only staged files, validate only git diff --cached.
• When the user says a file or generated output should not be touched, treat that as a hard scope boundary.
• For Lua/TSTL special cases, check whether the repo intentionally uses manual Lua multi-return exports before changing generated binding code.
• Keep English and Chinese declaration/doc surfaces synchronized when changing public APIs.
• When two public API names do exactly the same thing, keep one name and remove the alias across source, declarations, docs, and tests.

Engine APIs And Bindings

Use the repo's binding pipeline instead of hand-editing surfaces independently:

• Wasm/Rust/Wa/C# binding surfaces should come from the relevant Dora.h IDL/generator path.
• Lua/TSTL may intentionally use manual exports, especially for Lua multi-return contracts.
• If a generated surface disagrees with a manual Lua/TSTL surface, inspect the intended contract before changing either side.
• For file I/O or resource APIs, prefer engine-consistent abstractions already used nearby, such as SDL RWops or Content, over ad hoc host APIs.
• For asset paths that may come from ZIP/APK packages, account for chunked reads; do not assume one read covers the full detection window.

When documenting module rules, inspect the current resolver and diagnostics. Dora/TSTL runtime imports reject ./ and ../; use Lua-style module names rooted from the project's init/search-path setup.

Binding Generation Commands

Run generators from the directory that owns the generator; several scripts use relative input/output paths.

For Wasm/Rust/Wa bindings, edit Tools/WasmGen/Dora.h, then run:

cd Tools/WasmGen
./gen.yue

This generator writes Wasm C++ headers under Source/Wasm/Dora/, Rust bindings under Tools/dora-rust/dora/src/, Wa bindings under Tools/dora-wa/vendor/dora/, and copies Wa vendor bindings to Assets/dora-wa/vendor when LuaFileSystem is available.

For Lua bindings, edit Tools/tolua++/Dora.h or the .pkg files, then run:

cd Tools/tolua++
./build.sh

On Windows, run the batch variant from a Visual Studio Developer Command Prompt:

cd Tools\tolua++
build.bat

The tolua generator writes Source/Lua/LuaBinding.cpp, Source/Lua/LuaCode.cpp, and Source/Lua/TealCompiler.cpp. Keep manual Lua/TSTL exports such as Source/Lua/LuaManual.cpp separate unless the task explicitly requires changing them.

For C# binding updates, use the C# generator path separately:

cd Tools/dora-cs/CSharpGen
./gen.yue

DoraX Runtime Work

DoraX has two distinct paths:

• toNode() is one-shot static scene construction.
• createRoot(parent), Root.render(), Root.update(), Root.unmount(), and signal(value) are the dynamic diff/rendering path.

Do not replace static behavior when adding dynamic behavior. For dynamic DoraX changes, check:

• Assets/Script/Lib/DoraX.ts
• Assets/Script/Lib/DoraX.lua when the TS build regenerates it
• Assets/Script/Lib/Dora/en/DoraX.d.ts
• Assets/Script/Lib/Dora/zh-Hans/DoraX.d.ts
• Assets/Script/Lib/Dora/en/jsx.d.ts
• Assets/Script/Lib/Dora/zh-Hans/jsx.d.ts
• TSX tutorials and docs if public behavior changes

When validating DoraX semantics, keep authored tests/demos in TSX. Generated Lua is only the runnable artifact.

Dora Agent And Web IDE Work

For Agent TypeScript changes, default validation is narrow:

dora ts build -f ~/Workspace/Dora-SSR/Assets/Script/Lib/Agent

Do not run a repo-wide Dora TS build for Agent work unless the user asks; it adds unrelated noise.

