diff --git a/lib/summarize.js b/lib/summarize.js
index 7c24a18..23c3f1a 100644
--- a/lib/summarize.js
+++ b/lib/summarize.js
@@ -6,15 +6,9 @@ const Terser = require('terser');
 const zlib = require('zlib');
 const pify = require('pify');
 
-function uglify(content) {
-  return new Promise((resolve, reject) => {
-    let uglified = Terser.minify(content);
-    if (uglified.error) {
-      reject(uglified.error);
-    } else {
-      resolve(uglified.code);
-    }
-  });
+async function uglify(content) {
+  const { code } = await Terser.minify(content);
+  return code;
 }
 
 function compress(content) {
diff --git a/package.json b/package.json
index c55914f..248145a 100644
--- a/package.json
+++ b/package.json
@@ -24,9 +24,9 @@
     "fs-extra": "^9.0.1",
     "ora": "^5.1.0",
     "pify": "^5.0.0",
-    "terser": "^3.10.11",
+    "terser": "^5.3.7",
     "walk-sync": "^2.2.0",
-    "workerpool": "^6.0.1",
+    "workerpool": "^6.0.2",
     "zlib": "^1.0.5"
   },
   "devDependencies": {
diff --git a/test/acceptance/__snapshots__/cli.test.js.snap b/test/acceptance/__snapshots__/cli.test.js.snap
index 108d3af..6c9fabf 100644
--- a/test/acceptance/__snapshots__/cli.test.js.snap
+++ b/test/acceptance/__snapshots__/cli.test.js.snap
@@ -8,56 +8,56 @@ exports[`CLI generates expected output 1`] = `
       \\"relativePath\\": \\"test-app/app.js\\",
       \\"sizes\\": {
         \\"raw\\": 606,
-        \\"uglified\\": 375,
-        \\"compressed\\": 119.82860520094562
+        \\"uglified\\": 377,
+        \\"compressed\\": 120.451057165231
       }
     },
     {
       \\"relativePath\\": \\"test-app/initializers/app-version.js\\",
       \\"sizes\\": {
         \\"raw\\": 510,
-        \\"uglified\\": 311,
-        \\"compressed\\": 99.37785657998424
+        \\"uglified\\": 313,
+        \\"compressed\\": 100.00313234142521
       }
     },
     {
       \\"relativePath\\": \\"test-app/initializers/container-debug-adapter.js\\",
       \\"sizes\\": {
         \\"raw\\": 590,
-        \\"uglified\\": 428,
-        \\"compressed\\": 136.76438140267928
+        \\"uglified\\": 430,
+        \\"compressed\\": 137.38449490994518
       }
     },
     {
       \\"relativePath\\": \\"test-app/initializers/export-application-global.js\\",
       \\"sizes\\": {
         \\"raw\\": 1377,
-        \\"uglified\\": 684,
-        \\"compressed\\": 218.56737588652481
+        \\"uglified\\": 686,
+        \\"compressed\\": 219.17619420516837
       }
     },
     {
       \\"relativePath\\": \\"test-app/resolver.js\\",
       \\"sizes\\": {
         \\"raw\\": 231,
-        \\"uglified\\": 154,
-        \\"compressed\\": 49.20961386918834
+        \\"uglified\\": 156,
+        \\"compressed\\": 49.841816758026624
       }
     },
     {
       \\"relativePath\\": \\"test-app/router.js\\",
       \\"sizes\\": {
         \\"raw\\": 425,
-        \\"uglified\\": 264,
-        \\"compressed\\": 84.35933806146572
+        \\"uglified\\": 268,
+        \\"compressed\\": 85.62568519968676
       }
     },
     {
       \\"relativePath\\": \\"test-app/templates/application.js\\",
       \\"sizes\\": {
         \\"raw\\": 399,
-        \\"uglified\\": 322,
-        \\"compressed\\": 102.89282899921197
+        \\"uglified\\": 324,
+        \\"compressed\\": 103.51761942051684
       }
     }
   ]
