diff --git a/pkgs/fablab/freeradius-anon-access/default.nix b/pkgs/fablab/freeradius-anon-access/default.nix
index c9e98bd..7b56597 100644
--- a/pkgs/fablab/freeradius-anon-access/default.nix
+++ b/pkgs/fablab/freeradius-anon-access/default.nix
@@ -1,4 +1,4 @@
-{ lib, stdenvNoCC, ... }:
+{ lib, freeradius, stdenvNoCC, ... }:
 
 stdenvNoCC.mkDerivation {
   name = "freeradius-anon-access";
@@ -7,7 +7,11 @@ stdenvNoCC.mkDerivation {
   installPhase = ''
     mkdir $out
     cp -r raddb $out
+    sed -i 's#@PREFIX@#${freeradius}#' $out/raddb/radiusd.conf
   '';
+  nativeBuildInputs = [
+    freeradius
+  ];
   meta = with lib; {
     platforms = platforms.unix;
   };
diff --git a/pkgs/fablab/freeradius-anon-access/raddb/radiusd.conf b/pkgs/fablab/freeradius-anon-access/raddb/radiusd.conf
index 9168b1e..965a495 100644
--- a/pkgs/fablab/freeradius-anon-access/raddb/radiusd.conf
+++ b/pkgs/fablab/freeradius-anon-access/raddb/radiusd.conf
@@ -80,11 +80,11 @@
 
 ######################################################################
 
-prefix = /nix/store/pciav5yyf7h5jyv4qqdi8k4yss5yxkxp-freeradius-3.0.25
+prefix = @PREFIX@
 exec_prefix = ${prefix}
 sysconfdir = /etc
 localstatedir = /var
-sbindir = /nix/store/pciav5yyf7h5jyv4qqdi8k4yss5yxkxp-freeradius-3.0.25/sbin
+sbindir = ${prefix}/sbin
 logdir = ${localstatedir}/log/radius
 raddbdir = ${sysconfdir}/raddb
 radacctdir = ${logdir}/radacct
@@ -135,7 +135,7 @@ db_dir = ${raddbdir}
 #	make
 #	make install
 #
-libdir = /nix/store/pciav5yyf7h5jyv4qqdi8k4yss5yxkxp-freeradius-3.0.25/lib
+libdir = ${prefix}/lib
 
 #  pidfile: Where to place the PID of the RADIUS server.
 #