diff --git a/Cargo.lock b/Cargo.lock
index dd8dd98..88a3068 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,5 +1,14 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
+[[package]]
+name = "ansi_term"
+version = "0.12.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d52a9bb7ec0cf484c551830a7ce27bd20d67eac647e1befb56b0be4ee39a55d2"
+dependencies = [
+ "winapi",
+]
+
 [[package]]
 name = "anyhow"
 version = "1.0.38"
@@ -38,6 +47,7 @@ dependencies = [
  "hex",
  "log",
  "nix 0.19.1",
+ "pretty_assertions",
  "proptest",
  "rand 0.8.3",
  "rayon",
@@ -195,6 +205,12 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "diff"
+version = "0.1.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0e25ea47919b1560c4e3b7fe0aaab9becf5b84a10325ddf7db0f0ba5e1026499"
+
 [[package]]
 name = "digest"
 version = "0.9.0"
@@ -420,12 +436,33 @@ version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "624a8340c38c1b80fd549087862da4ba43e08858af025b236e509b6649fc13d5"
 
+[[package]]
+name = "output_vt100"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "53cdc5b785b7a58c5aad8216b3dfa114df64b0b06ae6e1501cef91df2fbdf8f9"
+dependencies = [
+ "winapi",
+]
+
 [[package]]
 name = "ppv-lite86"
 version = "0.2.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ac74c624d6b2d21f425f752262f42188365d7b8ff1aff74c82e45136510a4857"
 
+[[package]]
+name = "pretty_assertions"
+version = "0.7.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1cab0e7c02cf376875e9335e0ba1da535775beb5450d21e1dffca068818ed98b"
+dependencies = [
+ "ansi_term",
+ "ctor",
+ "diff",
+ "output_vt100",
+]
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.24"
diff --git a/Cargo.toml b/Cargo.toml
index 4a32b2d..6f30472 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -34,6 +34,7 @@ walkdir = "2.3"
 [dev-dependencies]
 proptest = "0.10"
 two-rusty-forks = "0.4.0"
+pretty_assertions = "0.7"
 
 [dev-dependencies.cargo-husky]
 version = "1"
diff --git a/src/index/io.rs b/src/index/io.rs
index a264709..385b4ab 100644
--- a/src/index/io.rs
+++ b/src/index/io.rs
@@ -1,4 +1,3 @@
-use log::error;
 use std::collections::HashMap;
 use vfs::VfsPath;
 
@@ -132,7 +131,6 @@ mod must {
     use crate::index::Index;
     use anyhow::Result;
 
-    use rand::Rng;
     use vfs::{MemoryFS, VfsPath};
 
     #[test]
diff --git a/src/io/error_correcting_encoder.rs b/src/io/error_correcting_encoder.rs
index e5a4a93..52c7d15 100644
--- a/src/io/error_correcting_encoder.rs
+++ b/src/io/error_correcting_encoder.rs
@@ -14,6 +14,9 @@ pub fn encode(bytes: &[u8]) -> Result<Vec<u8>> {
 
 pub fn decode(bytes: &[u8]) -> Result<Vec<u8>> {
     let decoder = Decoder::new(ECC_LENGTH);
+    if decoder.is_corrupted(bytes) {
+        return Err(anyhow!("corrupted"));
+    }
     let maybe_corrected = decoder.correct(bytes, None);
     match maybe_corrected {
         Ok(corrected) => Ok(corrected.data().to_vec()),
@@ -21,6 +24,7 @@ pub fn decode(bytes: &[u8]) -> Result<Vec<u8>> {
     }
 }
 
+#[cfg(test)]
 mod must {
 
     use anyhow::Result;
@@ -28,6 +32,8 @@ mod must {
 
     use super::{decode, encode};
 
+    use pretty_assertions::assert_eq;
+
     #[test]
     fn survive_data_corruption() -> Result<()> {
         let mut original: [u8; 32] = [0; 32];
@@ -35,14 +41,13 @@ mod must {
 
         let encoded = encode(&original)?;
 
-        let size = dbg!(encoded.len());
+        let size = encoded.len();
         let corrupt_byte_index = rand::thread_rng().gen_range::<usize, _>(0..size);
 
-        let mut corrupted: [u8; 32] = [0; 32];
-        corrupted.copy_from_slice(&encoded);
+        let mut corrupted = Vec::from(encoded);
         corrupted[corrupt_byte_index] = rand::thread_rng().gen::<u8>();
 
-        let decoded = decode(&corrupted)?;
+        let decoded = decode(&corrupted).unwrap();
 
         assert_eq!(decoded, original);