diff --git a/test/integration/__snapshots__/summarize.test.js.snap b/test/integration/__snapshots__/summarize.test.js.snap
index 0f992fa..6bec0c6 100644
--- a/test/integration/__snapshots__/summarize.test.js.snap
+++ b/test/integration/__snapshots__/summarize.test.js.snap
@@ -8,56 +8,56 @@ exports[`summarize summarize calculates sizes 1`] = `
       \\"relativePath\\": \\"test-app/app.js\\",
       \\"sizes\\": {
         \\"raw\\": 606,
-        \\"uglified\\": 375,
-        \\"compressed\\": 119.82860520094562
+        \\"uglified\\": 377,
+        \\"compressed\\": 120.451057165231
       }
     },
     {
       \\"relativePath\\": \\"test-app/initializers/app-version.js\\",
       \\"sizes\\": {
         \\"raw\\": 510,
-        \\"uglified\\": 311,
-        \\"compressed\\": 99.37785657998424
+        \\"uglified\\": 313,
+        \\"compressed\\": 100.00313234142521
       }
     },
     {
       \\"relativePath\\": \\"test-app/initializers/container-debug-adapter.js\\",
       \\"sizes\\": {
         \\"raw\\": 590,
-        \\"uglified\\": 428,
-        \\"compressed\\": 136.76438140267928
+        \\"uglified\\": 430,
+        \\"compressed\\": 137.38449490994518
       }
     },
     {
       \\"relativePath\\": \\"test-app/initializers/export-application-global.js\\",
       \\"sizes\\": {
         \\"raw\\": 1377,
-        \\"uglified\\": 684,
-        \\"compressed\\": 218.56737588652481
+        \\"uglified\\": 686,
+        \\"compressed\\": 219.17619420516837
       }
     },
     {
       \\"relativePath\\": \\"test-app/resolver.js\\",
       \\"sizes\\": {
         \\"raw\\": 231,
-        \\"uglified\\": 154,
-        \\"compressed\\": 49.20961386918834
+        \\"uglified\\": 156,
+        \\"compressed\\": 49.841816758026624
       }
     },
     {
       \\"relativePath\\": \\"test-app/router.js\\",
       \\"sizes\\": {
         \\"raw\\": 425,
-        \\"uglified\\": 264,
-        \\"compressed\\": 84.35933806146572
+        \\"uglified\\": 268,
+        \\"compressed\\": 85.62568519968676
       }
     },
     {
       \\"relativePath\\": \\"test-app/templates/application.js\\",
       \\"sizes\\": {
         \\"raw\\": 399,
-        \\"uglified\\": 322,
-        \\"compressed\\": 102.89282899921197
+        \\"uglified\\": 324,
+        \\"compressed\\": 103.51761942051684
       }
     }
   ]
@@ -72,56 +72,56 @@ exports[`summarize summarize-all calculates sizes of all files 1`] = `
       \\"relativePath\\": \\"test-app/app.js\\",
       \\"sizes\\": {
         \\"raw\\": 606,
-        \\"uglified\\": 375,
-        \\"compressed\\": 119.82860520094562
+        \\"uglified\\": 377,
+        \\"compressed\\": 120.451057165231
       }
     },
     {
       \\"relativePath\\": \\"test-app/initializers/app-version.js\\",
       \\"sizes\\": {
         \\"raw\\": 510,
-        \\"uglified\\": 311,
-        \\"compressed\\": 99.37785657998424
+        \\"uglified\\": 313,
+        \\"compressed\\": 100.00313234142521
       }
     },
     {
       \\"relativePath\\": \\"test-app/initializers/container-debug-adapter.js\\",
       \\"sizes\\": {
         \\"raw\\": 590,
-        \\"uglified\\": 428,
-        \\"compressed\\": 136.76438140267928
+        \\"uglified\\": 430,
+        \\"compressed\\": 137.38449490994518
       }
     },
     {
       \\"relativePath\\": \\"test-app/initializers/export-application-global.js\\",
       \\"sizes\\": {
