diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 069fb9a..cdb468c 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -92,3 +92,81 @@ jobs:
             ${{ runner.os }}-cargo-min-
       - name: Build default feature set
         run: cargo build --workspace
+
+  build-wasm:
+    name: Build WebAssembly (Emscripten)
+    runs-on: ubuntu-latest
+    timeout-minutes: 30
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+
+      - name: Set up Rust toolchain
+        uses: dtolnay/rust-toolchain@stable
+        with:
+          targets: wasm32-unknown-emscripten
+
+      - name: Install Emscripten
+        uses: mymindstorm/setup-emsdk@v14
+        with:
+          # Pin to 3.1.x: Skia's pre-built wasm binaries use emscripten-style
+          # exception handling (invoke_* wrappers). Emscripten 4.x defaults to
+          # wasm-native exceptions (-fwasm-exceptions) which is incompatible.
+          version: '3.1.74'
+          actions-cache-folder: 'emsdk-cache'
+
+      - name: Cache cargo registry + git + build
+        uses: actions/cache@v4
+        with:
+          path: |
+            ~/.cargo/registry
+            ~/.cargo/git
+            target
+          key: ${{ runner.os }}-cargo-wasm-emsdk3.1.74-${{ hashFiles('**/Cargo.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-cargo-wasm-emsdk3.1.74-
+
+      - name: Build xtask
+        run: cargo build -p xtask
+
+      - name: Build WASM with xtask
+        run: cargo xtask emscripten --features skia-wasm --emsdk $EMSDK
+
+      - name: Prepare deployment artifacts
+        run: |
+          mkdir -p deploy
+          cp examples/web/index.html deploy/
+          cp examples/web/dist/emscripten.js deploy/
+          cp examples/web/dist/emscripten.wasm deploy/
+
+      - name: Upload Pages artifact
+        uses: actions/upload-pages-artifact@v3
+        with:
+          path: deploy
+
+  deploy:
+    name: Deploy to GitHub Pages
+    runs-on: ubuntu-latest
+    needs: [test, minimal, build-wasm]
+    # Only deploy on push to main (not on PRs)
+    if: github.event_name == 'push' && github.ref == 'refs/heads/main'
+
+    # Allow only one concurrent deployment, skipping runs queued between the run in-progress and latest queued.
+    # However, do NOT cancel in-progress runs as we want to allow these production deployments to complete.
+    concurrency:
+      group: "pages"
+      cancel-in-progress: false
+
+    permissions:
+      pages: write
+      id-token: write
+
+    environment:
+      name: github-pages
+      url: ${{ steps.deployment.outputs.page_url }}
+
+    steps:
+      - name: Deploy to GitHub Pages
+        id: deployment
+        uses: actions/deploy-pages@v4
diff --git a/xtask/src/main.rs b/xtask/src/main.rs
index 64ee131..f8d7e2d 100644
--- a/xtask/src/main.rs
+++ b/xtask/src/main.rs
@@ -118,7 +118,9 @@ fn build_emscripten(
     // Check emsdk exists
     let emsdk_path = get_emsdk_path(emsdk_override)?;
 
-    // Set EMCC_CFLAGS
+    // Set EMCC_CFLAGS (applies to every emcc invocation: compile + link).
+    // SUPPORT_LONGJMP must be set explicitly — the emscripten default does
+    // not propagate when emcc is invoked as a linker through rustc's driver.
     let emcc_cflags = [
         "--no-entry",
         "-sASSERTIONS=1",
@@ -127,6 +129,7 @@ fn build_emscripten(
         "-sENVIRONMENT=web",
         "-sERROR_ON_UNDEFINED_SYMBOLS=0",
         "-sMAX_WEBGL_VERSION=2",
+        "-sSUPPORT_LONGJMP=emscripten",
     ]
     .join(" ");
 
@@ -135,6 +138,7 @@ fn build_emscripten(
         "-C link-args=-sEXPORTED_FUNCTIONS=['_sk_load_pdf','_sk_get_page_count','_sk_render_page','_sk_free_pdf','_malloc','_free']",
         "-C link-args=-sEXPORTED_RUNTIME_METHODS=['cwrap','HEAPU8']",
         "-C link-args=-sSTANDALONE_WASM=0",
+        "-C link-args=-sSUPPORT_LONGJMP=emscripten",
     ]
     .join(" ");
 
@@ -173,7 +177,10 @@ fn build_emscripten(
         .arg("cargo")
         .args(&cargo_args)
         .env("EMCC_CFLAGS", emcc_cflags)
-        .env("RUSTFLAGS", rustflags)
+        .env(
+            "CARGO_TARGET_WASM32_UNKNOWN_EMSCRIPTEN_RUSTFLAGS",
+            rustflags,
+        )
         .stdout(Stdio::inherit())
         .stderr(Stdio::inherit())
         .status()