diff --git a/package-lock.json b/package-lock.json
index 45c742a..599bef1 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -687,32 +687,42 @@
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@@ -7572,6 +7547,23 @@
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@@ -8336,39 +8328,39 @@
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-        "lolex": "^3.1.0",
-        "nise": "^1.4.10",
-        "supports-color": "^5.5.0"
+        "@sinonjs/commons": "^1.7.0",
+        "@sinonjs/fake-timers": "^6.0.0",
+        "@sinonjs/formatio": "^5.0.1",
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diff --git a/package.json b/package.json
index 62f94a7..b6152bf 100644
--- a/package.json
+++ b/package.json
@@ -33,7 +33,7 @@
     "mocha": "^4.1.0",
     "nyc": "^13.3.0",
     "prettier": "^1.10.2",
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+    "sinon": "^9.0.1"
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   "dependencies": {
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