diff --git a/src/backend/Makefile.am b/src/backend/Makefile.am
index da39e71c6..be9b9cd90 100644
--- a/src/backend/Makefile.am
+++ b/src/backend/Makefile.am
@@ -29,6 +29,7 @@ liblumibackend_a_SOURCES =					\
 	$(liblumibackend_a_srcdir)/filehandlecache.c		\
 	$(liblumibackend_a_srcdir)/interface.c			\
 	$(liblumibackend_a_srcdir)/interfaceregistry.c		\
+	$(liblumibackend_a_srcdir)/plugin.c			\
 	$(liblumibackend_a_srcdir)/config.c			\
 	$(liblumibackend_a_srcdir)/config_typed.c 		\
 	$(liblumibackend_a_srcdir)/config_wordlist.c 		\
@@ -47,6 +48,7 @@ noinst_HEADERS +=						\
 	$(liblumibackend_a_srcdir)/interface.h			\
 	$(liblumibackend_a_srcdir)/interfaceregistry.h		\
 	$(liblumibackend_a_srcdir)/interfacedescriptor.h	\
+	$(liblumibackend_a_srcdir)/plugin.h			\
 	$(liblumibackend_a_srcdir)/config.h 			\
 	$(liblumibackend_a_srcdir)/configentry.h 		\
 	$(liblumibackend_a_srcdir)/configitem.h 		\
diff --git a/src/backend/config.h b/src/backend/config.h
index 4e3acd9a9..445ed6e23 100644
--- a/src/backend/config.h
+++ b/src/backend/config.h
@@ -228,20 +228,22 @@ LUMIERA_CONFIG_TYPES
  * Get nth word of a wordlist.
  * @param key key under which this wordlist is stored
  * @param nth index of the word to get, starting with 0
+ * @param delims a string literal listing all characters which are treated as delimiters
  * @return pointer to a tempbuf holding the nth word or NULL in case of error
  */
 const char*
-lumiera_config_wordlist_get_nth (const char* key, unsigned nth);
+lumiera_config_wordlist_get_nth (const char* key, unsigned nth, const char* delims);
 
 
 /**
  * Find the index of a word in a wordlist.
  * @param key key under which this wordlist is stored
  * @param value word to find
+ * @param delims a string literal listing all characters which are treated as delimiters
  * @return index of the first occurence of the word or -1 in case of failure
  */
 int
-lumiera_config_wordlist_find (const char* key, const char* value);
+lumiera_config_wordlist_find (const char* key, const char* value, const char* delims);
 
 
 /**
@@ -254,20 +256,22 @@ lumiera_config_wordlist_find (const char* key, const char* value);
  * @param value word to be replaced
  * @param subst1 first replacement word
  * @param subst2 second replacement word
+ * @param delims a string literal listing all characters which are treated as delimiters
  * @return internal representation of the wordlist in a tmpbuf or NULL in case of an error
  */
 const char*
-lumiera_config_wordlist_replace (const char* key, const char* value, const char* subst1, const char* subst2);
+lumiera_config_wordlist_replace (const char* key, const char* value, const char* subst1, const char* subst2, const char* delims);
 
 
 /**
  * Add a word to the end of a wordlist if it doesnt exist already
  * @param key key under which this wordlist is stored
  * @param value new word to add
+ * @param delims a string literal listing all characters which are treated as delimiters
  * @return internal representation of the wordlist in a tmpbuf or NULL in case of an error
  */
 const char*
-lumiera_config_wordlist_add (const char* key, const char* value);
+lumiera_config_wordlist_add (const char* key, const char* value, const char* delims);
 
 //  * {{{ lumiera_config_TYPE_set (const char* key, TYPE*value, const char* fmt) }}}
 //    Highlevel interface for different types, fmt is a printf format specifier for the desired format, when NULL, defaults apply.
diff --git a/src/backend/config_wordlist.c b/src/backend/config_wordlist.c
index 6cd0389a7..47232f483 100644
--- a/src/backend/config_wordlist.c
+++ b/src/backend/config_wordlist.c
@@ -19,25 +19,20 @@
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
 
-//TODO: Support library includes//
 #include "lib/error.h"
 #include "lib/safeclib.h"
 
 
-//TODO: Lumiera header includes//
 #include "backend/config.h"
 
