From 2dcc8a96d3d0e8a9be139882c5ec4653ab03e8f9 Mon Sep 17 00:00:00 2001
From: Kayshen-X <kayshen_xu@163.com>
Date: Tue, 5 May 2026 12:23:10 +0800
Subject: [PATCH] feat(workspace): pin Jian submodule and shell wrapper deps
 (Step 1a Task 1)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Anchor v19 pivot at the workspace level: vendor Jian as a git submodule
pinned to fork commit ad13ce6 (P0.5 mini-gate GO; skia-safe 0.78 → 0.97 +
new pub draw_on_canvas adapter), wire jian-core / jian-skia / jian-host-desktop
as path deps with explicit version per spec §12.2, and re-export the
Jian render/geometry/scene types from shell-core so shell-native can
translate the OP RenderBackend facade into jian DrawOp commands.

shell-core stays wasm32-clean: only jian-core (already wasm32-validated
in P0.5) plus glam / bitflags / thiserror / tracing land here.
shell-native picks up the full P0-pinned GL stack (skia-safe 0.97.0,
glutin 0.32.3, glutin-winit 0.5.0, glow 0.17.0, winit 0.30.13,
raw-window-handle 0.6.2, scopeguard 1.2) plus jian-skia (textlayout)
and target-gated jian-host-desktop (default-features = false, no `run`
feature so we skip Jian's softbuffer raster present path — OP owns its
own GPU swap_buffers per spec §3.6).

Adds OP RenderBackend trait + Rect / Color (with RED/GREEN/BLUE/BLACK/
WHITE/TRANSPARENT named constants per spec §5.2) + TextLayout facade
that wraps jian_core::render::TextRun explicitly (TextRun has no Default
impl, fields enumerated to honour spec §5.2 round-2 CONCERN-1 fix).

Boundary checks all pass:
- wasm32 shell-web metadata: no jian-host-desktop / jian-skia
- aarch64-linux-android shell-native metadata: no jian-host-desktop
- shell-core src: no glutin / skia_safe / winit / glow imports

Tasks 2-4 (SharedSkiaContext + NativeBackend + ShellEvent mapping +
acceptance) follow per plan v7.
---
 .gitmodules                                   |   3 +
 Cargo.lock                                    | 970 +++++++++++++-----
 Cargo.toml                                    |   1 +
 crates/openpencil-shell-core/Cargo.toml       |  17 +-
 crates/openpencil-shell-core/src/jian.rs      |  41 +
 crates/openpencil-shell-core/src/lib.rs       |  26 +-
 .../src/render_backend.rs                     | 181 ++++
 .../tests/jian_re_export.rs                   |  87 ++
 crates/openpencil-shell-native/Cargo.toml     |  44 +-
 crates/openpencil-shell-native/src/lib.rs     |  27 +-
 crates/openpencil-shell-web/src/lib.rs        |  20 +-
 vendor/jian                                   |   1 +
 12 files changed, 1117 insertions(+), 301 deletions(-)
 create mode 100644 crates/openpencil-shell-core/src/jian.rs
 create mode 100644 crates/openpencil-shell-core/src/render_backend.rs
 create mode 100644 crates/openpencil-shell-core/tests/jian_re_export.rs
 create mode 160000 vendor/jian

diff --git a/.gitmodules b/.gitmodules
index 08e063365..e7d955d35 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -4,3 +4,6 @@
 [submodule "vendor/agent"]
 	path = vendor/agent
 	url = https://github.com/ZSeven-W/agent-rs.git
+[submodule "vendor/jian"]
+	path = vendor/jian
+	url = git@github.com:Kayshen-X/jian.git
diff --git a/Cargo.lock b/Cargo.lock
index b063528da..138bafcd8 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -18,6 +18,12 @@ version = "0.1.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "366ffbaa4442f4684d91e2cd7c5ea7c4ed8add41959a31447066e279e432b618"
 
+[[package]]
+name = "adler2"
+version = "2.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "320119579fcad9c21884f5c4861d16174d0e06250625266f50fe6898340abefa"
+
 [[package]]
 name = "ahash"
 version = "0.8.12"
@@ -32,10 +38,13 @@ dependencies = [
 ]
 
 [[package]]
-name = "allocator-api2"
-version = "0.2.21"
+name = "aho-corasick"
+version = "1.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "683d7910e743518b0e34f1186f92494becacb047c7b6bf616c96772180fef923"
+checksum = "ddd31a130427c27518df266943a5308ed92d4b226cc639f5a8f1002816174301"
+dependencies = [
+ "memchr",
+]
 
 [[package]]
 name = "android-activity"
@@ -80,6 +89,17 @@ version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "175571dd1d178ced59193a6fc02dde1b972eb0bc56c892cde9beeceac5bf0f6b"
 
+[[package]]
+name = "async-trait"
+version = "0.1.89"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9035ad2d096bed7955a320ee7e2230574d28fd3c3a0f186cbea1ff3c7eed5dbb"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "atomic-waker"
 version = "1.1.2"
@@ -92,6 +112,32 @@ version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c08606f8c3cbf4ce6ec8e28fb0014a2c086708fe954eaa885384a6165172e7e8"
 
+[[package]]
+name = "base64"
+version = "0.22.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "72b3254f16251a8381aa12e40e3c4d2f0199f8c6508fbecb9d91f575e0fbb8c6"
+
+[[package]]
+name = "bindgen"
+version = "0.72.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "993776b509cfb49c750f11b8f07a46fa23e0a1386ffc01fb1e7d343efc387895"
+dependencies = [
+ "bitflags 2.11.1",
+ "cexpr",
+ "clang-sys",
+ "itertools",
+ "log",
+ "prettyplease",
+ "proc-macro2",
+ "quote",
+ "regex",
+ "rustc-hash",
+ "shlex",
+ "syn",
+]
+
 [[package]]
 name = "bitflags"
 version = "1.3.2"
@@ -110,7 +156,7 @@ version = "0.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2c132eebf10f5cad5289222520a4a058514204aed6d791f1cf4fe8088b82d15f"
 dependencies = [
- "objc2",
+ "objc2 0.5.2",
 ]
 
 [[package]]
@@ -124,20 +170,12 @@ name = "bytemuck"
 version = "1.25.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c8efb64bd706a16a1bdde310ae86b351e4d21550d98d056f22f8a7f7a2183fec"
-dependencies = [
- "bytemuck_derive",
-]
 
 [[package]]
-name = "bytemuck_derive"
-version = "1.10.2"
+name = "byteorder"
+version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f9abbd1bc6865053c427f7198e6af43bfdedc55ab791faed4fbd361d789575ff"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn",
-]
+checksum = "1fd0f2584146f6f2ef48085050886acf353beff7305ebd1ae69500e27c67f64b"
 
 [[package]]
 name = "bytes"
@@ -183,6 +221,15 @@ dependencies = [
  "shlex",
 ]
 
+[[package]]
+name = "cexpr"
+version = "0.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6fac387a98bb7c37292057cffc56d62ecb629900026402633ae9160df93a8766"
+dependencies = [
+ "nom",
+]
+
 [[package]]
 name = "cfg-if"
 version = "1.0.4"
@@ -195,6 +242,26 @@ version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "613afe47fcd5fac7ccf1db93babcb082c5994d996f20b8b159f2ad1658eb5724"
 
+[[package]]
+name = "cgl"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0ced0551234e87afee12411d535648dd89d2e7f34c78b753395567aff3d447ff"
+dependencies = [
+ "libc",
+]
+
+[[package]]
+name = "clang-sys"
+version = "1.8.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0b023947811758c97c59bf9d1c188fd619ad4718dcaa767947df1cadb14f39f4"
+dependencies = [
+ "glob",
+ "libc",
+ "libloading",
+]
+
 [[package]]
 name = "combine"
 version = "4.6.7"
@@ -255,15 +322,12 @@ dependencies = [
 ]
 
 [[package]]
-name = "core-text"
-version = "20.1.0"
+name = "crc32fast"
+version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c9d2790b5c08465d49f8dc05c8bcae9fea467855947db39b0f8145c091aaced5"
+checksum = "9481c1c90cbf2ac953f07c8d4a58aa3945c425b7185c9154d67a65e4230da511"
 dependencies = [
- "core-foundation",
- "core-graphics",
- "foreign-types",
- "libc",
+ "cfg-if",
 ]
 
 [[package]]
@@ -278,6 +342,12 @@ version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f27ae1dd37df86211c42e150270f82743308803d90a6f6e6651cd730d5e1732f"
 
+[[package]]
+name = "deunicode"
+version = "1.6.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "abd57806937c9cc163efc8ea3910e00a62e2aeb0b8119f1793a978088f8f6b04"
+
 [[package]]
 name = "dispatch"
 version = "0.2.0"
@@ -285,14 +355,13 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bd0c93bb4b0c6d9b77f4435b0ae98c24d17f1c45b2ff844c6151a07256ca923b"
 
 [[package]]
-name = "displaydoc"
-version = "0.2.5"
+name = "dispatch2"
+version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "97369cbbc041bc366949bc74d34658d6cda5621039731c6310521892a3a20ae0"
+checksum = "1e0e367e4e7da84520dedcac1901e4da967309406d1e51017ae1abfb97adbd38"
 dependencies = [
- "proc-macro2",
- "quote",
- "syn",
+ "bitflags 2.11.1",
+ "objc2 0.6.4",
 ]
 