         \\"raw\\": 1377,
-        \\"uglified\\": 684,
-        \\"compressed\\": 218.56737588652481
+        \\"uglified\\": 686,
+        \\"compressed\\": 219.17619420516837
       }
     },
     {
       \\"relativePath\\": \\"test-app/resolver.js\\",
       \\"sizes\\": {
         \\"raw\\": 231,
-        \\"uglified\\": 154,
-        \\"compressed\\": 49.20961386918834
+        \\"uglified\\": 156,
+        \\"compressed\\": 49.841816758026624
       }
     },
     {
       \\"relativePath\\": \\"test-app/router.js\\",
       \\"sizes\\": {
         \\"raw\\": 425,
-        \\"uglified\\": 264,
-        \\"compressed\\": 84.35933806146572
+        \\"uglified\\": 268,
+        \\"compressed\\": 85.62568519968676
       }
     },
     {
       \\"relativePath\\": \\"test-app/templates/application.js\\",
       \\"sizes\\": {
         \\"raw\\": 399,
-        \\"uglified\\": 322,
-        \\"compressed\\": 102.89282899921197
+        \\"uglified\\": 324,
+        \\"compressed\\": 103.51761942051684
       }
     }
   ]
@@ -165,56 +165,56 @@ exports[`summarize summarize-all can ignore files 1`] = `
       \\"relativePath\\": \\"test-app/app.js\\",
       \\"sizes\\": {
         \\"raw\\": 606,
-        \\"uglified\\": 375,
-        \\"compressed\\": 119.82860520094562
+        \\"uglified\\": 377,
+        \\"compressed\\": 120.451057165231
       }
     },
     {
       \\"relativePath\\": \\"test-app/initializers/app-version.js\\",
       \\"sizes\\": {
         \\"raw\\": 510,
-        \\"uglified\\": 311,
-        \\"compressed\\": 99.37785657998424
+        \\"uglified\\": 313,
+        \\"compressed\\": 100.00313234142521
       }
     },
     {
       \\"relativePath\\": \\"test-app/initializers/container-debug-adapter.js\\",
       \\"sizes\\": {
         \\"raw\\": 590,
-        \\"uglified\\": 428,
-        \\"compressed\\": 136.76438140267928
+        \\"uglified\\": 430,
+        \\"compressed\\": 137.38449490994518
       }
     },
     {
       \\"relativePath\\": \\"test-app/initializers/export-application-global.js\\",
       \\"sizes\\": {
         \\"raw\\": 1377,
-        \\"uglified\\": 684,
-        \\"compressed\\": 218.56737588652481
+        \\"uglified\\": 686,
+        \\"compressed\\": 219.17619420516837
       }
     },
     {
       \\"relativePath\\": \\"test-app/resolver.js\\",
       \\"sizes\\": {
         \\"raw\\": 231,
-        \\"uglified\\": 154,
-        \\"compressed\\": 49.20961386918834
+        \\"uglified\\": 156,
+        \\"compressed\\": 49.841816758026624
       }
     },
     {
       \\"relativePath\\": \\"test-app/router.js\\",
       \\"sizes\\": {
         \\"raw\\": 425,
-        \\"uglified\\": 264,
-        \\"compressed\\": 84.35933806146572
+        \\"uglified\\": 268,
+        \\"compressed\\": 85.62568519968676
       }
     },
     {
       \\"relativePath\\": \\"test-app/templates/application.js\\",
       \\"sizes\\": {
         \\"raw\\": 399,
-        \\"uglified\\": 322,
-        \\"compressed\\": 102.89282899921197
+        \\"uglified\\": 324,
+        \\"compressed\\": 103.51761942051684
       }
     }
   ]
diff --git a/yarn.lock b/yarn.lock
index 5abad4a..5282ff9 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1157,7 +1157,7 @@ combined-stream@^1.0.6, combined-stream@~1.0.6:
   dependencies:
     delayed-stream "~1.0.0"
 