-//TODO: internal/static forward declarations//
 extern LumieraConfig lumiera_global_config;
 
 
-//TODO: System includes//
-
 /**
  * return nth word of a wordlist
  */
 const char*
-lumiera_config_wordlist_get_nth (const char* key, unsigned nth)
+lumiera_config_wordlist_get_nth (const char* key, unsigned nth, const char* delims)
 {
   const char* value;
   size_t len;
@@ -47,8 +42,8 @@ lumiera_config_wordlist_get_nth (const char* key, unsigned nth)
 
   for (;;)
     {
-      value += strspn (value, " \t,;");
-      len = strcspn (value, " \t,;");
+      value += strspn (value, delims);
+      len = strcspn (value, delims);
       if (!nth && *value)
         break;
 
@@ -64,7 +59,7 @@ lumiera_config_wordlist_get_nth (const char* key, unsigned nth)
 
 
 int
-lumiera_config_wordlist_find (const char* key, const char* value)
+lumiera_config_wordlist_find (const char* key, const char* value, const char* delims)
 {
   const char* itr;
   size_t vlen = strlen (value);
@@ -75,8 +70,8 @@ lumiera_config_wordlist_find (const char* key, const char* value)
 
   for (int idx = 0; *itr; itr += len, ++idx)
     {
-      itr += strspn (itr, " \t,;");
-      len = strcspn (itr, " \t,;");
+      itr += strspn (itr, delims);
+      len = strcspn (itr, delims);
 
       if (len == vlen && !strncmp (itr, value, vlen))
         return idx;
@@ -87,7 +82,7 @@ lumiera_config_wordlist_find (const char* key, const char* value)
 
 
 const char*
-lumiera_config_wordlist_replace (const char* key, const char* value, const char* subst1, const char* subst2)
+lumiera_config_wordlist_replace (const char* key, const char* value, const char* subst1, const char* subst2, const char* delims)
 {
   const char* wordlist;
   const char* str = NULL;
@@ -106,28 +101,25 @@ lumiera_config_wordlist_replace (const char* key, const char* value, const char*
           for (const char* itr = start; *itr; itr += len)
             {
               const char* left_end = itr;
-              itr += strspn (itr, " \t,;");
-              len = strcspn (itr, " \t,;");
+              itr += strspn (itr, delims);
+              len = strcspn (itr, delims);
 
               if (len == vlen && !strncmp (itr, value, vlen))
                 {
-                  TODO ("figure delimiter from original string out");
-                  const char* delim = " ";
-
                   /* step over the word */
                   itr += len;
-                  itr += strspn (itr, " \t,;");
+                  itr += strspn (itr, delims);
 
                   /* getting the delimiters right for the corner cases looks ugly, want to refactor it? just do it */
                   str = lumiera_tmpbuf_snprintf (SIZE_MAX,
-                                                 "%.*s%.*s%s%s%s%s%s%s",
+                                                 "%.*s%.*s%.1s%s%.1s%s%.1s%s",
                                                  start - wordlist, wordlist,
                                                  left_end - start, start,
-                                                 (left_end - start && subst1 && *subst1) ? delim : "",
+                                                 (left_end - start && subst1 && *subst1) ? delims : "",
                                                  (subst1 && *subst1) ? subst1 : "",
-                                                 ((left_end - start || (subst1 && *subst1)) && subst2 && *subst2) ? delim : "",
+                                                 ((left_end - start || (subst1 && *subst1)) && subst2 && *subst2) ? delims : "",
                                                  (subst2 && *subst2) ? subst2 : "",
-                                                 ((left_end - start || (subst1 && *subst1) || (subst2 && *subst2)) && *itr) ? delim : "",
+                                                 ((left_end - start || (subst1 && *subst1) || (subst2 && *subst2)) && *itr) ? delims : "",
                                                  itr
                                                  );
 
@@ -145,7 +137,7 @@ lumiera_config_wordlist_replace (const char* key, const char* value, const char*
 
 
 const char*
-lumiera_config_wordlist_add (const char* key, const char* value)
+lumiera_config_wordlist_add (const char* key, const char* value, const char* delims)
 {
   const char* wordlist = NULL;
 