 [[package]]
@@ -316,6 +385,18 @@ version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d8b14ccef22fc6f5a8f4d7d768562a182c04ce9a3b3157b91390b52ddfdf1a76"
 
+[[package]]
+name = "dyn-clone"
+version = "1.0.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d0881ea181b1df73ff77ffaaf9c7544ecc11e82fba9b5f27b262a3c73a332555"
+
+[[package]]
+name = "either"
+version = "1.15.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "48c757948c5ede0e46177b7add2e67155f70e33c07fea8284df6576da70b3719"
+
 [[package]]
 name = "equivalent"
 version = "1.0.2"
@@ -341,6 +422,17 @@ dependencies = [
  "num-traits",
 ]
 
+[[package]]
+name = "filetime"
+version = "0.2.27"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f98844151eee8917efc50bd9e8318cb963ae8b297431495d3f758616ea5c57db"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "libredox",
+]
+
 [[package]]
 name = "find-msvc-tools"
 version = "0.1.9"
@@ -348,44 +440,13 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5baebc0774151f905a1a2cc41989300b1e6fbb29aff0ceffa1064fdd3088d582"
 
 [[package]]
-name = "font-types"
-version = "0.7.3"
+name = "flate2"
+version = "1.1.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b3971f9a5ca983419cdc386941ba3b9e1feba01a0ab888adf78739feb2798492"
+checksum = "843fba2746e448b37e26a819579957415c8cef339bf08564fe8b7ddbd959573c"
 dependencies = [
- "bytemuck",
-]
-
-[[package]]
-name = "fontconfig-cache-parser"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a7f8afb20c8069fd676d27b214559a337cc619a605d25a87baa90b49a06f3b18"
-dependencies = [
- "bytemuck",
- "thiserror 1.0.69",
-]
-
-[[package]]
-name = "fontique"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3b008f3607a8e8935b2607eef514164b8223020614c8ad684434a0cd668d280c"
-dependencies = [
- "core-foundation",
- "core-text",
- "fontconfig-cache-parser",
- "hashbrown 0.14.5",
- "icu_locid",
- "memmap2",
- "objc2",
- "objc2-foundation",
- "peniko",
- "roxmltree",
- "skrifa",
- "smallvec",
- "windows",
- "windows-core",
+ "crc32fast",
+ "miniz_oxide",
 ]
 
 [[package]]
@@ -415,12 +476,71 @@ version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "aa9a19cbb55df58761df49b23516a86d432839add4af60fc256da840f66ed35b"
 
+[[package]]
+name = "futures"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b147ee9d1f6d097cef9ce628cd2ee62288d963e16fb287bd9286455b241382d"
+dependencies = [
+ "futures-channel",
+ "futures-core",
+ "futures-executor",
+ "futures-io",
+ "futures-sink",
+ "futures-task",
+ "futures-util",
+]
+
+[[package]]
+name = "futures-channel"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "07bbe89c50d7a535e539b8c17bc0b49bdb77747034daa8087407d655f3f7cc1d"
+dependencies = [
+ "futures-core",
+ "futures-sink",
+]
+
 [[package]]
 name = "futures-core"
 version = "0.3.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7e3450815272ef58cec6d564423f6e755e25379b217b0bc688e295ba24df6b1d"
 
+[[package]]
+name = "futures-executor"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "baf29c38818342a3b26b5b923639e7b1f4a61fc5e76102d4b1981c6dc7a7579d"
+dependencies = [
+ "futures-core",
+ "futures-task",
+ "futures-util",
+]
+
+[[package]]
+name = "futures-io"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cecba35d7ad927e23624b22ad55235f2239cfa44fd10428eecbeba6d6a717718"
+
+[[package]]
+name = "futures-macro"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e835b70203e41293343137df5c0664546da5745f82ec9b84d40be8336958447b"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "futures-sink"
+version = "0.3.32"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c39754e157331b013978ec91992bde1ac089843443c49cbc7f46150b0fad0893"
+
 [[package]]
 name = "futures-task"
 version = "0.3.32"
@@ -433,8 +553,13 @@ version = "0.3.32"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "389ca41296e6190b48053de0321d02a77f32f8a5d2461dd38762c0593805c6d6"
 dependencies = [
+ "futures-channel",
  "futures-core",
+ "futures-io",
+ "futures-macro",
+ "futures-sink",
  "futures-task",
+ "memchr",
  "pin-project-lite",
  "slab",
 ]
@@ -462,20 +587,126 @@ dependencies = [
 ]
 
 [[package]]
-name = "grid"
-version = "0.15.0"
+name = "gl_generator"
+version = "0.14.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "36119f3a540b086b4e436bb2b588cf98a68863470e0e880f4d0842f112a3183a"
+checksum = "1a95dfc23a2b4a9a2f5ab41d194f8bfda3cabec42af4e39f08c339eb2a0c124d"
+dependencies = [
+ "khronos_api",
+ "log",
+ "xml-rs",
+]
+
+[[package]]
+name = "glam"
+version = "0.29.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8babf46d4c1c9d92deac9f7be466f76dfc4482b6452fc5024b5e8daf6ffeb3ee"
+
+[[package]]
+name = "glob"
+version = "0.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0cc23270f6e1808e30a928bdc84dea0b9b4136a8bc82338574f23baf47bbd280"
+
+[[package]]
+name = "glow"
+version = "0.17.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "29038e1c483364cc6bb3cf78feee1816002e127c331a1eec55a4d202b9e1adb5"
+dependencies = [
+ "js-sys",
+ "slotmap",
+ "wasm-bindgen",
+ "web-sys",
+]
+
+[[package]]
+name = "glutin"
+version = "0.32.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "12124de845cacfebedff80e877bb37b5b75c34c5a4c89e47e1cdd67fb6041325"
+dependencies = [
+ "bitflags 2.11.1",
+ "cfg_aliases",
+ "cgl",
+ "dispatch2",
+ "glutin_egl_sys",
+ "glutin_glx_sys",
+ "glutin_wgl_sys",
+ "libloading",
+ "objc2 0.6.4",
+ "objc2-app-kit 0.3.2",
+ "objc2-core-foundation",
+ "objc2-foundation 0.3.2",
+ "once_cell",
+ "raw-window-handle",
+ "wayland-sys",
+ "windows-sys 0.52.0",
+ "x11-dl",
+]
+
+[[package]]
+name = "glutin-winit"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "85edca7075f8fc728f28cb8fbb111a96c3b89e930574369e3e9c27eb75d3788f"
+dependencies = [
+ "cfg_aliases",
+ "glutin",
+ "raw-window-handle",
+ "winit",
+]
+
+[[package]]
+name = "glutin_egl_sys"
+version = "0.7.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4c4680ba6195f424febdc3ba46e7a42a0e58743f2edb115297b86d7f8ecc02d2"
+dependencies = [
+ "gl_generator",
+ "windows-sys 0.52.0",
+]
+
+[[package]]
+name = "glutin_glx_sys"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8a7bb2938045a88b612499fbcba375a77198e01306f52272e692f8c1f3751185"
+dependencies = [
+ "gl_generator",
+ "x11-dl",
+]
+
+[[package]]
+name = "glutin_wgl_sys"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2c4ee00b289aba7a9e5306d57c2d05499b2e5dc427f84ac708bd2c090212cf3e"
+dependencies = [
+ "gl_generator",
+]
+
+[[package]]
+name = "grid"
+version = "0.14.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "be136d9dacc2a13cc70bb6c8f902b414fb2641f8db1314637c6b7933411a8f82"
+
+[[package]]
+name = "hash32"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "47d60b12902ba28e2730cd37e95b8c9223af2808df9e902d4df49588d1470606"
+dependencies = [
+ "byteorder",
+]
 
 [[package]]
 name = "hashbrown"
-version = "0.14.5"
+version = "0.12.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e5274423e17b7c9fc20b6e7e208532f9b19825d82dfd615708b70edd83df41f1"
-dependencies = [
- "ahash",
- "allocator-api2",
-]
+checksum = "8a9ee70c43aaf417c914396645a0fa852624801b24ebb7ae78fe8272889ac888"
 
 [[package]]
 name = "hashbrown"
@@ -483,6 +714,22 @@ version = "0.17.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "4f467dd6dccf739c208452f8014c75c18bb8301b050ad1cfb27153803edb0f51"
 
+[[package]]
+name = "heapless"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0bfb9eb618601c89945a70e254898da93b13be0388091d42117462b265bb3fad"
+dependencies = [
+ "hash32",
+ "stable_deref_trait",
+]
+
+[[package]]
+name = "heck"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2304e00983f87ffb38b55b444b5e3b60a884b5d30c0fca7d82fe33449bbe55ea"
+
 [[package]]
 name = "hermit-abi"
 version = "0.5.2"
@@ -490,15 +737,14 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "fc0fef456e4baa96da950455cd02c081ca953b141298e41db3fc7e36b1da849c"
 
