fix: make sharp module optional

packages/gatsby-plugin-manifest/package.json

@@ -1,23 +1,26 @@
 {
   "name": "gatsby-plugin-manifest",
   "description": "Gatsby plugin which adds a manifest.webmanifest to make sites progressive web apps",
-  "version": "3.3.0-next.1",
+  "version": "3.3.0",
   "author": "Kyle Mathews <mathews.kyle@gmail.com>",
   "bugs": {
     "url": "https://github.com/gatsbyjs/gatsby/issues"
   },
   "dependencies": {
     "@babel/runtime": "^7.12.5",
-    "gatsby-core-utils": "^2.3.0-next.1",
-    "gatsby-plugin-utils": "^1.3.0-next.1",
-    "semver": "^7.3.2",
+    "gatsby-core-utils": "^2.3.0",
+    "gatsby-plugin-utils": "^1.3.0",
+    "semver": "^7.3.2"
+  },
+  "optionalDependencies": {
     "sharp": "^0.28.0"
   },
   "devDependencies": {
     "@babel/cli": "^7.12.1",
     "@babel/core": "^7.12.3",
-    "babel-preset-gatsby-package": "^1.3.0-next.1",
-    "cross-env": "^7.0.3"
+    "babel-preset-gatsby-package": "^1.3.0",
+    "cross-env": "^7.0.3",
+    "sharp": "^0.28.0"
   },
   "homepage": "https://github.com/gatsbyjs/gatsby/tree/master/packages/gatsby-plugin-manifest#readme",
   "keywords": [
@@ -32,7 +35,7 @@
   "license": "MIT",
   "main": "index.js",
   "peerDependencies": {
-    "gatsby": "^3.0.0-next.0"
+    "gatsby": "^3.0.0"
   },
   "repository": {
     "type": "git",

packages/gatsby-plugin-manifest/src/gatsby-node.js

@@ -1,13 +1,20 @@
 import * as fs from "fs"
 import * as path from "path"
-import sharp from "./safe-sharp"
 import { createContentDigest, cpuCoreCount, slash } from "gatsby-core-utils"
 import { defaultIcons, addDigestToPath, favicons } from "./common"
 import { doesIconExist } from "./node-helpers"
 
 import pluginOptionsSchema from "./pluginOptionsSchema"
 
-sharp.simd(true)
+let sharp
+function getSharp() {
+  // import sharp lazily
+  if (!sharp) {
+    sharp = require(`./safe-sharp`)
+    sharp.simd(true)
+  }
+  return sharp
+}
 
 // Handle Sharp's concurrency based on the Gatsby CPU count
 // See: http://sharp.pixelplumbing.com/en/stable/api-utility/#concurrency
@@ -30,7 +37,7 @@ async function generateIcon(icon, srcIcon) {
   // Sharp accept density from 1 to 2400
   const density = Math.min(2400, Math.max(1, size))
 
-  return sharp(srcIcon, { density })
+  return getSharp()(srcIcon, { density })
     .resize({
       width: size,
       height: size,
@@ -195,7 +202,7 @@ const makeManifest = async ({
       )
     }
 
-    const sharpIcon = sharp(icon)
+    const sharpIcon = getSharp()(icon)
 
     const metadata = await sharpIcon.metadata()