@@ -160,19 +152,16 @@ lumiera_config_wordlist_add (const char* key, const char* value)
 
               for (const char* itr = wordlist; *itr; itr += len)
                 {
-                  itr += strspn (itr, " \t,;");
-                  len = strcspn (itr, " \t,;");
+                  itr += strspn (itr, delims);
+                  len = strcspn (itr, delims);
 
                   if (len == vlen && !strncmp (itr, value, vlen))
                     goto end;
                 }
 
-              TODO ("figure delimiter from original string out");
-              const char* delim = " ";
-
-              wordlist = lumiera_tmpbuf_snprintf (SIZE_MAX, "%s%s%s",
+              wordlist = lumiera_tmpbuf_snprintf (SIZE_MAX, "%s%.1s%s",
                                                   wordlist,
-                                                  wordlist[strspn (wordlist, " \t,;")]?delim:"",
+                                                  wordlist[strspn (wordlist, delims)] ? delims : "",
                                                   value);
 
               if (!lumiera_config_set (key, lumiera_tmpbuf_snprintf (SIZE_MAX, "=%s", wordlist)))
diff --git a/src/backend/interfaceregistry.c b/src/backend/interfaceregistry.c
index ffa979340..05e2224a1 100644
--- a/src/backend/interfaceregistry.c
+++ b/src/backend/interfaceregistry.c
@@ -29,6 +29,7 @@
 
 
 
+#include "backend/plugin.h"
 #include "backend/interfaceregistry.h"
 
 /**
@@ -39,27 +40,32 @@
  */
 
 NOBUG_DEFINE_FLAG_PARENT (interface_all, backend);
+NOBUG_DEFINE_FLAG_PARENT (plugin, interface_all);
 NOBUG_DEFINE_FLAG_PARENT (interfaceregistry, interface_all);
 NOBUG_DEFINE_FLAG_PARENT (interface, interface_all);
 
 PSplay lumiera_interfaceregistry;
+PSplay lumiera_pluginregistry;
 lumiera_mutex lumiera_interface_mutex;
 
 static int
-cmp_fn (const void* keya, const void* keyb);
+lumiera_interface_cmp_fn (const void* keya, const void* keyb);
 
 static const void*
-key_fn (const PSplaynode node);
+lumiera_interface_key_fn (const PSplaynode node);
+
 
 
 static LumieraInterfacenode
-lumiera_interfacenode_new (LumieraInterface iface)
+lumiera_interfacenode_new (LumieraInterface iface, LumieraPlugin plugin)
 {
   LumieraInterfacenode self = lumiera_malloc (sizeof (*self));
 
   psplaynode_init (&self->node);
   self->interface = iface;
   self->refcnt = 0;
+  self->plugin = plugin;
+  FIXME ("plugin handling (refcnt, atime)");
   self->lnk = NULL;
   self->deps_size = 0;
   self->deps = NULL;
@@ -74,6 +80,7 @@ lumiera_interfacenode_delete (LumieraInterfacenode self)
   if (self)
     {
       REQUIRE (self->refcnt == 0);
+      FIXME ("plugin handling");
       lumiera_free (self->deps);
       lumiera_free (self);
     }
@@ -89,13 +96,20 @@ lumiera_interfaceregistry_init (void)
   NOBUG_INIT_FLAG (interface_all);
   NOBUG_INIT_FLAG (interfaceregistry);
   NOBUG_INIT_FLAG (interface);
+  NOBUG_INIT_FLAG (plugin);
+
   TRACE (interfaceregistry);
   REQUIRE (!lumiera_interfaceregistry);
+  REQUIRE (!lumiera_pluginregistry);
 
-  lumiera_interfaceregistry = psplay_new (cmp_fn, key_fn, NULL);
+  lumiera_interfaceregistry = psplay_new (lumiera_interface_cmp_fn, lumiera_interface_key_fn, NULL);
   if (!lumiera_interfaceregistry)
     LUMIERA_DIE (ERRNO);
 
+  lumiera_pluginregistry = psplay_new (lumiera_plugin_cmp_fn, lumiera_plugin_key_fn, NULL);
+  if (!lumiera_pluginregistry)
+    LUMIERA_DIE (ERRNO);
+
   lumiera_recmutex_init (&lumiera_interface_mutex, "interfaceregistry", &NOBUG_FLAG(interfaceregistry));
 }
 
