SDK Architecture

Migo is an embeddable Canvas/WebGL mini-game runtime container. migo.* is the sole capability surface the engine installs for content; adapters such as migo-wx-adapter and migo-web-adapter live in separate repositories and are not built-in engine modules. Migo has no DOM or CSS and must not be described as a general-purpose WebView replacement.

Component Topology

flowchart TB
  Bundle[Mini-game bundle] --> Adapter[Standalone adapter (optional)]
  Adapter --> Boundary[migo.* capability boundary]
  Boundary --> Core[Rust core]
  Core --> V8[V8 JavaScript runtime]
  Core --> Render[Skia / Canvas / WebGL]
  Host[Host App] <--> SDK[C ABI (language facade above Android)]
  SDK <--> Core
  Host --> Services[surface · input · storage · network · ads]

Plain-text equivalent

1. The mini-game bundle accesses runtime capabilities exclusively through the migo.* capability boundary; optional standalone adapters live outside the engine.
2. The Rust core orchestrates the V8 JavaScript runtime and the Skia rendering back-end, producing Canvas/WebGL content.
3. The host app creates and manages sessions through the C ABI — the one interface shared by all four platforms; the Java facade (MigoRuntime/MigoGameView) conventionally used on Android is only a language wrapper above this ABI layer. Services such as surface, input, storage, network, and ads are provided by the host.
4. Migo provides no DOM, CSS, page layout, or browser document object model.

Session Lifecycle

Diagrams show function names only; full signatures are in the Session and Surface reference pages.

Initialization

sequenceDiagram
  participant Host as Host App
  participant ABI as Migo C ABI
  participant Engine as Engine
  participant Session as Session
  participant Content as Bundle
  Host->>ABI: migo_engine_create
  ABI->>Engine: create engine
  Host->>ABI: migo_session_create
  ABI->>Session: create session
  Host->>ABI: migo_session_set_host_callbacks
  Host->>ABI: migo_session_attach_surface
  Host->>ABI: migo_session_load_content
  ABI->>Content: load bundle

Plain-text equivalent

1. The host calls migo_engine_create first, then migo_session_create to obtain a session handle.
2. After the session is created, install migo_session_set_host_callbacks, then supply a render target with migo_session_attach_surface.
3. migo_session_load_content loads the content bundle exactly once; a second call returns MIGO_ERROR_INVALID_STATE.

Per-frame and Input

sequenceDiagram
  participant Host as Host App
  participant ABI as Migo C ABI
  participant Session as Session
  participant Content as Bundle
  loop Every frame
    Host->>ABI: migo_session_notify_vsync
    ABI->>Session: advance frame and render
    Session-->>Host: host callbacks / frame output
  end
  Host->>ABI: migo_session_send_touch
  ABI->>Content: forward input

Plain-text equivalent

1. The host calls migo_session_notify_vsync at the display system’s cadence to advance frames; only after receiving on_request_frame.
2. Touch events enter the content input stream via migo_session_send_touch; other input types use the corresponding migo_session_send_* interfaces in input.h.

Teardown

sequenceDiagram
  participant Host as Host App
  participant ABI as Migo C ABI
  participant Engine as Engine
  participant Session as Session
  Host->>ABI: migo_surface_begin_detach
  Host->>ABI: migo_surface_release_query
  ABI-->>Host: query release state
  Host->>ABI: migo_session_destroy
  ABI->>Session: destroy session
  Host->>ABI: migo_engine_destroy
  ABI->>Engine: destroy engine

Plain-text equivalent

1. When a surface is lost, call migo_surface_begin_detach first, then poll with migo_surface_release_query until the release state is complete.
2. Once released, destroy the session and engine in ownership order; the handle is invalid immediately after destroy returns MIGO_OK.

Platform Boundaries

• Android, Linux, Windows: use V8; the host integrates through the Android facade or the linkable C ABI runtime.
• HarmonyOS NEXT: due to anonymous-memory execution restrictions introduced in HarmonyOS 5.0.0 (12), Migo runs V8 in jitless mode; do not claim JIT-level performance on NEXT.
• Apple: external-frame sessions use CAMetalLayer; the implementation has not completed production-readiness verification, so production performance claims must not be made.

Migo’s build process and platform dependencies are documented in the repository’s BUILD.md.