If /ts/build or Dora CLI returns JSON parse errors, first check whether the live WebServer is unhealthy:

• Inspect raw HTTP responses from 127.0.0.1:8866.
• Check whether /assets or /stop also returns empty 502.
• Read ~/Library/Application Support/IppClub/DoraSSR/log.txt.
• If the engine server is unreachable or localhost requests look wrong, rerun the failing CLI command with proxy environment variables cleared before treating it as a source failure:

env -u http_proxy -u https_proxy -u HTTP_PROXY -u HTTPS_PROXY -u ALL_PROXY -u all_proxy -u NO_PROXY -u no_proxy \
  dora ts build -f ~/Workspace/Dora-SSR/Assets/Script/Lib/Agent

Web IDE service reload/disconnect bugs often belong in engine/dev-service boundaries, not in the frontend. For example, Script.Dev.WebServer must not be unloaded by normal project module cache clearing.

Treat persistent host service modules, especially Script.Dev.WebServer, as outside normal game hot-reload cleanup. If a build disconnects the Web IDE, fix the module-cache boundary first; do not leave throttles, reconnect queues, or frontend timing patches as the primary solution once the boundary is understood.

Web IDE Frontend Work

Treat Web IDE features as workflow integrations, not isolated React components.

• New editor/file modes usually need updates across App.tsx, service typing such as Service.ts/EditingInfo, creation/opening UI, file-tree identity, preview/session refresh, run gating, icons, and i18n.
• Keep project run and single-file run semantics separate. Special editors should not silently turn Run This into project execution.
• Backend routes remain the authority for shared file contracts. For example, unknown text fallback must still reject folders in the /read path, even if the UI already hides or blocks folder editing.
• For editor keyboard shortcuts, prefer shell-level handling that leaves text inputs and selects to native behavior.

For dependency changes under Tools/dora-dora, package.json and pnpm-lock.yaml are the authority. Run the normal static checks, then smoke-test affected runtime surfaces. A successful build can still hide dependency compatibility breaks such as old editor APIs or asset-format expectations; pin exact versions when the code depends on that behavior.

For vendored TSTL/compiler work, compare against the upstream implementation when possible and fix the emit pipeline, dependency resolution, or save boundary directly. Do not patch only the visible symptom, such as a missing builtin helper, when the real issue is that a generated bundle file was never emitted.

When saving TypeScript sources that emit Lua, keep source-save success independent from derived Lua generation. Save the authored TS/TSX first; write generated Lua only after transpilation succeeds, and surface Lua-generation errors separately.

CLI And Dev-Service Work

status, doctor, and doctor --fix have different jobs:

• status: terse, read-only, script-friendly snapshot.
• doctor: richer diagnostics for CLI/project/service/tooling state.
• doctor --fix: the mutating local recovery path.

Keep status small. Put detailed environment output in doctor. For local browser opening or Web IDE recovery, prefer engine-side openURL through the service instead of CLI-side platform guessing.

When adding CLI features, first inspect existing routes and dispatch:

• Assets/Script/Dev/cli.lua
• Assets/Script/Dev/WebServer.yue
• generated Lua only if the workflow expects it

Prefer folding checks into existing command flows, such as build, when that matches the current CLI shape. Avoid redundant top-level wrappers for filesystem or Git operations that local command-line tools already handle well.

For --asset and other lightweight CLI-only needs, avoid initializing full engine singletons just to expose one value. Support both --asset path and --asset=path, before or after cli, and use a minimal Lua-side table when that is enough for CLI script behavior.

Native Runtime Debugging

For input, lifecycle, HTTP, and other native/runtime behavior, trace the real event or ownership path before patching symptoms:

• For input mapping, inspect the full backend path from platform event to engine/UI consumer. Do not assume button names or UI labels match the actual SDL/ImGui/controller mapping.
• Gate development-only behavior with the repo's existing platform/debug macros, such as DORA_DEBUG and desktop platform checks, instead of leaving test helpers enabled everywhere.
• For shutdown or interrupt crashes, reproduce the lifecycle path and inspect ownership/ordering at the lower layer. Do not hide a future/cancel or Life::destroy ordering bug with high-level retry or suppression code.
• For HTTP/streaming wrappers, distinguish transport reachability from protocol framing. A wrapper reporting network OK with HTTP status 0 is a protocol/status-settlement failure, not success.
• Use small focused harnesses when available or cheap to create. Standalone protocol/lifecycle tests are acceptable when a full platform build is unnecessary, but they must actually be run.

