diff --git a/lighthouse-cli/test/smokehouse/frontends/lib.js b/lighthouse-cli/test/smokehouse/frontends/lib.js
index b1f53be7ee97..c48800b8ab68 100644
--- a/lighthouse-cli/test/smokehouse/frontends/lib.js
+++ b/lighthouse-cli/test/smokehouse/frontends/lib.js
@@ -13,6 +13,7 @@
 
 /* eslint-disable no-console */
 
+const cloneDeep = require('lodash.clonedeep');
 const smokeTests = require('../test-definitions/core-tests.js');
 const {runSmokehouse} = require('../smokehouse.js');
 
@@ -22,8 +23,7 @@ const {runSmokehouse} = require('../smokehouse.js');
 async function smokehouse(options) {
   const {urlFilterRegex, skip, modify, ...smokehouseOptions} = options;
 
-  /** @type {Smokehouse.TestDfn[]} */
-  const clonedTests = JSON.parse(JSON.stringify(smokeTests));
+  const clonedTests = cloneDeep(smokeTests);
   const modifiedTests = clonedTests.map(test => {
     const modifiedExpectations = [];
     for (const expected of test.expectations) {
diff --git a/lighthouse-cli/test/smokehouse/smokehouse.js b/lighthouse-cli/test/smokehouse/smokehouse.js
index 3ff26a068e6f..e5f9249b2c2d 100644
--- a/lighthouse-cli/test/smokehouse/smokehouse.js
+++ b/lighthouse-cli/test/smokehouse/smokehouse.js
@@ -144,7 +144,7 @@ async function runSmokeTestDefn(concurrentMapper, smokeTestDefn, defnOptions) {
       passingTestCount++;
     }
 
-    process.stdout.write(result.log);
+    console.log(result.log);
   }
 
   console.log(`${purpleify(id)} smoketest complete.`);
diff --git a/package.json b/package.json
index d0768e65bb3d..a60baa6829cf 100644
--- a/package.json
+++ b/package.json
@@ -90,6 +90,7 @@
     "@types/inquirer": "^0.0.35",
     "@types/jest": "^24.0.9",
     "@types/jpeg-js": "^0.3.0",
+    "@types/lodash.clonedeep": "^4.5.6",
     "@types/lodash.isequal": "^4.5.2",
     "@types/lodash.set": "^4.3.6",
     "@types/node": "*",
@@ -128,6 +129,7 @@
     "jest": "^24.9.0",
     "jsdom": "^12.2.0",
     "lighthouse-plugin-publisher-ads": "^0.4.1",
+    "lodash.clonedeep": "^4.5.0",
     "npm-run-posix-or-windows": "^2.0.2",
     "nyc": "^13.3.0",
     "package-json-versionify": "^1.0.4",
diff --git a/yarn.lock b/yarn.lock
index ae614a6e8542..83beddef06e3 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -569,6 +569,13 @@
   resolved "https://registry.yarnpkg.com/@types/json-schema/-/json-schema-7.0.3.tgz#bdfd69d61e464dcc81b25159c270d75a73c1a636"
   integrity sha512-Il2DtDVRGDcqjDtE+rF8iqg1CArehSK84HZJCT7AMITlyXRBpuPhqGLDQMowraqqu1coEaimg4ZOqggt6L6L+A==
 
+"@types/lodash.clonedeep@^4.5.6":
+  version "4.5.6"
+  resolved "https://registry.yarnpkg.com/@types/lodash.clonedeep/-/lodash.clonedeep-4.5.6.tgz#3b6c40a0affe0799a2ce823b440a6cf33571d32b"
+  integrity sha512-cE1jYr2dEg1wBImvXlNtp0xDoS79rfEdGozQVgliDZj1uERH4k+rmEMTudP9b4VQ8O6nRb5gPqft0QzEQGMQgA==
+  dependencies:
+    "@types/lodash" "*"
+
 "@types/lodash.isequal@^4.5.2":
   version "4.5.2"
   resolved "https://registry.yarnpkg.com/@types/lodash.isequal/-/lodash.isequal-4.5.2.tgz#adbdff67f7c956ed703009e5466a34eeddb0b712"
@@ -5231,6 +5238,11 @@ lodash.assign@^4.2.0:
   resolved "https://registry.yarnpkg.com/lodash.assign/-/lodash.assign-4.2.0.tgz#0d99f3ccd7a6d261d19bdaeb9245005d285808e7"
   integrity sha1-DZnzzNem0mHRm9rrkkUAXShYCOc=
 
+lodash.clonedeep@^4.5.0:
+  version "4.5.0"
+  resolved "https://registry.yarnpkg.com/lodash.clonedeep/-/lodash.clonedeep-4.5.0.tgz#e23f3f9c4f8fbdde872529c1071857a086e5ccef"
+  integrity sha1-4j8/nE+Pvd6HJSnBBxhXoIblzO8=
+
 lodash.defaults@^4.2.0:
   version "4.2.0"
   resolved "https://registry.yarnpkg.com/lodash.defaults/-/lodash.defaults-4.2.0.tgz#d09178716ffea4dde9e5fb7b37f6f0802274580c"