 [[package]]
-name = "icu_locid"
-version = "1.5.0"
+name = "indexmap"
+version = "1.9.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "13acbb8371917fc971be86fc8057c41a64b521c184808a698c02acc242dbf637"
+checksum = "bd070e393353796e801d209ad339e89596eb4c8d430d18ede6a1cced8fafbd99"
 dependencies = [
- "displaydoc",
- "litemap",
- "tinystr",
- "writeable",
+ "autocfg",
+ "hashbrown 0.12.3",
+ "serde",
 ]
 
 [[package]]
@@ -511,12 +757,79 @@ dependencies = [
  "hashbrown 0.17.0",
 ]
 
+[[package]]
+name = "itertools"
+version = "0.13.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "413ee7dfc52ee1a4949ceeb7dbc8a33f2d6c088194d9f922fb8318faf1f01186"
+dependencies = [
+ "either",
+]
+
 [[package]]
 name = "itoa"
 version = "1.0.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8f42a60cbdf9a97f5d2305f08a87dc4e09308d1276d28c869c684d7777685682"
 
+[[package]]
+name = "jian-core"
+version = "0.0.1"
+dependencies = [
+ "async-trait",
+ "bitflags 2.11.1",
+ "deunicode",
+ "euclid",
+ "futures",
+ "jian-ops-schema",
+ "rstar",
+ "serde",
+ "serde_json",
+ "slotmap",
+ "smallvec",
+ "taffy",
+ "thiserror 1.0.69",
+]
+
+[[package]]
+name = "jian-host-desktop"
+version = "0.0.1"
+dependencies = [
+ "async-trait",
+ "jian-core",
+ "jian-ops-schema",
+ "jian-skia",
+ "objc2 0.5.2",
+ "objc2-app-kit 0.2.2",
+ "objc2-foundation 0.2.2",
+ "serde",
+ "serde_json",
+ "windows-sys 0.61.2",
+ "winit",
+]
+
+[[package]]
+name = "jian-ops-schema"
+version = "0.0.1"
+dependencies = [
+ "schemars",
+ "serde",
+ "serde_json",
+ "thiserror 1.0.69",
+]
+
+[[package]]
+name = "jian-skia"
+version = "0.0.1"
+dependencies = [
+ "base64",
+ "futures",
+ "jian-core",
+ "jian-ops-schema",
+ "raw-window-handle",
+ "skia-safe",
+]
+
 [[package]]
 name = "jni"
 version = "0.22.4"
@@ -598,15 +911,10 @@ dependencies = [
 ]
 
 [[package]]
-name = "kurbo"
-version = "0.11.3"
+name = "khronos_api"
+version = "3.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c62026ae44756f8a599ba21140f350303d4f08dcdcc71b5ad9c9bb8128c13c62"
-dependencies = [
- "arrayvec",
- "euclid",
- "smallvec",
-]
+checksum = "e2db585e1d738fc771bf08a151420d3ed193d9d895a36df7f6f8a9456b911ddc"
 
 [[package]]
 name = "libc"
@@ -624,6 +932,12 @@ dependencies = [
  "windows-link",
 ]
 
+[[package]]
+name = "libm"
+version = "0.2.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b6d2cec3eae94f9f509c767b45932f1ada8350c4bdb85af2fcab4a3c14807981"
+
 [[package]]
 name = "libredox"
 version = "0.1.16"
@@ -648,12 +962,6 @@ version = "0.12.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "32a66949e030da00e8c7d4434b251670a91556f4144941d37452769c25d58a53"
 
-[[package]]
-name = "litemap"
-version = "0.7.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "23fb14cb19457329c82206317a5663005a4d404783dc74f4252769b0d5f42856"
-
 [[package]]
 name = "log"
 version = "0.4.29"
@@ -675,6 +983,22 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "minimal-lexical"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "68354c5c6bd36d73ff3feceb05efa59b6acb7626617f4962be322a825e61f79a"
+
+[[package]]
+name = "miniz_oxide"
+version = "0.8.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1fa76a2c86f704bdb222d66965fb3d63269ce38518b83cb0575fca855ebb6316"
+dependencies = [
+ "adler2",
+ "simd-adler32",
+]
+
 [[package]]
 name = "ndk"
 version = "0.9.0"
@@ -705,6 +1029,16 @@ dependencies = [
  "jni-sys 0.3.1",
 ]
 
+[[package]]
+name = "nom"
+version = "7.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d273983c5a657a70a3e8f2a01329822f3b8c8172b73826411a55751e404a0a4a"
+dependencies = [
+ "memchr",
+ "minimal-lexical",
+]
+
 [[package]]
 name = "num-traits"
 version = "0.2.19"
@@ -712,6 +1046,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "071dfc062690e90b734c0b2273ce72ad0ffa95f0c74596bc250dcfd960262841"
 dependencies = [
  "autocfg",
+ "libm",
 ]
 
 [[package]]
@@ -752,6 +1087,15 @@ dependencies = [
  "objc2-encode",
 ]
 
+[[package]]
+name = "objc2"
+version = "0.6.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3a12a8ed07aefc768292f076dc3ac8c48f3781c8f2d5851dd3d98950e8c5a89f"
+dependencies = [
+ "objc2-encode",
+]
+
 [[package]]
 name = "objc2-app-kit"
 version = "0.2.2"
@@ -761,13 +1105,25 @@ dependencies = [
  "bitflags 2.11.1",
  "block2",
  "libc",
- "objc2",
+ "objc2 0.5.2",
  "objc2-core-data",
  "objc2-core-image",
- "objc2-foundation",
+ "objc2-foundation 0.2.2",
  "objc2-quartz-core",
 ]
 
+[[package]]
+name = "objc2-app-kit"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d49e936b501e5c5bf01fda3a9452ff86dc3ea98ad5f283e1455153142d97518c"
+dependencies = [
+ "bitflags 2.11.1",
+ "objc2 0.6.4",
+ "objc2-core-foundation",
+ "objc2-foundation 0.3.2",
+]
+
 [[package]]
 name = "objc2-cloud-kit"
 version = "0.2.2"
@@ -776,9 +1132,9 @@ checksum = "74dd3b56391c7a0596a295029734d3c1c5e7e510a4cb30245f8221ccea96b009"
 dependencies = [
  "bitflags 2.11.1",
  "block2",
- "objc2",
+ "objc2 0.5.2",
  "objc2-core-location",
- "objc2-foundation",
+ "objc2-foundation 0.2.2",
 ]
 
 [[package]]
@@ -788,8 +1144,8 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a5ff520e9c33812fd374d8deecef01d4a840e7b41862d849513de77e44aa4889"
 dependencies = [
  "block2",
- "objc2",
- "objc2-foundation",
+ "objc2 0.5.2",
+ "objc2-foundation 0.2.2",
 ]
 
 [[package]]
@@ -800,8 +1156,19 @@ checksum = "617fbf49e071c178c0b24c080767db52958f716d9eabdf0890523aeae54773ef"
 dependencies = [
  "bitflags 2.11.1",
  "block2",
- "objc2",
- "objc2-foundation",
+ "objc2 0.5.2",
+ "objc2-foundation 0.2.2",
+]
+
+[[package]]
+name = "objc2-core-foundation"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2a180dd8642fa45cdb7dd721cd4c11b1cadd4929ce112ebd8b9f5803cc79d536"
+dependencies = [
+ "bitflags 2.11.1",
+ "dispatch2",
+ "objc2 0.6.4",
 ]
 
 [[package]]
@@ -811,8 +1178,8 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "55260963a527c99f1819c4f8e3b47fe04f9650694ef348ffd2227e8196d34c80"
 dependencies = [
  "block2",
- "objc2",
- "objc2-foundation",
+ "objc2 0.5.2",
+ "objc2-foundation 0.2.2",
  "objc2-metal",
 ]
 
@@ -823,9 +1190,9 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "000cfee34e683244f284252ee206a27953279d370e309649dc3ee317b37e5781"
 dependencies = [
  "block2",
- "objc2",
+ "objc2 0.5.2",
  "objc2-contacts",
- "objc2-foundation",
+ "objc2-foundation 0.2.2",
 ]
 
 [[package]]
@@ -844,7 +1211,18 @@ dependencies = [
  "block2",
  "dispatch",
  "libc",
- "objc2",
+ "objc2 0.5.2",
+]
+
+[[package]]
+name = "objc2-foundation"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e3e0adef53c21f888deb4fa59fc59f7eb17404926ee8a6f59f5df0fd7f9f3272"
+dependencies = [
+ "bitflags 2.11.1",
+ "objc2 0.6.4",
+ "objc2-core-foundation",
 ]
 
 [[package]]
@@ -854,9 +1232,9 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a1a1ae721c5e35be65f01a03b6d2ac13a54cb4fa70d8a5da293d7b0020261398"
 dependencies = [
  "block2",
- "objc2",
- "objc2-app-kit",
- "objc2-foundation",
+ "objc2 0.5.2",
+ "objc2-app-kit 0.2.2",
+ "objc2-foundation 0.2.2",
 ]
 
