diff --git a/pkgs/build-support/fetchurl/builder.sh b/pkgs/build-support/fetchurl/builder.sh
index b403ec245797..afbb90d43d07 100644
--- a/pkgs/build-support/fetchurl/builder.sh
+++ b/pkgs/build-support/fetchurl/builder.sh
@@ -4,10 +4,4 @@ header "downloading $out from $url"
 
 curl --fail --location --max-redirs 20 "$url" > "$out"
 
-actual=$(md5sum -b "$out" | cut -c1-32)
-if test "$actual" != "$md5"; then
-    echo "hash is $actual, expected $md5"
-    exit 1
-fi
-
 stopNest
diff --git a/pkgs/build-support/fetchurl/default.nix b/pkgs/build-support/fetchurl/default.nix
index b40b90985ac3..385a0a4c650c 100644
--- a/pkgs/build-support/fetchurl/default.nix
+++ b/pkgs/build-support/fetchurl/default.nix
@@ -1,11 +1,26 @@
-{stdenv, curl}: {url, md5}:
+# Argh, this thing is duplicated (more-or-less) in Nix (in corepkgs).
+# Need to find a way to combine them.
 
-# Note that `curl' may be `null', in case of the native stdenv.
+{stdenv, curl}: # Note that `curl' may be `null', in case of the native stdenv.
+
+{url, outputHash ? "", outputHashAlgo ? "", md5 ? "", sha1 ? "", sha256 ? ""}:
+
+assert (outputHash != "" && outputHashAlgo != "")
+    || md5 != "" || sha1 != "" || sha256 != "";
 
 stdenv.mkDerivation {
   name = baseNameOf (toString url);
   builder = ./builder.sh;
   buildInputs = [curl];
+
+  # Compatibility with Nix <= 0.7.
   id = md5;
-  inherit url md5;
+
+  # New-style output content requirements.
+  outputHashAlgo = if outputHashAlgo != "" then outputHashAlgo else
+      if sha256 != "" then "sha256" else if sha1 != "" then "sha1" else "md5";
+  outputHash = if outputHash != "" then outputHash else
+      if sha256 != "" then sha256 else if sha1 != "" then sha1 else md5;
+  
+  inherit url;
 }