diff --git a/CHANGELOG.md b/CHANGELOG.md
index db04dc1..902f8a7 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -6,6 +6,7 @@ Notable changes to this project are documented in this file. The format is based
 
 Breaking changes:
 - Update project and deps to PureScript v0.15.0 (#48 by @JordanMartinez)
+- Drop deprecated `MonadZero` instance (#49 by @JordanMartinez)
 
 New features:
 
diff --git a/package.json b/package.json
index 1dc06f2..c8e10e0 100644
--- a/package.json
+++ b/package.json
@@ -2,7 +2,7 @@
   "private": true,
   "scripts": {
     "clean": "rimraf output && rimraf .pulp-cache",
-    "build": "pulp build -- --censor-lib --strict --censor-codes='UserDefinedWarning'",
+    "build": "pulp build -- --censor-lib --strict",
     "test": "pulp test"
   },
   "devDependencies": {
diff --git a/src/Data/CatList.purs b/src/Data/CatList.purs
index d0d7aae..513850c 100644
--- a/src/Data/CatList.purs
+++ b/src/Data/CatList.purs
@@ -24,7 +24,6 @@ import Prelude hiding (append)
 import Control.Alt (class Alt)
 import Control.Alternative (class Alternative)
 import Control.MonadPlus (class MonadPlus)
-import Control.MonadZero (class MonadZero)
 import Control.Plus (class Plus)
 import Data.CatQueue as Q
 import Data.Foldable (class Foldable, foldMapDefaultL)
@@ -207,6 +206,4 @@ instance plusCatList :: Plus CatList where
 
 instance alternativeCatList :: Alternative CatList
 
-instance monadZeroCatList :: MonadZero CatList
-
 instance monadPlusCatList :: MonadPlus CatList
diff --git a/src/Data/CatQueue.purs b/src/Data/CatQueue.purs
index e4922cd..8e2143e 100644
--- a/src/Data/CatQueue.purs
+++ b/src/Data/CatQueue.purs
@@ -25,7 +25,6 @@ import Control.Alt (class Alt)
 import Control.Alternative (class Alternative)
 import Control.Apply (lift2)
 import Control.MonadPlus (class MonadPlus)
-import Control.MonadZero (class MonadZero)
 import Control.Plus (class Plus)
 import Data.Foldable (class Foldable, foldMap, foldMapDefaultL, foldl, foldrDefault)
 import Data.List (List(..), reverse)
@@ -191,6 +190,4 @@ instance plusCatQueue :: Plus CatQueue where
 
 instance alternativeCatQueue :: Alternative CatQueue
 
-instance monadZeroCatQueue :: MonadZero CatQueue
-
 instance monadPlusCatQueue :: MonadPlus CatQueue