diff --git a/codecs/imagequant/package.json b/codecs/imagequant/package.json
index e3d67582..b4f053f3 100644
--- a/codecs/imagequant/package.json
+++ b/codecs/imagequant/package.json
@@ -8,6 +8,6 @@
     "libimagequant": "ImageOptim/libimagequant#2.12.1"
   },
   "devDependencies": {
-    "napa": "^3.0.0"
+    "napa": "3.0.0"
   }
 }
diff --git a/codecs/mozjpeg_enc/package.json b/codecs/mozjpeg_enc/package.json
index 549b8589..8e98826d 100644
--- a/codecs/mozjpeg_enc/package.json
+++ b/codecs/mozjpeg_enc/package.json
@@ -8,6 +8,6 @@
     "mozjpeg": "mozilla/mozjpeg#v3.3.1"
   },
   "devDependencies": {
-    "napa": "^3.0.0"
+    "napa": "3.0.0"
   }
 }
diff --git a/codecs/optipng/package.json b/codecs/optipng/package.json
index 3b34fe51..f61264b1 100644
--- a/codecs/optipng/package.json
+++ b/codecs/optipng/package.json
@@ -16,7 +16,7 @@
     "zlib": "emscripten-ports/zlib"
   },
   "dependencies": {
-    "napa": "^3.0.0",
+    "napa": "3.0.0",
     "tar-dependency": "0.0.3"
   }
 }
diff --git a/codecs/webp_dec/package.json b/codecs/webp_dec/package.json
index 6220ba6a..c9253fec 100644
--- a/codecs/webp_dec/package.json
+++ b/codecs/webp_dec/package.json
@@ -8,6 +8,6 @@
     "libwebp": "webmproject/libwebp#v1.0.0"
   },
   "devDependencies": {
-    "napa": "^3.0.0"
+    "napa": "3.0.0"
   }
 }
diff --git a/codecs/webp_enc/package.json b/codecs/webp_enc/package.json
index c467bf23..f1f753d4 100644
--- a/codecs/webp_enc/package.json
+++ b/codecs/webp_enc/package.json
@@ -8,6 +8,6 @@
     "libwebp": "webmproject/libwebp#v1.0.0"
   },
   "devDependencies": {
-    "napa": "^3.0.0"
+    "napa": "3.0.0"
   }
 }
diff --git a/package-lock.json b/package-lock.json
index 7c386c5f..b667bacf 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -5153,12 +5153,14 @@
         "balanced-match": {
           "version": "1.0.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "brace-expansion": {
           "version": "1.1.11",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "balanced-match": "^1.0.0",
             "concat-map": "0.0.1"
@@ -5173,17 +5175,20 @@
         "code-point-at": {
           "version": "1.1.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "concat-map": {
           "version": "0.0.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "console-control-strings": {
           "version": "1.1.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "core-util-is": {
           "version": "1.0.2",
@@ -5300,7 +5305,8 @@
         "inherits": {
           "version": "2.0.3",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "ini": {
           "version": "1.3.5",
@@ -5312,6 +5318,7 @@
           "version": "1.0.0",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "number-is-nan": "^1.0.0"
           }
@@ -5326,6 +5333,7 @@
           "version": "3.0.4",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "brace-expansion": "^1.1.7"
           }
@@ -5333,12 +5341,14 @@
         "minimist": {
           "version": "0.0.8",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "minipass": {
           "version": "2.2.4",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "safe-buffer": "^5.1.1",
             "yallist": "^3.0.0"
@@ -5357,6 +5367,7 @@
           "version": "0.5.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "minimist": "0.0.8"
           }
@@ -5437,7 +5448,8 @@
         "number-is-nan": {
           "version": "1.0.1",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "object-assign": {
           "version": "4.1.1",
@@ -5449,6 +5461,7 @@
           "version": "1.4.0",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "wrappy": "1"
           }
@@ -5570,6 +5583,7 @@