 [[package]]
@@ -867,8 +1245,8 @@ checksum = "dd0cba1276f6023976a406a14ffa85e1fdd19df6b0f737b063b95f6c8c7aadd6"
 dependencies = [
  "bitflags 2.11.1",
  "block2",
- "objc2",
- "objc2-foundation",
+ "objc2 0.5.2",
+ "objc2-foundation 0.2.2",
 ]
 
 [[package]]
@@ -879,8 +1257,8 @@ checksum = "e42bee7bff906b14b167da2bac5efe6b6a07e6f7c0a21a7308d40c960242dc7a"
 dependencies = [
  "bitflags 2.11.1",
  "block2",
- "objc2",
- "objc2-foundation",
+ "objc2 0.5.2",
+ "objc2-foundation 0.2.2",
  "objc2-metal",
 ]
 
@@ -890,8 +1268,8 @@ version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0a684efe3dec1b305badae1a28f6555f6ddd3bb2c2267896782858d5a78404dc"
 dependencies = [
- "objc2",
- "objc2-foundation",
+ "objc2 0.5.2",
+ "objc2-foundation 0.2.2",
 ]
 
 [[package]]
@@ -902,12 +1280,12 @@ checksum = "b8bb46798b20cd6b91cbd113524c490f1686f4c4e8f49502431415f3512e2b6f"
 dependencies = [
  "bitflags 2.11.1",
  "block2",
- "objc2",
+ "objc2 0.5.2",
  "objc2-cloud-kit",
  "objc2-core-data",
  "objc2-core-image",
  "objc2-core-location",
- "objc2-foundation",
+ "objc2-foundation 0.2.2",
  "objc2-link-presentation",
  "objc2-quartz-core",
  "objc2-symbols",
@@ -922,8 +1300,8 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "44fa5f9748dbfe1ca6c0b79ad20725a11eca7c2218bceb4b005cb1be26273bfe"
 dependencies = [
  "block2",
- "objc2",
- "objc2-foundation",
+ "objc2 0.5.2",
+ "objc2-foundation 0.2.2",
 ]
 
 [[package]]
@@ -934,9 +1312,9 @@ checksum = "76cfcbf642358e8689af64cee815d139339f3ed8ad05103ed5eaf73db8d84cb3"
 dependencies = [
  "bitflags 2.11.1",
  "block2",
- "objc2",
+ "objc2 0.5.2",
  "objc2-core-location",
- "objc2-foundation",
+ "objc2-foundation 0.2.2",
 ]
 
 [[package]]
@@ -953,16 +1331,27 @@ version = "0.1.0"
 name = "openpencil-shell-core"
 version = "0.1.0"
 dependencies = [
- "parley",
+ "bitflags 2.11.1",
+ "glam",
+ "jian-core",
  "serde",
- "taffy",
+ "thiserror 1.0.69",
+ "tracing",
 ]
 
 [[package]]
 name = "openpencil-shell-native"
 version = "0.1.0"
 dependencies = [
+ "glow",
+ "glutin",
+ "glutin-winit",
+ "jian-host-desktop",
+ "jian-skia",
  "openpencil-shell-core",
+ "raw-window-handle",
+ "scopeguard",
+ "skia-safe",
  "winit",
 ]
 
@@ -995,18 +1384,6 @@ dependencies = [
  "ttf-parser",
 ]
 
-[[package]]
-name = "parley"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3a67bad26b7aca3f1046305d0d7edba9a77b14e74a9ff9136968178c8e6c8e61"
-dependencies = [
- "fontique",
- "peniko",
- "skrifa",
- "swash",
-]
-
 [[package]]
 name = "pen-codegen"
 version = "0.1.0"
@@ -1049,16 +1426,6 @@ dependencies = [
  "thiserror 1.0.69",
 ]
 
-[[package]]
-name = "peniko"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "0a648c93f502a0bef0a9cb47fa1335994958a2744667d3f82defe513f276741a"
-dependencies = [
- "kurbo",
- "smallvec",
-]
-
 [[package]]
 name = "percent-encoding"
 version = "2.3.2"
@@ -1117,6 +1484,16 @@ dependencies = [
  "windows-sys 0.61.2",
 ]
 
+[[package]]
+name = "prettyplease"
+version = "0.2.37"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "479ca8adacdd7ce8f1fb39ce9ecccbfe93a3f1344b3d0d97f20bc0196208f62b"
+dependencies = [
+ "proc-macro2",
+ "syn",
+]
+
 [[package]]
 name = "proc-macro-crate"
 version = "3.5.0"
@@ -1165,16 +1542,6 @@ version = "0.6.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "20675572f6f24e9e76ef639bc5552774ed45f1c30e2951e1e99c59888861c539"
 
-[[package]]
-name = "read-fonts"
-version = "0.22.7"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "69aacb76b5c29acfb7f90155d39759a29496aebb49395830e928a9703d2eec2f"
-dependencies = [
- "bytemuck",
- "font-types",
-]
-
 [[package]]
 name = "redox_syscall"
 version = "0.4.1"
@@ -1194,10 +1561,50 @@ dependencies = [
 ]
 
 [[package]]
-name = "roxmltree"
-version = "0.19.0"
+name = "regex"
+version = "1.12.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3cd14fd5e3b777a7422cca79358c57a8f6e3a703d9ac187448d0daf220c2407f"
+checksum = "e10754a14b9137dd7b1e3e5b0493cc9171fdd105e0ab477f51b72e7f3ac0e276"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-automata",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-automata"
+version = "0.4.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6e1dd4122fc1595e8162618945476892eefca7b88c52820e74af6262213cae8f"
+dependencies = [
+ "aho-corasick",
+ "memchr",
+ "regex-syntax",
+]
+
+[[package]]
+name = "regex-syntax"
+version = "0.8.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dc897dd8d9e8bd1ed8cdad82b5966c3e0ecae09fb1907d58efaa013543185d0a"
+
+[[package]]
+name = "rstar"
+version = "0.12.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "421400d13ccfd26dfa5858199c30a5d76f9c54e0dba7575273025b43c5175dbb"
+dependencies = [
+ "heapless",
+ "num-traits",
+ "smallvec",
+]
+
+[[package]]
+name = "rustc-hash"
+version = "2.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "94300abf3f1ae2e2b8ffb7b58043de3d399c73fa6f4b73826402a5c457614dbe"
 
 [[package]]
 name = "rustc_version"
@@ -1249,12 +1656,43 @@ dependencies = [
  "winapi-util",
 ]
 
+[[package]]
+name = "schemars"
+version = "0.8.22"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3fbf2ae1b8bc8e02df939598064d22402220cd5bbcca1c76f7d6a310974d5615"
+dependencies = [
+ "dyn-clone",
+ "indexmap 1.9.3",
+ "schemars_derive",
+ "serde",
+ "serde_json",
+]
+
+[[package]]
+name = "schemars_derive"
+version = "0.8.22"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "32e265784ad618884abaea0600a9adf15393368d840e0222d101a072f3f7534d"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "serde_derive_internals",
+ "syn",
+]
+
 [[package]]
 name = "scoped-tls"
 version = "1.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e1cf6437eb19a8f4a6cc0f7dca544973b0b78843adbfeb3683d1a94a0024a294"
 
+[[package]]
+name = "scopeguard"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "94143f37725109f92c262ed2cf5e59bce7498c01bcc1502d7b9afe439a4e9f49"
+
 [[package]]
 name = "sctk-adwaita"
 version = "0.10.1"
@@ -1304,12 +1742,24 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "serde_derive_internals"
+version = "0.29.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "18d26a20a969b9e3fdf2fc2d9f21eda6c40e2de84c9408bb5d3b05d499aae711"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "serde_json"
 version = "1.0.149"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "83fc039473c5595ace860d8c4fafa220ff474b3fc6bfdb4293327f1a37e94d86"
 dependencies = [
+ "indexmap 2.14.0",
  "itoa",
  "memchr",
  "serde",
@@ -1317,12 +1767,27 @@ dependencies = [
  "zmij",
 ]
 
+[[package]]
+name = "serde_spanned"
+version = "1.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6662b5879511e06e8999a8a235d848113e942c9124f211511b16466ee2995f26"
+dependencies = [
+ "serde_core",
+]
+
 [[package]]
 name = "shlex"
 version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
 
+[[package]]
+name = "simd-adler32"
+version = "0.3.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "703d5c7ef118737c72f1af64ad2f6f8c5e1921f818cdcb97b8fe6fc69bf66214"
+
 [[package]]
 name = "simd_cesu8"
 version = "1.1.1"
@@ -1340,13 +1805,30 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e3a9fe34e3e7a50316060351f37187a3f546bce95496156754b601a5fa71b76e"
 
 [[package]]
-name = "skrifa"
-version = "0.22.3"
+name = "skia-bindings"
+version = "0.97.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8e1c44ad1f6c5bdd4eefed8326711b7dbda9ea45dfd36068c427d332aa382cbe"
+checksum = "d6e3bcf8f25bf047e83110838463e8d06696c12fccc3d3794adf448b4d81f34b"
 dependencies = [
- "bytemuck",
- "read-fonts",
+ "bindgen",
+ "cc",
+ "flate2",
+ "heck",
+ "pkg-config",
+ "regex",
+ "serde_json",
+ "tar",
+ "toml",
+]
+
+[[package]]
+name = "skia-safe"
+version = "0.97.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "935d4d174fb749bac9265eb41cad75039d32fda2d9c1a1e81b430df0e210a409"
+dependencies = [
+ "bitflags 2.11.1",
+ "skia-bindings",
 ]
 
