diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 13787f219..be1409317 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -64,10 +64,18 @@ jobs:
       - run: bun install --frozen-lockfile
       - name: Install cross-platform native bindings
         run: |
-          bun install --os darwin --cpu arm64
-          bun install --os darwin --cpu x64
-          bun install --os linux --cpu arm64
-          bun install --os win32 --cpu x64
+          # bun install only fetches optional deps for current platform (linux-x64)
+          # Explicitly install all platform binaries for bun cross-compilation
+          bun add --no-save \
+            @img/sharp-darwin-arm64@0.34.5 \
+            @img/sharp-darwin-x64@0.34.5 \
+            @img/sharp-linux-x64@0.34.5 \
+            @img/sharp-linux-arm64@0.34.5 \
+            @img/sharp-win32-x64@0.34.5 \
+            @img/sharp-libvips-darwin-arm64@1.2.4 \
+            @img/sharp-libvips-darwin-x64@1.2.4 \
+            @img/sharp-libvips-linux-x64@1.2.4 \
+            @img/sharp-libvips-linux-arm64@1.2.4
       - name: Build binaries
         run: |
           cd packages/coding-agent
diff --git a/bun.lock b/bun.lock
index 327e0e468..fe043b86b 100644
--- a/bun.lock
+++ b/bun.lock
@@ -83,7 +83,6 @@
         "nanoid": "^5.1.6",
         "ndjson": "^2.0.0",
         "node-html-parser": "^6.1.13",
-        "sharp": "^0.34.2",
         "smol-toml": "^1.6.0",
         "strip-ansi": "^7.1.2",
         "winston": "^3.17.0",
@@ -97,6 +96,9 @@
         "@types/node": "^24.3.0",
         "ms": "^2.1.3",
       },
+      "optionalDependencies": {
+        "sharp": "^0.34.2",
+      },
     },
     "packages/git-tool": {
       "name": "@oh-my-pi/pi-git-tool",
diff --git a/packages/coding-agent/CHANGELOG.md b/packages/coding-agent/CHANGELOG.md
index 67177a463..02e6ac264 100644
--- a/packages/coding-agent/CHANGELOG.md
+++ b/packages/coding-agent/CHANGELOG.md
@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Fixed
+
+- Move `sharp` to optional dependencies with all platform binaries to fix arm64 runtime errors
+
 ## [4.7.0] - 2026-01-12
 ### Added
 
diff --git a/packages/coding-agent/package.json b/packages/coding-agent/package.json
index 61c227594..2855a6ac5 100644
--- a/packages/coding-agent/package.json
+++ b/packages/coding-agent/package.json
@@ -58,7 +58,7 @@
 		"nanoid": "^5.1.6",
 		"ndjson": "^2.0.0",
 		"node-html-parser": "^6.1.13",
-		"sharp": "^0.34.2",
+		
 		"smol-toml": "^1.6.0",
 		"strip-ansi": "^7.1.2",
 		"winston": "^3.17.0",
@@ -72,6 +72,9 @@
 		"@types/node": "^24.3.0",
 		"ms": "^2.1.3"
 	},
+	"optionalDependencies": {
+		"sharp": "^0.34.2"
+	},
 	"keywords": [
 		"coding-agent",
 		"ai",