diff --git a/.justfile b/.justfile
index 6c6176c..a1123dd 100644
--- a/.justfile
+++ b/.justfile
@@ -46,10 +46,10 @@ justFmt:
     just --unstable --fmt
 
 mdFmtCheck:
-    git ls-files | grep -E '^.*\.(md|MD)$' | xargs deno fmt --check --ext md
+    git ls-files | grep -E '^.*\.md$' | xargs deno fmt --check --ext md
 
 mdFmt:
-    git ls-files | grep -E '^.*\.(md|MD)$' | xargs deno fmt --ext md
+    git ls-files | grep -E '^.*\.md$' | xargs deno fmt --ext md
 
 ymlFmtCheck:
     git ls-files | grep -E '^.*\.yml$' | xargs deno fmt --check --ext yml
diff --git a/Cargo.toml b/Cargo.toml
index 74f1052..df5865b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -6,6 +6,7 @@ members = ["mania", "mania-macros", "mania-codec", "examples"]
 version = "0.0.1"
 edition = "2024"
 license-file = "LICENCE"
+readme = "README.md"
 
 [workspace.dependencies]
 md-5 = "0.11.0-pre.4"
diff --git a/README.MD b/README.md
similarity index 100%
rename from README.MD
rename to README.md
diff --git a/flake.nix b/flake.nix
index 25b6547..6bd6bed 100644
--- a/flake.nix
+++ b/flake.nix
@@ -44,7 +44,7 @@
               ".github"
               ".gitignore"
               "rust-toolchain.toml"
-              "README.MD"
+              "README.md"
               "flake.nix"
               "flake.lock"
               "target"
@@ -140,7 +140,7 @@
                   just --unstable --fmt --check
                   # markdown
                   echo '==> markdown format check'
-                  find . -type f -regextype egrep -regex '^.*\.(md|MD)$' -exec deno fmt --check --ext md {} +
+                  find . -type f -regextype egrep -regex '^.*\.md$' -exec deno fmt --check --ext md {} +
                   # toml
                   echo '==> toml format check'
                   find . -type f -regextype egrep -regex '^.*\.toml$' -exec taplo format --check {} +
diff --git a/mania-codec/Cargo.toml b/mania-codec/Cargo.toml
index 6f68e9d..ec85717 100644
--- a/mania-codec/Cargo.toml
+++ b/mania-codec/Cargo.toml
@@ -3,6 +3,7 @@ name = "mania-codec"
 version.workspace = true
 edition.workspace = true
 license-file.workspace = true
+readme = "README.md"
 
 [dependencies]
 num-traits = "0.2.19"
diff --git a/mania-codec/README.MD b/mania-codec/README.md
similarity index 100%
rename from mania-codec/README.MD
rename to mania-codec/README.md
diff --git a/mania/src/core/protos/README.MD b/mania/src/core/protos/README.md
similarity index 100%
rename from mania/src/core/protos/README.MD
rename to mania/src/core/protos/README.md