diff --git a/appveyor.yml b/appveyor.yml
index 3981e91b4..eb2119a23 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -39,13 +39,18 @@ for:
     # install modules
     - ps: >-
         if ($env:nodejs_version -eq "4") {
-          npm install -g npm@3;
+          cmd /c npm install -g npm@3;
         }
         if ($env:nodejs_version -in @("8", "10", "12")) {
-          npm install -g npm@6.10.3;
+          cmd /c npm install -g npm@6.14.5;
         }
     - npm install
 
+    - ps: >-
+        if ([int]$env:nodejs_version -le 8) {
+          cmd /c npm i eslint@6 2`>`&1;
+        }
+
     # fix symlinks
     - git config core.symlinks true
     - git reset --hard
@@ -54,6 +59,20 @@ for:
     - cd .\resolvers\webpack && npm install && cd ..\..
     - cd .\resolvers\node && npm install && cd ..\..
 
+    # Upgrade nyc
+    - npm i --no-save nyc@15.0.1
+    - ps: >-
+        $resolverDir = "./resolvers";
+        Get-ChildItem -Directory $resolverDir |
+        ForEach-Object {
+          Push-Location $(Resolve-Path $(Join-Path $resolverDir $_));
+          cmd /c npm ls nyc 2`>`&1;
+          if ($?) {
+            cmd /c npm i --no-save nyc@15.0.1 2`>`&1;
+          }
+          Pop-Location;
+        }
+
   # Post-install test scripts.
   test_script:
 
diff --git a/package.json b/package.json
index 4191d11d2..0673205f3 100644
--- a/package.json
+++ b/package.json
@@ -31,7 +31,7 @@
     "test-compiled": "npm run prepublish && BABEL_ENV=testCompiled mocha --compilers js:babel-register tests/src",
     "test-all": "node --require babel-register ./scripts/testAll",
     "prepublish": "not-in-publish || npm run build",
-    "coveralls": "nyc report --reporter lcovonly && cat ./coverage/lcov.info | coveralls"
+    "coveralls": "nyc report --reporter lcovonly && coveralls < ./coverage/lcov.info"
   },
   "repository": {
     "type": "git",