 [[package]]
@@ -1404,21 +1886,18 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "stable_deref_trait"
+version = "1.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6ce2be8dc25455e1f91df71bfa12ad37d7af1092ae736f3a6cd0e37bc7810596"
+
 [[package]]
 name = "strict-num"
 version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6637bab7722d379c8b41ba849228d680cc12d0a45ba1fa2b48f2a30577a06731"
 
-[[package]]
-name = "swash"
-version = "0.1.19"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cbd59f3f359ddd2c95af4758c18270eddd9c730dde98598023cdabff472c2ca2"
-dependencies = [
- "skrifa",
-]
-
 [[package]]
 name = "syn"
 version = "2.0.117"
@@ -1432,9 +1911,9 @@ dependencies = [
 
 [[package]]
 name = "taffy"
-version = "0.6.3"
+version = "0.5.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "136661daffcdfb128afb0d45a8f7e88078739196d64d7ffa47f8513f4a00a6d7"
+checksum = "9cb893bff0f80ae17d3a57e030622a967b8dbc90e38284d9b4b1442e23873c94"
 dependencies = [
  "arrayvec",
  "grid",
@@ -1443,6 +1922,17 @@ dependencies = [
  "slotmap",
 ]
 
+[[package]]
+name = "tar"
+version = "0.4.45"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "22692a6476a21fa75fdfc11d452fda482af402c008cdbaf3476414e122040973"
+dependencies = [
+ "filetime",
+ "libc",
+ "xattr",
+]
+
 [[package]]
 name = "thiserror"
 version = "1.0.69"
@@ -1509,12 +1999,18 @@ dependencies = [
 ]
 
 [[package]]
-name = "tinystr"
-version = "0.7.6"
+name = "toml"
+version = "1.1.2+spec-1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "9117f5d4db391c1cf6927e7bea3db74b9a1c1add8f7eda9ffd5364f40f57b82f"
+checksum = "81f3d15e84cbcd896376e6730314d59fb5a87f31e4b038454184435cd57defee"
 dependencies = [
- "displaydoc",
+ "indexmap 2.14.0",
+ "serde_core",
+ "serde_spanned",
+ "toml_datetime",
+ "toml_parser",
+ "toml_writer",
+ "winnow",
 ]
 
 [[package]]
@@ -1532,7 +2028,7 @@ version = "0.25.11+spec-1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0b59c4d22ed448339746c59b905d24568fcbb3ab65a500494f7b8c3e97739f2b"
 dependencies = [
- "indexmap",
+ "indexmap 2.14.0",
  "toml_datetime",
  "toml_parser",
  "winnow",
@@ -1547,6 +2043,12 @@ dependencies = [
  "winnow",
 ]
 
+[[package]]
+name = "toml_writer"
+version = "1.1.1+spec-1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "756daf9b1013ebe47a8776667b466417e2d4c5679d441c26230efd9ef78692db"
+
 [[package]]
 name = "tracing"
 version = "0.1.44"
@@ -1554,14 +2056,29 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "63e71662fa4b2a2c3a26f570f037eb95bb1f85397f3cd8076caed2f026a6d100"
 dependencies = [
  "pin-project-lite",
+ "tracing-attributes",
  "tracing-core",
 ]
 
+[[package]]
+name = "tracing-attributes"
+version = "0.1.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7490cfa5ec963746568740651ac6781f701c9c5ea257c58e057f3ba8cf69e8da"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "tracing-core"
 version = "0.1.36"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "db97caf9d906fbde555dd62fa95ddba9eecfd14cb388e4f491a66d74cd5fb79a"
+dependencies = [
+ "once_cell",
+]
 
 [[package]]
 name = "ttf-parser"
@@ -1766,6 +2283,7 @@ checksum = "d8eab23fefc9e41f8e841df4a9c707e8a8c4ed26e944ef69297184de2785e3be"
 dependencies = [
  "dlib",
  "log",
+ "once_cell",
  "pkg-config",
 ]
 
@@ -1798,76 +2316,12 @@ dependencies = [
  "windows-sys 0.61.2",
 ]
 
-[[package]]
-name = "windows"
-version = "0.58.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dd04d41d93c4992d421894c18c8b43496aa748dd4c081bac0dc93eb0489272b6"
-dependencies = [
- "windows-core",
- "windows-targets",
-]
-
-[[package]]
-name = "windows-core"
-version = "0.58.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6ba6d44ec8c2591c134257ce647b7ea6b20335bf6379a27dac5f1641fcf59f99"
-dependencies = [
- "windows-implement",
- "windows-interface",
- "windows-result",
- "windows-strings",
- "windows-targets",
-]
-
-[[package]]
-name = "windows-implement"
-version = "0.58.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2bbd5b46c938e506ecbce286b6628a02171d56153ba733b6c741fc627ec9579b"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn",
-]
-
-[[package]]
-name = "windows-interface"
-version = "0.58.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "053c4c462dc91d3b1504c6fe5a726dd15e216ba718e84a0e46a88fbe5ded3515"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn",
-]
-
 [[package]]
 name = "windows-link"
 version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f0805222e57f7521d6a62e36fa9163bc891acd422f971defe97d64e70d0a4fe5"
 
-[[package]]
-name = "windows-result"
-version = "0.2.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1d1043d8214f791817bab27572aaa8af63732e11bf84aa21a45a78d6c317ae0e"
-dependencies = [
- "windows-targets",
-]
-
-[[package]]
-name = "windows-strings"
-version = "0.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4cd9b125c486025df0eabcb585e62173c6c9eddcec5d117d3b6e8c30e2ee4d10"
-dependencies = [
- "windows-result",
- "windows-targets",
-]
-
 [[package]]
 name = "windows-sys"
 version = "0.52.0"
@@ -1982,9 +2436,9 @@ dependencies = [
  "libc",
  "memmap2",
  "ndk",
- "objc2",
- "objc2-app-kit",
- "objc2-foundation",
+ "objc2 0.5.2",
+ "objc2-app-kit 0.2.2",
+ "objc2-foundation 0.2.2",
  "objc2-ui-kit",
  "orbclient",
  "percent-encoding",
@@ -2026,12 +2480,6 @@ version = "0.57.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1ebf944e87a7c253233ad6766e082e3cd714b5d03812acc24c318f549614536e"
 
-[[package]]
-name = "writeable"
-version = "0.5.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1e9df38ee2d2c3c5948ea468a8406ff0db0b29ae1ffde1bcf20ef305bcc95c51"
-
 [[package]]
 name = "x11-dl"
 version = "2.21.0"
@@ -2064,6 +2512,16 @@ version = "0.13.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ea6fc2961e4ef194dcbfe56bb845534d0dc8098940c7e5c012a258bfec6701bd"
 
+[[package]]
+name = "xattr"
+version = "1.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "32e45ad4206f6d2479085147f02bc2ef834ac85886624a23575ae137c8aa8156"
+dependencies = [
+ "libc",
+ "rustix 1.1.4",
+]
+
 [[package]]
 name = "xcursor"
 version = "0.3.10"
@@ -2089,6 +2547,12 @@ version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b9cc00251562a284751c9973bace760d86c0276c471b4be569fe6b068ee97a56"
 
+[[package]]
+name = "xml-rs"
+version = "0.8.28"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3ae8337f8a065cfc972643663ea4279e04e7256de865aa66fe25cec5fb912d3f"
+
 [[package]]
 name = "zerocopy"
 version = "0.8.48"
diff --git a/Cargo.toml b/Cargo.toml
index 10d4a0fda..657de2a59 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,6 +6,7 @@ resolver = "2"
 members = ["crates/*"]
 exclude = [
     "vendor/agent",
+    "vendor/jian",
     "node_modules",
 ]
 
diff --git a/crates/openpencil-shell-core/Cargo.toml b/crates/openpencil-shell-core/Cargo.toml
index 38b1df2d2..7a3b9e990 100644
--- a/crates/openpencil-shell-core/Cargo.toml
+++ b/crates/openpencil-shell-core/Cargo.toml
@@ -4,7 +4,7 @@ version.workspace = true
 edition.workspace = true
 rust-version.workspace = true
 license.workspace = true
-description = "OpenPencil shell — retained-mode widget tree, RenderBackend trait, parley + taffy (kickoff spec §1.2)"
+description = "OpenPencil shell — platform-agnostic widget facade + RenderBackend trait, Jian re-export wrapper (spec v19 §1.2 / §5.2)"
 
 [lib]
 name = "openpencil_shell_core"
@@ -12,11 +12,18 @@ path = "src/lib.rs"
 
 [dependencies]
 serde = { workspace = true, optional = true }
+thiserror = { workspace = true }
+tracing = { workspace = true }
 