@@ -111,11 +125,18 @@ lumiera_interfaceregistry_destroy (void)
   if (lumiera_interfaceregistry)
     psplay_destroy (lumiera_interfaceregistry);
   lumiera_interfaceregistry = NULL;
+
+  TODO ("provide a delete function for the psplay tree to tear it down");
+  REQUIRE (psplay_nelements (lumiera_pluginregistry) == 0, "plugins still loaded at destroy");
+
+  if (lumiera_pluginregistry)
+    psplay_delete (lumiera_pluginregistry);
+  lumiera_pluginregistry = NULL;
 }
 
 
 void
-lumiera_interfaceregistry_register_interface (LumieraInterface self)
+lumiera_interfaceregistry_register_interface (LumieraInterface self, LumieraPlugin plugin)
 {
   TRACE (interfaceregistry);
   REQUIRE (self);
@@ -123,13 +144,13 @@ lumiera_interfaceregistry_register_interface (LumieraInterface self)
   LUMIERA_RECMUTEX_SECTION (interfaceregistry, &lumiera_interface_mutex)
     {
       TRACE (interfaceregistry, "interface %s, version %d, instance %s", self->interface, self->version, self->name);
-      psplay_insert (lumiera_interfaceregistry, &lumiera_interfacenode_new (self)->node, 100);
+      psplay_insert (lumiera_interfaceregistry, &lumiera_interfacenode_new (self, plugin)->node, 100);
     }
 }
 
 
 void
-lumiera_interfaceregistry_bulkregister_interfaces (LumieraInterface* self)
+lumiera_interfaceregistry_bulkregister_interfaces (LumieraInterface* self, LumieraPlugin plugin)
 {
   TRACE (interfaceregistry);
   REQUIRE (self);
@@ -139,7 +160,7 @@ lumiera_interfaceregistry_bulkregister_interfaces (LumieraInterface* self)
       while (*self)
         {
           TRACE (interfaceregistry, "interface %s, version %d, instance %s", (*self)->interface, (*self)->version, (*self)->name);
-          psplay_insert (lumiera_interfaceregistry, &lumiera_interfacenode_new (*self)->node, 100);
+          psplay_insert (lumiera_interfaceregistry, &lumiera_interfacenode_new (*self, plugin)->node, 100);
           ++self;
         }
     }
@@ -213,7 +234,7 @@ lumiera_interfaceregistry_interface_find (const char* interface, unsigned versio
 
 
 static int
-cmp_fn (const void* keya, const void* keyb)
+lumiera_interface_cmp_fn (const void* keya, const void* keyb)
 {
   const LumieraInterface a = (const LumieraInterface)keya;
   const LumieraInterface b = (const LumieraInterface)keyb;
@@ -240,12 +261,11 @@ cmp_fn (const void* keya, const void* keyb)
 
 
 static const void*
-key_fn (const PSplaynode node)
+lumiera_interface_key_fn (const PSplaynode node)
 {
   return ((LumieraInterfacenode)node)->interface;
 }
 
-
 /*
 // Local Variables:
 // mode: C
diff --git a/src/backend/interfaceregistry.h b/src/backend/interfaceregistry.h
index 02481072d..54ede293a 100644
--- a/src/backend/interfaceregistry.h
+++ b/src/backend/interfaceregistry.h
@@ -25,6 +25,7 @@
 #include "lib/psplay.h"
 
 #include "backend/interface.h"
+#include "backend/plugin.h"
 
 #include <nobug.h>
 
@@ -62,6 +63,10 @@ struct lumiera_interfacenode_struct
 
   /** reference counters and link used for internal reference management */
   unsigned refcnt;
+
+  /** backreference to its plugin if it comes from a plugin, else NULL */
+  LumieraPlugin plugin;
+
   /** temporary used to stack interfaces when recursively opening/closing them */
   LumieraInterfacenode lnk;
   /** allocated size of the following deps table */
@@ -84,10 +89,10 @@ lumiera_interfaceregistry_destroy (void);
 
 
 void
-lumiera_interfaceregistry_register_interface (LumieraInterface self);
+lumiera_interfaceregistry_register_interface (LumieraInterface self, LumieraPlugin plugin);
 
