diff --git a/fixtures/.yarnrc.yml b/fixtures/.yarnrc.yml
new file mode 100644
index 00000000..e797da6d
--- /dev/null
+++ b/fixtures/.yarnrc.yml
@@ -0,0 +1,6 @@
+#---
+# dependencies:
+#   zlib.net: ^1.2
+# env:
+#   FOO: BAR
+#---
diff --git a/src/utils/devenv.test.ts b/src/utils/devenv.test.ts
index 05e14098..0746d935 100644
--- a/src/utils/devenv.test.ts
+++ b/src/utils/devenv.test.ts
@@ -28,7 +28,8 @@ Deno.test("devenv.ts", async runner => {
         ["requirements.txt", "pip.pypa.io"],
         [".yarnrc", "classic.yarnpkg.com"],
         ["pixi.toml", "prefix.dev"],
-        ["action.yml/std/action.yml", "nodejs.org^16"]
+        ["action.yml/std/action.yml", "nodejs.org^16"],
+        [".yarnrc.yml", "yarnpkg.com"],
       ]
 
       for (const [keyfile, dep] of keyfiles) {
diff --git a/src/utils/devenv.ts b/src/utils/devenv.ts
index 7d7572db..d6a37f1e 100644
--- a/src/utils/devenv.ts
+++ b/src/utils/devenv.ts
@@ -70,6 +70,10 @@ export default async function(dir: Path) {
         pkgs.push({ project: "classic.yarnpkg.com", constraint })
         await read_YAML_FM(path)
         break
+      case ".yarnrc.yml":
+        pkgs.push({ project: "yarnpkg.com", constraint })
+        await read_YAML_FM(path)
+        break
       case "pixi.toml":
         pkgs.push({ project: 'prefix.dev', constraint })
         await read_YAML_FM(path)