-# Pinned per Task 0.4 wasm32 feature matrix verdict
-# (notes/2026-05-02-parley-wasm-feature-matrix.md "## 结论" 段)
-parley = { version = "0.2", default-features = false, features = ["std"] }
-taffy = { version = "0.6", default-features = false, features = ["std", "taffy_tree", "flexbox", "grid", "block_layout", "content_size"] }
+# v19 pivot: glam Vec2 用作 Point2D；bitflags 用于 widget facade 内部 flag。
+glam = { version = "0.29", default-features = false, features = ["std"] }
+bitflags = "2"
+
+# v19 pivot: re-export Jian render/geometry/scene types (spec §5.2 widget-facing facade
+# wraps jian-core; native-only deps live in shell-native, jian-core itself is wasm32-clean).
+# 双写 path + version per spec §12.2 ("path dep with explicit version") —— 防 cargo
+# 在不同 workspace context 下因 version 不一致退化到错版本。
+jian-core = { path = "../../vendor/jian/crates/jian-core", version = "0.0.1" }
 
 [features]
 default = []
diff --git a/crates/openpencil-shell-core/src/jian.rs b/crates/openpencil-shell-core/src/jian.rs
new file mode 100644
index 000000000..2a7320d9c
--- /dev/null
+++ b/crates/openpencil-shell-core/src/jian.rs
@@ -0,0 +1,41 @@
+//! Jian re-export module (spec v19 §2 / §1.2).
+//!
+//! `openpencil-shell-core` 是 Jian 薄 wrapper —— 把
+//! `jian_core::render::{DrawOp, Paint, TextRun, …}` 经 OP 层 re-export 给
+//! shell-native 内部翻译用。geometry / scene 类型加 `Jian*` 前缀，避免
+//! 与 OP 自有 `Rect` / `Color` (`render_backend.rs`) 冲突。
+//!
+//! **契约（spec §5.2.1 §746 行）**：v19 wrapper 在 NativeBackend impl 内
+//! **不让 widget code 直接看到 `jian_core::render::DrawOp`** —— widget 只
+//! 调 OP `RenderBackend` method。这些 re-export 是给 **shell-native 内部**
+//! 翻译用，不是给 widget code 用。
+
+// ────────────────────────────────────────────────────────────────────────────
+// jian_core::render —— DrawOp 命令缓冲 + Paint / TextRun / 其它绘图描述符
+// ────────────────────────────────────────────────────────────────────────────
+
+pub use jian_core::render::{
+    BorderRadii, DrawOp, GradientStop, ImageSource, LinearGradient, Paint, PathCommand,
+    RadialGradient, RenderCommand, ShadowSpec, StrokeOp, TextAlign, TextRun,
+};
+
+// ────────────────────────────────────────────────────────────────────────────
+// jian_core::geometry —— 加 Jian* 前缀避免与 OP `Rect` 冲突
+// ────────────────────────────────────────────────────────────────────────────
+
+/// Jian 的 axis-aligned 矩形 (`euclid::Rect<f32>`)。
+/// OP 自有 `crate::render_backend::Rect` 是 widget facade 用；shell-native
+/// 内部翻译时把 OP `Rect` → `JianRect`（`origin/size` → `euclid::Rect::new`）。
+pub type JianRect = jian_core::geometry::Rect;
+pub type Size = jian_core::geometry::Size;
+pub type JianPoint = jian_core::geometry::Point;
+pub type Affine2 = jian_core::geometry::Affine2;
+
+// ────────────────────────────────────────────────────────────────────────────
+// jian_core::scene —— Color (packed u32) 加 Jian* 前缀
+// ────────────────────────────────────────────────────────────────────────────
+
+/// Jian 的 packed-RGBA 颜色 (`pub struct Color(pub u32)`)；与 OP
+/// `crate::render_backend::Color` (RGBA f32 quad) 不同。NativeBackend 内部
+/// 翻译 OP Color → JianColor 时用位打包。
+pub type JianColor = jian_core::scene::Color;
diff --git a/crates/openpencil-shell-core/src/lib.rs b/crates/openpencil-shell-core/src/lib.rs
index baeb1b45d..b7c7b5329 100644
--- a/crates/openpencil-shell-core/src/lib.rs
+++ b/crates/openpencil-shell-core/src/lib.rs
@@ -1,20 +1,18 @@
-//! OpenPencil shell core — platform-agnostic widget tree + render-backend trait.
+//! OpenPencil shell core — platform-agnostic widget facade + RenderBackend trait.
 //!
-//! Per kickoff spec §1.2 (FROZEN 2026-05-02): this crate must compile on
+//! Per spec v19 §1.2 (FROZEN 2026-05-04): this crate must compile on
 //! wasm32-unknown-unknown. winit / accesskit_winit / skia-safe live in
 //! `openpencil-shell-native`; wasm-bindgen / web-sys / CanvasKit live in
 //! `openpencil-shell-web`.
+//!
+//! v19 pivot — 该 crate 是 Jian 薄 wrapper：
+//! - [`jian`] 模块 re-export `jian_core::render::{DrawOp, Paint, TextRun, …}`
+//!   + geometry/scene aliases，给 shell-native 内部翻译用（widget code 看不到）。
+//! - [`render_backend`] 模块定义 OP 自有 widget-facing facade
+//!   (`RenderBackend` trait + `Rect` / `Color` / `TextLayout`，spec §5.2)。
 
-pub fn placeholder() -> &'static str {
-    "openpencil-shell-core skeleton"
-}
+pub mod jian;
+pub mod render_backend;
 
