diff --git a/src/nix-env/Makefile.am b/src/nix-env/Makefile.am
index 900524f76e..9b0d995136 100644
--- a/src/nix-env/Makefile.am
+++ b/src/nix-env/Makefile.am
@@ -1,6 +1,7 @@
 bin_PROGRAMS = nix-env
 
-nix_env_SOURCES = nix-env.cc profiles.cc profiles.hh help.txt
+nix_env_SOURCES = nix-env.cc profiles.cc user-env.cc profiles.hh help.txt
+
 nix_env_LDADD = ../libmain/libmain.la ../libexpr/libexpr.la \
  ../libstore/libstore.la ../libutil/libutil.la \
  ../boost/format/libformat.la ${aterm_lib} @ADDITIONAL_NETWORK_LIBS@
diff --git a/src/nix-env/nix-env.cc b/src/nix-env/nix-env.cc
index 306b9507d1..e298c4003b 100644
--- a/src/nix-env/nix-env.cc
+++ b/src/nix-env/nix-env.cc
@@ -12,6 +12,7 @@
 #include "common-opts.hh"
 #include "xml-writer.hh"
 #include "store-api.hh"
+#include "user-env.hh"
 #include "util.hh"
 
 #include <cerrno>
@@ -192,25 +193,6 @@ static Path getDefNixExprPath()
 }
 
 
-static DrvInfos queryInstalled(EvalState & state, const Path & userEnv)
-{
-    Path path = userEnv + "/manifest";
-
-    if (!pathExists(path))
-        return DrvInfos(); /* not an error, assume nothing installed */
-
-    throw Error("not implemented");
-#if 0
-    Expr e = ATreadFromNamedFile(path.c_str());
-    if (!e) throw Error(format("cannot read Nix expression from `%1%'") % path);
-
-    DrvInfos elems;
-    // !!! getDerivations(state, e, "", ATermMap(1), elems);
-    return elems;
-#endif
-}
-
-
 /* Ensure exclusive access to a profile.  Any command that modifies
    the profile first acquires this lock. */
 static void lockProfile(PathLocks & lock, const Path & profile)
diff --git a/src/nix-env/user-env.cc b/src/nix-env/user-env.cc
new file mode 100644
index 0000000000..0e1fce650c
--- /dev/null
+++ b/src/nix-env/user-env.cc
@@ -0,0 +1,28 @@
+#include "util.hh"
+#include "get-drvs.hh"
+
+
+namespace nix {
+
+
+DrvInfos queryInstalled(EvalState & state, const Path & userEnv)
+{
+    Path path = userEnv + "/manifest";
+
+    if (!pathExists(path))
+        return DrvInfos(); /* not an error, assume nothing installed */
+
+    throw Error("not implemented");
+#if 0
+    Expr e = ATreadFromNamedFile(path.c_str());
+    if (!e) throw Error(format("cannot read Nix expression from `%1%'") % path);
+
+    DrvInfos elems;
+    // !!! getDerivations(state, e, "", ATermMap(1), elems);
+    return elems;
+#endif
+}
+
+
+}
+
diff --git a/src/nix-env/user-env.hh b/src/nix-env/user-env.hh
new file mode 100644
index 0000000000..6675014f1a
--- /dev/null
+++ b/src/nix-env/user-env.hh
@@ -0,0 +1,16 @@
+#ifndef __USER_ENV_H
+#define __USER_ENV_H
+
+#include "get-drvs.hh"
+
+namespace nix {
+
+DrvInfos queryInstalled(EvalState & state, const Path & userEnv);
+
+}
+
+#endif /* !__USER_ENV_H */
+
+
+
+