diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,7 @@
+1.0.18
+
+* [Document the `--color` command-line option](https://github.com/Gabriel439/nix-diff/pull/54)
+
 1.0.17
 
 * [Handle `.drv` and `.nix` files that contain non-UTF8 text](https://github.com/Gabriel439/nix-diff/pull/50)
diff --git a/nix-diff.cabal b/nix-diff.cabal
--- a/nix-diff.cabal
+++ b/nix-diff.cabal
@@ -1,5 +1,5 @@
 name:                nix-diff
-version:             1.0.17
+version:             1.0.18
 synopsis:            Explain why two Nix derivations differ
 description:         This package provides a @nix-diff@ executable which
                      explains why two Nix derivations (i.e. @*.drv@ files)
@@ -20,7 +20,7 @@
 executable nix-diff
   main-is:             Main.hs
   build-depends:       base                 >= 4.9      && < 5
-                     , attoparsec           >= 0.13     && < 0.14
+                     , attoparsec           >= 0.13     && < 0.15
                      , bytestring           >= 0.9      && < 0.12
                      , containers           >= 0.5      && < 0.7
                      , directory                           < 1.4
diff --git a/src/Main.hs b/src/Main.hs
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -61,6 +61,7 @@
     Options.Applicative.option
         reader
         (   Options.Applicative.long "color"
+        <>  Options.Applicative.help ("display colors always, automatically (if terminal detected), or never")
         <>  Options.Applicative.value Auto
         <>  Options.Applicative.metavar "(always|auto|never)"
         )