-#[cfg(test)]
-mod tests {
-    use super::*;
-
-    #[test]
-    fn skeleton_returns_string() {
-        assert_eq!(placeholder(), "openpencil-shell-core skeleton");
-    }
-}
+// Re-export 主要 API 给上层 crate / widgets / tests 用。
+pub use render_backend::{Color, Point2D, Rect, RenderBackend, TextLayout};
diff --git a/crates/openpencil-shell-core/src/render_backend.rs b/crates/openpencil-shell-core/src/render_backend.rs
new file mode 100644
index 000000000..b6738a56a
--- /dev/null
+++ b/crates/openpencil-shell-core/src/render_backend.rs
@@ -0,0 +1,181 @@
+//! OP `RenderBackend` widget-facing facade (spec v19 §5.2).
+//!
+//! 这是 OP 的设计契约（method-style API：`fill_rect / stroke_rect / draw_text /
+//! clip_rect / save / restore / translate / resize / dpi_scale`），与 Jian
+//! `jian_core::render::RenderBackend`（command-buffer style，`new_surface /
+//! begin_frame / draw(&DrawOp)` etc.）不直接重合。
+//!
+//! 实现路径 (per §5.2.1)：
+//! - `NativeBackend` (shell-native, Step 1a 起 frame-scoped 设计)：**不**直接
+//!   impl 该 trait，而是 expose 同名 method 但带 `canvas: &skia_safe::Canvas`
+//!   显式参数。Step 1a basic_window demo 通过 `SharedSkiaContext::with_frame`
+//!   闭包内调 NativeBackend method。Step 1c+ 真接入 widget tree 时再考虑用
+//!   `WithCanvas<'a>` newtype 把 canvas 注入 trait impl。
+//! - `WebCanvasKitBackend` (shell-web, Step 1b)：内部用 CanvasKit JS binding。
+//! - `MobileBackend` (Step 1f)：内部用 Metal / Vulkan / OpenGL ES。
+//!
+//! 该模块**不**引 skia-safe / Canvas / GL 类型 —— shell-core 必须 wasm32-clean
+//! (per spec §1.2 boundary)。
+
+use jian_core::render::{TextAlign, TextRun};
+
+/// 2D 坐标点（spec §5.2 钉死 `glam::Vec2`）。
+pub type Point2D = glam::Vec2;
+
+/// 矩形（origin + size 双 Vec2 表示）。
+#[derive(Debug, Clone, Copy)]
+pub struct Rect {
+    pub origin: Point2D,
+    pub size: Point2D,
+}
+
+/// RGBA color（widget facade 层；所有分量 0.0..=1.0）。
+///
+/// 命名常量定义在 OP 这层（spec v19 round 5 CONCERN-R5-3 fix）；
+/// `jian_core::scene::Color` 是 `Color(pub u32)` packed RGBA，没有
+/// RED/BLACK/etc 命名常量，调用方用 `JianColor::rgb(...)` 显式构造。
+#[derive(Debug, Clone, Copy)]
+pub struct Color {
+    pub r: f32,
+    pub g: f32,
+    pub b: f32,
+    pub a: f32,
+}
+
+impl Color {
+    pub const RED: Self = Self {
+        r: 1.0,
+        g: 0.0,
+        b: 0.0,
+        a: 1.0,
+    };
+    pub const GREEN: Self = Self {
+        r: 0.0,
+        g: 1.0,
+        b: 0.0,
+        a: 1.0,
+    };
+    pub const BLUE: Self = Self {
+        r: 0.0,
+        g: 0.0,
+        b: 1.0,
+        a: 1.0,
+    };
+    pub const BLACK: Self = Self {
+        r: 0.0,
+        g: 0.0,
+        b: 0.0,
+        a: 1.0,
+    };
+    pub const WHITE: Self = Self {
+        r: 1.0,
+        g: 1.0,
+        b: 1.0,
+        a: 1.0,
+    };
+    pub const TRANSPARENT: Self = Self {
+        r: 0.0,
+        g: 0.0,
+        b: 0.0,
+        a: 0.0,
+    };
+}
+
+/// OP 的 TextLayout —— v19 删 parley 后定义在 OP 这层；薄薄包装
+/// `jian_core::render::TextRun`。
+///
+/// 不持 layout context / glyph cache（shell-core wasm32-clean，不能引
+/// skia/parley/icu）；真 layout 在 NativeBackend::draw_text 时通过
+/// `jian_skia::SkiaBackend` 的 textlayout feature（skia textlayout,
+/// ICU+harfbuzz）做 shape + line break。
+///
+/// Step 1a TextLayout 仅作 "已 shape 的 TextRun 集合" 占位；
+/// caret/selection/bidi/wrap 推 Step 1c+。signatures 钉死，避免后续 Step
+/// API break。
+#[derive(Debug, Clone)]
+pub struct TextLayout {
+    runs: Vec<TextRun>,
+}
+
+impl TextLayout {
+    /// 单 run 构造（Step 1a 唯一活跃路径；Phase B/C demo + raster_text_smoke 用）。
+    ///
+    /// 字段对齐 `jian_core::render::TextRun` (`vendor/jian/crates/jian-core/src/render/paint.rs:77-94`)：
+    /// **TextRun 没有 `Default` impl**，必须显式构造所有字段。
+    /// - `content` / `font_family` / `font_size` / `color` / `origin`：调用方传入
+    /// - `font_weight: 400` (CSS Normal)
+    /// - `max_width: 0.0`（"unknown; render at origin with no alignment adjustment"）
+    /// - `align: TextAlign::Start`
+    /// - `line_height: 0.0`（"default"）
+    pub fn single_run(
+        content: &str,
+        font_family: &str,
+        font_size: f32,
+        color: jian_core::scene::Color,
+        origin: Point2D,
+    ) -> Self {
+        let run = TextRun {
+            content: content.to_string(),
+            font_family: font_family.to_string(),
+            font_size,
+            font_weight: 400,
+            color,
+            origin: jian_core::geometry::Point::new(origin.x, origin.y),
+            max_width: 0.0,
+            align: TextAlign::Start,
+            line_height: 0.0,
+        };
+        Self { runs: vec![run] }
+    }
+
+    /// 已 shape 的 TextRun 集合视图。
+    pub fn runs(&self) -> &[TextRun] {
+        &self.runs
+    }
+
+    /// 平移所有 run 的 origin（NativeBackend::draw_text 在 widget origin
+    /// 基础上做平移）。返回新 layout，原 layout 不动。
+    pub fn translated(&self, offset: Point2D) -> Self {
+        let runs = self
+            .runs
+            .iter()
+            .map(|r| {
+                let mut r2 = r.clone();
+                r2.origin =
+                    jian_core::geometry::Point::new(r.origin.x + offset.x, r.origin.y + offset.y);
+                r2
+            })
+            .collect();
+        Self { runs }
+    }
+}
+
+/// Backend 抽象（widget-facing facade，spec §5.2）。
+///
+/// 注：trait 不加 `Send` bound —— skia-safe 类型 `!Send`（rust-skia
+/// thread-bound），Backend 在 render thread 内单独使用，无跨线程需求。
+///
+/// `NativeBackend` (shell-native) 在 1a **不**直接 impl 该 trait（v19 round 3
+/// BLOCK-R3-3 fix —— frame-scoped 设计避免跨帧 borrow），而是 expose 同名
+/// method 但带 `canvas: &skia_safe::Canvas` 显式参数。trait 签名内不出现任何
+/// Skia / GPU-backend 特定类型。
+pub trait RenderBackend {
+    /// Begin 帧，backend 内部维护 current frame state（不暴露 canvas 类型）。
+    fn begin_frame(&mut self);
+    fn end_frame(&mut self);
+
+    // 绘图 primitives —— widgets 调这些，不直接操作 canvas。
+    fn fill_rect(&mut self, rect: Rect, color: Color);
+    fn stroke_rect(&mut self, rect: Rect, color: Color, width: f32);
+    fn draw_text(&mut self, layout: &TextLayout, origin: Point2D);
+    fn clip_rect(&mut self, rect: Rect);
+
+    // 变换栈。
+    fn save(&mut self);
+    fn restore(&mut self);
+    fn translate(&mut self, offset: Point2D);
+
+    // viewport / dpi。
+    fn resize(&mut self, width: u32, height: u32);
+    fn dpi_scale(&self) -> f32;
+}
diff --git a/crates/openpencil-shell-core/tests/jian_re_export.rs b/crates/openpencil-shell-core/tests/jian_re_export.rs
new file mode 100644
index 000000000..5b22924c1
--- /dev/null
+++ b/crates/openpencil-shell-core/tests/jian_re_export.rs
@@ -0,0 +1,87 @@
+//! Task 1 Step 20-21: prove the Jian re-export wrapper compiles & is usable.
+//!
+//! Two anchor invariants for spec v19 §2 / §5.2：
+//! 1. `DrawOp::Rect` constructible **through OP re-export path**
+//!    (`openpencil_shell_core::jian::DrawOp` —— shell-native 内部翻译用)。
+//! 2. `TextLayout::single_run` 产生**恰好一个** `TextRun`（spec §5.2，
+//!    确认 `..Default::default()` 替代成显式字段后语义等价）。
+
+use openpencil_shell_core::jian::{DrawOp, JianRect, Paint};
+use openpencil_shell_core::render_backend::{Color, Point2D, TextLayout};
+
+#[test]
+fn drawop_rect_constructible_via_re_export() {
+    // 通过 OP re-export 路径构造 Jian DrawOp::Rect —— 证明 shell-core 的
+    // jian 模块把 jian_core::render::{DrawOp, Paint} 暴露出来了。
+    let rect = JianRect::new(
+        jian_core::geometry::Point::new(0.0, 0.0),
+        jian_core::geometry::Size::new(100.0, 50.0),
+    );
+    let paint = Paint::solid(jian_core::scene::Color::rgb(255, 0, 0));
+    let op = DrawOp::Rect { rect, paint };
+
+    match op {
+        DrawOp::Rect { rect, .. } => {
+            assert_eq!(rect.size.width, 100.0);
+            assert_eq!(rect.size.height, 50.0);
+        }
+        _ => panic!("expected DrawOp::Rect"),
+    }
+}
+
+#[test]
+fn text_layout_single_run_creates_one_run() {
+    // 显式字段构造（TextRun 没 Default impl）—— 证明 spec §5.2 的
+    // single_run 路径产生恰好一个 run，content/font_family/font_size
+    // 都按调用方传入设置。
+    let layout = TextLayout::single_run(
+        "Hello",
+        "system-ui",
+        16.0,
+        jian_core::scene::Color::rgb(0, 0, 0),
+        Point2D::new(10.0, 20.0),
+    );
+
+    assert_eq!(layout.runs().len(), 1);
+
+    let run = &layout.runs()[0];
+    assert_eq!(run.content, "Hello");
+    assert_eq!(run.font_family, "system-ui");
+    assert_eq!(run.font_size, 16.0);
+    assert_eq!(run.font_weight, 400);
+    assert_eq!(run.origin.x, 10.0);
+    assert_eq!(run.origin.y, 20.0);
+    assert_eq!(run.max_width, 0.0);
+    assert_eq!(run.line_height, 0.0);
+}
+
+#[test]
+fn text_layout_translated_offsets_origin() {
+    // translated() 把 offset 加到每 run origin 上；原 layout 不变。
+    let layout = TextLayout::single_run(
+        "World",
+        "system-ui",
+        14.0,
+        jian_core::scene::Color::rgb(0, 0, 0),
+        Point2D::new(5.0, 10.0),
+    );
+    let shifted = layout.translated(Point2D::new(100.0, 200.0));
+
+    assert_eq!(shifted.runs()[0].origin.x, 105.0);
+    assert_eq!(shifted.runs()[0].origin.y, 210.0);
+
+    // 原 layout 不动
+    assert_eq!(layout.runs()[0].origin.x, 5.0);
+    assert_eq!(layout.runs()[0].origin.y, 10.0);
+}
+
+#[test]
+fn op_color_constants_distinct() {
+    // spec §5.2 命名常量 6 全 —— RED/GREEN/BLUE/BLACK/WHITE/TRANSPARENT。
+    assert_eq!(Color::RED.r, 1.0);
+    assert_eq!(Color::GREEN.g, 1.0);
+    assert_eq!(Color::BLUE.b, 1.0);
+    assert_eq!(Color::BLACK.r, 0.0);
+    assert_eq!(Color::WHITE.r, 1.0);
+    assert_eq!(Color::TRANSPARENT.a, 0.0);
+}
diff --git a/crates/openpencil-shell-native/Cargo.toml b/crates/openpencil-shell-native/Cargo.toml
index 4b012fb3c..b12416f48 100644
--- a/crates/openpencil-shell-native/Cargo.toml
+++ b/crates/openpencil-shell-native/Cargo.toml
@@ -4,7 +4,7 @@ version.workspace = true
 edition.workspace = true
 rust-version.workspace = true
 license.workspace = true
-description = "OpenPencil shell — native (winit + skia-safe + accesskit) backend"
+description = "OpenPencil shell — native (winit + skia-safe + accesskit) backend, integrating jian-skia + jian-host-desktop sub-pieces (spec v19 §3 / §5.2.1)"
 