Local Engine Validation

Separate local development from CI or release work. For engine work, prefer the native run/build scripts below as the local runtime path. Use Dora CLI health checks only when the task depends on the running Web IDE/dev-service state; keep detailed CLI command usage in dora-cli-game-development.

For macOS local engine runs, the native app serves the Web IDE on HTTP 8866 and WS 8868 through Assets/Script/Dev/WebServer.yue. dora stop stops the current Dora-run project, not the engine process.

When dev-service state is suspect, restore service health first, then rerun the narrow build or test command.

Native Build Script Selection

Prefer the repo's wrapper scripts over entering third-party subdirectories manually.

• Fast local desktop loop: use Tools/build-scripts/run_macos.sh, Tools\build-scripts\run_windows.bat, or Tools/build-scripts/run_linux.sh. These check tools, build missing native dependencies, rebuild the Rust runtime and app, stop the old Dora process, and launch the Debug runtime with the repo Assets.
• Platform app build without launching: use Tools/build-scripts/build_macos.sh, build_windows.bat, build_linux.sh, build_android.sh, or build_ios.sh with debug or release.
• Native dependency rebuilds: use Tools/build-scripts/build_lib_<platform>.*. These are for missing/stale dependencies, CI/release preparation, or explicit dependency work.
• Do not manually build bgfx, SDL2, Wa, or Rust runtime from their nested directories unless the wrapper script is the thing being debugged.

When validating a local engine change, choose the script for the platform actually affected. Do not run expensive cross-platform builds unless the change touches shared build logic or release packaging.

Testing Strategy

Choose the smallest meaningful validation:

• Source formatting/scope: git diff --check or git diff --cached --check.
• Web IDE frontend changes: pnpm lint and pnpm build under Tools/dora-dora when applicable.
• Docs changes: pnpm exec docusaurus build under Docs when applicable.
• Agent TS changes: Agent-only Dora build command above.
• DoraX runtime semantics: in-engine TSX tests with marker-file assertions.
• Native engine changes: the platform-specific Debug build/run path for the touched platform.
• Web IDE dependency/compiler changes: pnpm install --frozen-lockfile, pnpm lint, pnpm build, plus a smoke test of the affected editor/runtime surface.
• Protocol or lifecycle internals: a focused harness or reproduction path that exercises the failing state, followed by the narrow platform build only when the touched code needs it.

For in-engine TSX regression tests, prefer a runner that compiles TSX, runs the generated Lua in Dora, and waits for a writable-path marker such as running, passed, or a failure message saved with Content.save(...). Marker files are more reliable than log tailing alone.

Do not downgrade TSX validation to Lua-only because the service is inconvenient to recover. Recover Dora/Web IDE health, keep the authored source in TSX, and treat generated Lua as the execution artifact.

Docs And Public Surfaces

• Keep docs aligned with generated sources and real command help.
• For CLI docs, capture current Dora cli --help output before editing command references.
• Avoid explaining internal SDL/runtime mechanics in user docs unless the user asks for internals.
• If adding a public API, sync declarations, tutorials, and both languages where the repo already maintains both.

Before Finishing

Check:

• The actual source owner was inspected.
• Generated files were updated only when they are part of the expected workflow.
• English and Chinese public surfaces are in sync when relevant.
• Local service failures were not mistaken for source failures.
• Validation command scope matches the subsystem changed.
• Unrelated worktree changes were left alone.
• The fix did not add duplicate API names, redundant CLI wrappers, or local UI workarounds before the real control point was checked.
• UI/frontend changes were integrated through the full workflow surface, not just the visible component.
• Dependency, compiler, networking, and lifecycle changes were verified against the runtime behavior that actually failed.