diff --git a/Formula/wn.rb b/Formula/wn.rb
index c50fdaa..f16bd06 100644
--- a/Formula/wn.rb
+++ b/Formula/wn.rb
@@ -10,9 +10,14 @@ class Wn < Formula
 
   head "https://github.com/marmot-protocol/mdk.git", branch: "master"
 
+  depends_on "pkgconf" => :build
   depends_on "rust" => :build
+  depends_on "openssl@3"
 
   def install
+    # rusqlite pulls SQLCipher, whose openssl-sys build script locates the
+    # OpenSSL crypto lib via pkgconf. macOS build envs supply it implicitly;
+    # minimal Linux containers do not, so declare it explicitly for both.
     system "cargo", "install", *std_cargo_args(path: "crates/cli"), "--bins"
   end