 [lib]
 name = "openpencil_shell_native"
@@ -17,17 +17,37 @@ openpencil-shell-core = { path = "../openpencil-shell-core", version = "0.1.0" }
 # 如果不 cfg-gate，cargo 会先 fetch + run skia-safe 的 build.rs（在 wasm32 上构建失败），
 # Step 5 grep `must NOT be compiled for wasm32` 永远命中不到——会被 skia 错误盖过。
 #
-# Phase 1 skeleton 阶段：故意保持 deps 最小，仅声明意图所需的核心 crate（winit）。
-# skia-safe / accesskit / accesskit_winit 等在 Stage F 真正实现 RenderBackend 时再加。
-# 原因：Rust 1.80 toolchain (rust-toolchain.toml) 对 home/hashbrown 等 crate 当前
-# 版本的 edition2024 / MSRV 1.81+ 需求不兼容，加完整依赖会导致下载阶段失败。
-# 详见提交说明 + Phase 1 Gate codex review。
+# v19 pivot (Task 1): 加 P0-pinned GL stack + jian-skia + jian-host-desktop。
+#   - P0 dep-stack pin 来自 P0 probe（plan v7 §Task P0；skia-safe 0.97 + glow 0.17 +
+#     glutin 0.32.3 + glutin-winit 0.5.0 + winit 0.30.13 + raw-window-handle 0.6.2 +
+#     scopeguard 1.2 全在 macOS/Windows/Linux GO）。
+#   - jian-skia (textlayout feature) 提供 SkiaBackend impl + skia textlayout（替代 parley）。
+#   - jian-host-desktop (target-gate desktop only, 不含 `run` feature) 复用 PointerTranslator /
+#     scene::collect_draws_with_state / DesktopHost config helpers；OP 自管 GPU event loop，
+#     不调 jian_host_desktop::run（softbuffer raster present 不需要）。
 #
 # winit features 说明：on Linux 必须显式开 `x11` 和/或 `wayland`，否则
-# `platform_impl/mod.rs` 触发 `compile_error!("The platform you're compiling for is
-# not supported by winit")`. macOS / Windows 各自的 backend 通过 cfg(target_os)
-# 默认启用，不需要 feature flag。Step 1a 只在三大桌面 OS 跑 CI，所以同时打开
-# x11 + wayland 两个 Linux backend 就够。Stage F 真正接 RenderBackend 时会
-# 重新审视（可能加 `serde` / `rwh_06` 等）。
+# `platform_impl/mod.rs` 触发 `compile_error!`. macOS / Windows 各自的 backend 通过
+# cfg(target_os) 默认启用，不需要 feature flag。Step 1a 三大桌面 OS CI 都跑，
+# 所以同时打开 x11 + wayland 两个 Linux backend 就够。
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
-winit = { version = "0.30", default-features = false, features = ["x11", "wayland", "wayland-csd-adwaita", "rwh_06"] }
+skia-safe = { version = "0.97.0", features = ["gl"] }
+glutin = "0.32.3"
+glutin-winit = "0.5.0"
+glow = "0.17.0"
+winit = { version = "0.30.13", default-features = false, features = ["x11", "wayland", "wayland-csd-adwaita", "rwh_06"] }
+raw-window-handle = "0.6.2"
+scopeguard = "1.2"
+
+# Jian path deps —— 双写 path + version per spec §12.2。
+# jian-skia: 提供 SkiaBackend (RenderBackend impl) + skia textlayout (textlayout feature
+# 需要 ICU + harfbuzz, ~15MB；P0.5 已升 skia-safe 0.78→0.97 + 新增 pub draw_on_canvas).
+jian-skia = { path = "../../vendor/jian/crates/jian-skia", version = "0.0.1", features = ["textlayout"] }
+
+# jian-host-desktop: target-gate desktop only (Linux/macOS/Windows)；不进 android/ios
+# metadata（Task 1 Step 26 boundary check 验证）。
+# - default-features = false：Jian 默认 features 含 `run = ["dep:softbuffer"]` 拉
+#   raster present；OP 自管 GPU event loop 不需要 softbuffer。
+# - features = ["textlayout"]：与 jian-skia 对齐文本路径。
+[target.'cfg(any(target_os = "macos", target_os = "linux", target_os = "windows"))'.dependencies]
+jian-host-desktop = { path = "../../vendor/jian/crates/jian-host-desktop", version = "0.0.1", default-features = false, features = ["textlayout"] }
diff --git a/crates/openpencil-shell-native/src/lib.rs b/crates/openpencil-shell-native/src/lib.rs
index 34447dc61..bc63d6f0d 100644
--- a/crates/openpencil-shell-native/src/lib.rs
+++ b/crates/openpencil-shell-native/src/lib.rs
@@ -1,20 +1,27 @@
 //! OpenPencil shell — native (desktop) backend.
 //!
-//! Per kickoff spec §1.2: this crate must NOT be linked into the wasm32-unknown-unknown
-//! web bundle. Even though some deps (winit) compile silently on wasm32 via web-sys,
-//! we use an explicit compile_error! guard to make accidental inclusion a hard error.
+//! Per spec v19 §1.2 (FROZEN 2026-05-04): this crate must NOT be linked into
+//! the wasm32-unknown-unknown web bundle. Even though some deps (winit) compile
+//! silently on wasm32 via web-sys, we use an explicit compile_error! guard to
+//! make accidental inclusion a hard error.
+//!
+//! Step 1a Task 1 状态：仅装 deps（P0-pinned GL stack + jian-skia +
+//! jian-host-desktop）；SharedSkiaContext / NativeBackend 实现在 Task 2 加。
 
 #[cfg(target_arch = "wasm32")]
 compile_error!(
     "openpencil-shell-native must NOT be compiled for wasm32 targets. \
-     Use openpencil-shell-web for browser builds (kickoff spec §1.2)."
+     Use openpencil-shell-web for browser builds (spec v19 §1.2)."
 );
 
-pub fn placeholder() -> String {
-    format!(
-        "openpencil-shell-native skeleton ({})",
-        openpencil_shell_core::placeholder()
-    )
+/// Skeleton placeholder until Task 2 lands `SharedSkiaContext` / `NativeBackend`.
+///
+/// 用 OP `Color::RED` 命名常量证明 shell-core re-export 链通了；这是最小
+/// link-check （Step 1a Task 1 不实现 Skia surface 与 GL provider，那些
+/// 是 Task 2 的范围）。
+pub fn placeholder() -> &'static str {
+    let _red = openpencil_shell_core::Color::RED;
+    "openpencil-shell-native skeleton (Task 1: deps wired)"
 }
 
 #[cfg(test)]
@@ -23,6 +30,6 @@ mod tests {
 
     #[test]
     fn skeleton_links_core() {
-        assert!(placeholder().contains("openpencil-shell-core"));
+        assert!(placeholder().contains("Task 1"));
     }
 }
diff --git a/crates/openpencil-shell-web/src/lib.rs b/crates/openpencil-shell-web/src/lib.rs
index a83e453b8..92b84211a 100644
--- a/crates/openpencil-shell-web/src/lib.rs
+++ b/crates/openpencil-shell-web/src/lib.rs
@@ -1,15 +1,21 @@
 //! OpenPencil shell — web (wasm32) bundle entry.
 //!
-//! Per kickoff spec §1.2: this crate is the web bundle entry. CI invariant
-//! requires `cargo check --target wasm32-unknown-unknown -p openpencil-shell-web
-//! --no-default-features --features web` to pass on every PR.
+//! Per spec v19 §1.2 (FROZEN 2026-05-04): this crate is the web bundle entry.
+//! CI invariant requires `cargo check --target wasm32-unknown-unknown -p
+//! openpencil-shell-web --no-default-features --features web` to pass on
+//! every PR.
+//!
+//! Step 1a Task 1 状态：仅 link-check shell-core re-export；CanvasKit
+//! WebBackend 在 Step 1b 加。
 
 use wasm_bindgen::prelude::*;
 
+/// Skeleton placeholder until Step 1b lands `WebCanvasKitBackend`.
+///
+/// 用 OP `Color::TRANSPARENT` 命名常量证明 shell-core re-export 在 wasm32
+/// 链通了；这是最小 link-check（shell-core 必须 wasm32-clean per spec §1.2）。
 #[wasm_bindgen]
 pub fn placeholder() -> String {
-    format!(
-        "openpencil-shell-web skeleton ({})",
-        openpencil_shell_core::placeholder()
-    )
+    let _t = openpencil_shell_core::Color::TRANSPARENT;
+    "openpencil-shell-web skeleton (Task 1: deps wired)".to_string()
 }
diff --git a/vendor/jian b/vendor/jian
new file mode 160000
index 000000000..ad13ce628
--- /dev/null
+++ b/vendor/jian
@@ -0,0 +1 @@
+Subproject commit ad13ce6283caf402e71608d362e837b09140331b