           "version": "1.0.2",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "code-point-at": "^1.0.0",
             "is-fullwidth-code-point": "^1.0.0",
diff --git a/package.json b/package.json
index 90bee562..a49cd1f6 100644
--- a/package.json
+++ b/package.json
@@ -15,55 +15,55 @@
     }
   },
   "devDependencies": {
-    "@types/node": "^10.12.6",
-    "@types/pretty-bytes": "^5.1.0",
+    "@types/node": "10.12.6",
+    "@types/pretty-bytes": "5.1.0",
     "@types/webassembly-js-api": "0.0.1",
-    "@webcomponents/custom-elements": "^1.2.1",
-    "@webpack-cli/serve": "^0.1.2",
-    "assets-webpack-plugin": "^3.9.7",
-    "chokidar": "^2.0.4",
-    "classnames": "^2.2.6",
-    "clean-webpack-plugin": "^1.0.0",
-    "comlink": "^3.0.3",
-    "copy-webpack-plugin": "^4.6.0",
-    "critters-webpack-plugin": "^2.0.1",
-    "css-loader": "^1.0.1",
-    "ejs": "^2.6.1",
-    "exports-loader": "^0.7.0",
-    "file-drop-element": "^0.0.9",
-    "file-loader": "^2.0.0",
-    "html-webpack-plugin": "^3.2.0",
-    "husky": "^1.1.4",
-    "idb-keyval": "^3.1.0",
-    "linkstate": "^1.1.1",
-    "loader-utils": "^1.1.0",
-    "mini-css-extract-plugin": "^0.4.4",
-    "minimatch": "^3.0.4",
-    "node-sass": "^4.11.0",
-    "optimize-css-assets-webpack-plugin": "^5.0.1",
-    "pointer-tracker": "^2.0.3",
-    "preact": "^8.3.1",
-    "prerender-loader": "^1.2.0",
-    "pretty-bytes": "^5.1.0",
-    "progress-bar-webpack-plugin": "^1.11.0",
-    "raw-loader": "^0.5.1",
-    "sass-loader": "^7.1.0",
-    "script-ext-html-webpack-plugin": "^2.1.3",
-    "source-map-loader": "^0.2.4",
-    "style-loader": "^0.23.1",
-    "terser-webpack-plugin": "^1.1.0",
-    "ts-loader": "^5.3.0",
-    "tslint": "^5.11.0",
-    "tslint-config-airbnb": "^5.11.0",
-    "tslint-config-semistandard": "^7.0.0",
-    "tslint-react": "^3.6.0",
-    "typed-css-modules": "^0.3.7",
-    "typescript": "^3.1.6",
-    "url-loader": "^1.1.2",
-    "webpack": "^4.25.1",
-    "webpack-bundle-analyzer": "^3.0.3",
-    "webpack-cli": "^3.1.2",
-    "webpack-dev-server": "^3.1.10",
-    "worker-plugin": "^1.1.1"
+    "@webcomponents/custom-elements": "1.2.1",
+    "@webpack-cli/serve": "0.1.2",
+    "assets-webpack-plugin": "3.9.7",
+    "chokidar": "2.0.4",
+    "classnames": "2.2.6",
+    "clean-webpack-plugin": "1.0.0",
+    "comlink": "3.0.3",
+    "copy-webpack-plugin": "4.6.0",
+    "critters-webpack-plugin": "2.0.1",
+    "css-loader": "1.0.1",
+    "ejs": "2.6.1",
+    "exports-loader": "0.7.0",
+    "file-drop-element": "0.0.9",
+    "file-loader": "2.0.0",
+    "html-webpack-plugin": "3.2.0",
+    "husky": "1.1.4",
+    "idb-keyval": "3.1.0",
+    "linkstate": "1.1.1",
+    "loader-utils": "1.1.0",
+    "mini-css-extract-plugin": "0.4.4",
+    "minimatch": "3.0.4",
+    "node-sass": "4.11.0",
+    "optimize-css-assets-webpack-plugin": "5.0.1",
+    "pointer-tracker": "2.0.3",
+    "preact": "8.3.1",
+    "prerender-loader": "1.2.0",
+    "pretty-bytes": "5.1.0",
+    "progress-bar-webpack-plugin": "1.11.0",
+    "raw-loader": "0.5.1",
+    "sass-loader": "7.1.0",
+    "script-ext-html-webpack-plugin": "2.1.3",
+    "source-map-loader": "0.2.4",
+    "style-loader": "0.23.1",
+    "terser-webpack-plugin": "1.1.0",
+    "ts-loader": "5.3.0",
+    "tslint": "5.11.0",
+    "tslint-config-airbnb": "5.11.0",
+    "tslint-config-semistandard": "7.0.0",
+    "tslint-react": "3.6.0",
+    "typed-css-modules": "0.3.7",
+    "typescript": "3.1.6",
+    "url-loader": "1.1.2",
+    "webpack": "4.25.1",
+    "webpack-bundle-analyzer": "3.0.3",
+    "webpack-cli": "3.1.2",
+    "webpack-dev-server": "3.1.10",
+    "worker-plugin": "1.1.1"
   }
 }