-commander@^2.19.0:
+commander@^2.20.0:
   version "2.20.3"
   resolved "https://registry.yarnpkg.com/commander/-/commander-2.20.3.tgz#fd485e84c03eb4881c20722ba48035e8531aeb33"
   integrity sha512-GpVkmM8vF2vQUkj2LvZmD35JxeJOLCwJ9cUkugyk2nuhbv3+mJvpLYYt+0+USMxE+oj+ey/lJEnhZw75x/OMcQ==
@@ -3973,7 +3973,7 @@ source-map-resolve@^0.5.0:
     source-map-url "^0.4.0"
     urix "^0.1.0"
 
-source-map-support@^0.5.6, source-map-support@~0.5.10:
+source-map-support@^0.5.6, source-map-support@~0.5.19:
   version "0.5.19"
   resolved "https://registry.yarnpkg.com/source-map-support/-/source-map-support-0.5.19.tgz#a98b62f86dcaf4f67399648c085291ab9e8fed61"
   integrity sha512-Wonm7zOCIJzBGQdB+thsPar0kYuCIzYvxZwlBa87yi/Mdjv7Tip2cyVbLj5o0cFPN4EVkuTwb3GDDyUx2DGnGw==
@@ -3996,7 +3996,7 @@ source-map@^0.6.0, source-map@^0.6.1, source-map@~0.6.1:
   resolved "https://registry.yarnpkg.com/source-map/-/source-map-0.6.1.tgz#74722af32e9614e9c287a8d0bbde48b5e2f1a263"
   integrity sha512-UjgapumWlbMhkBgzT7Ykc5YXUT46F0iKu8SGXq0bcwP5dz/h0Plj6enJqjz1Zbq2l5WaqYnrVbwWOWMyF3F47g==
 
-source-map@^0.7.3:
+source-map@^0.7.3, source-map@~0.7.2:
   version "0.7.3"
   resolved "https://registry.yarnpkg.com/source-map/-/source-map-0.7.3.tgz#5302f8169031735226544092e64981f751750383"
   integrity sha512-CkCj6giN3S+n9qrYiBTX5gystlENnRW5jZeNLHpe6aue+SrHcG5VYwujhW9s4dY31mEGsxBDrHR6oI69fTXsaQ==
@@ -4195,14 +4195,14 @@ terminal-link@^2.0.0:
     ansi-escapes "^4.2.1"
     supports-hyperlinks "^2.0.0"
 
-terser@^3.10.11:
-  version "3.17.0"
-  resolved "https://registry.yarnpkg.com/terser/-/terser-3.17.0.tgz#f88ffbeda0deb5637f9d24b0da66f4e15ab10cb2"
-  integrity sha512-/FQzzPJmCpjAH9Xvk2paiWrFq+5M6aVOf+2KRbwhByISDX/EujxsK+BAvrhb6H+2rtrLCHK9N01wO014vrIwVQ==
+terser@^5.3.7:
+  version "5.3.7"
+  resolved "https://registry.yarnpkg.com/terser/-/terser-5.3.7.tgz#798a4ae2e7ff67050c3e99fcc4e00725827d97e2"
+  integrity sha512-lJbKdfxWvjpV330U4PBZStCT9h3N9A4zZVA5Y4k9sCWXknrpdyxi1oMsRKLmQ/YDMDxSBKIh88v0SkdhdqX06w==
   dependencies:
-    commander "^2.19.0"
-    source-map "~0.6.1"
-    source-map-support "~0.5.10"
+    commander "^2.20.0"
+    source-map "~0.7.2"
+    source-map-support "~0.5.19"
 
 test-exclude@^6.0.0:
   version "6.0.0"
@@ -4585,10 +4585,10 @@ word-wrap@^1.2.3, word-wrap@~1.2.3:
   resolved "https://registry.yarnpkg.com/word-wrap/-/word-wrap-1.2.3.tgz#610636f6b1f703891bd34771ccb17fb93b47079c"
   integrity sha512-Hz/mrNwitNRh/HUAtM/VT/5VH+ygD6DV7mYKZAtHOrbs8U7lvPS6xf7EJKMF0uW1KJCl0H701g3ZGus+muE5vQ==
 
-workerpool@^6.0.1:
-  version "6.0.1"
-  resolved "https://registry.yarnpkg.com/workerpool/-/workerpool-6.0.1.tgz#9e661102e074138125cb12197a7867547f2558d4"
-  integrity sha512-4I1YJngJuIAsJHOOJNPHQUjoA/Kr1QNtdRoPX8w92BtNy2pIo7zr6hQHDqm3d0CWnxmfcWsqxcFWN1Ni3w4C+g==
+workerpool@^6.0.2:
+  version "6.0.2"
+  resolved "https://registry.yarnpkg.com/workerpool/-/workerpool-6.0.2.tgz#e241b43d8d033f1beb52c7851069456039d1d438"
+  integrity sha512-DSNyvOpFKrNusaaUwk+ej6cBj1bmhLcBfj80elGk+ZIo5JSkq+unB1dLKEOcNfJDZgjGICfhQ0Q5TbP0PvF4+Q==
 
 wrap-ansi@^6.2.0:
   version "6.2.0"