 void
-lumiera_interfaceregistry_bulkregister_interfaces (LumieraInterface* self);
+lumiera_interfaceregistry_bulkregister_interfaces (LumieraInterface* self, LumieraPlugin plugin);
 
 void
 lumiera_interfaceregistry_remove_interface (LumieraInterface self);
diff --git a/src/backend/plugin.c b/src/backend/plugin.c
index f6ecd7649..1b708c6be 100644
--- a/src/backend/plugin.c
+++ b/src/backend/plugin.c
@@ -18,72 +18,72 @@
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
-#include <stdio.h>
-#include <unistd.h>
-#include <search.h>
-#include <string.h>
-#include <dlfcn.h>
-#include <pthread.h>
-#include <time.h>
-#include <limits.h>
-
 #include "lib/safeclib.h"
+#include "lib/psplay.h"
+#include "lib/mutex.h"
+#include "lib/error.h"
 
+#include "backend/interfaceregistry.h"
+#include "backend/config.h"
 #include "backend/plugin.h"
 
+#include <glob.h>
+
+#include <nobug.h>
+
 /**
  * @file
  * Plugin loader.
  */
 
+extern PSplay lumiera_pluginregistry;
 
 /* TODO should be set by the build system to the actual plugin path */
-#define LUMIERA_PLUGIN_PATH "~/.lumiera/plugins:/usr/local/lib/lumiera/plugins:.libs"
-
-NOBUG_DEFINE_FLAG (lumiera_plugin);
 
 /* errors */
 LUMIERA_ERROR_DEFINE(PLUGIN_DLOPEN, "Could not open plugin");
-LUMIERA_ERROR_DEFINE(PLUGIN_HOOK, "Hook function failed");
-LUMIERA_ERROR_DEFINE(PLUGIN_NFILE, "No such plugin");
-LUMIERA_ERROR_DEFINE(PLUGIN_NIFACE, "No such interface");
-LUMIERA_ERROR_DEFINE(PLUGIN_REVISION, "Interface revision too old");
 
 /*
   supported (planned) plugin types and their file extensions
 */
 
+#define LUMIERA_PLUGIN_TYPES            \
+  LUMIERA_PLUGIN_TYPE(DYNLIB, ".so")
+
+/*
+  only .so dynlibs for now, later we may support some more
+  LUMIERA_PLUGIN_TYPE(LUA, ".lua")
+  LUMIERA_PLUGIN_TYPE(CSOURCE, ".c")
+*/
+
+#define LUMIERA_PLUGIN_TYPE(type, ext) LUMIERA_PLUGIN_##type,
 enum lumiera_plugin_type
   {
-    LUMIERA_PLUGIN_NULL,
-    LUMIERA_PLUGIN_DYNLIB,
-    LUMIERA_PLUGIN_CSOURCE
+    LUMIERA_PLUGIN_TYPES
+    LUMIERA_PLUGIN_NONE
   };
+#undef LUMIERA_PLUGIN_TYPE
 
-static const struct
-{
-  const char* const ext;
-  enum lumiera_plugin_type type;
-} lumiera_plugin_extensions [] =
+#define LUMIERA_PLUGIN_TYPE(type, ext) ext,
+static const char* const lumiera_plugin_ext[] =
   {
-    {"so",       LUMIERA_PLUGIN_DYNLIB},
-    {"o",        LUMIERA_PLUGIN_DYNLIB},
-    {"c",        LUMIERA_PLUGIN_CSOURCE},
-    /* extend here */
-    {NULL,       LUMIERA_PLUGIN_NULL}
+    LUMIERA_PLUGIN_TYPES
+    NULL
   };
+#undef LUMIERA_PLUGIN_TYPE
 
 
-struct lumiera_plugin
+
+
+struct lumiera_plugin_struct
 {
-  /* short name as queried ("effects/audio/normalize") used for sorting/finding */
-  const char* name;
+  psplaynode node;
 
   /* long names as looked up ("/usr/local/lib/lumiera/plugins/effects/audio/normalize.so") */
-  const char* pathname;
+  const char* name;
 
   /* use count for all interfaces of this plugin */
-  unsigned use_count;
+  unsigned refcnt;
 
   /* time when the last open or close action happened */
   time_t last;
@@ -96,242 +96,124 @@ struct lumiera_plugin
 };
 
 
-/* global plugin registry */
-void* lumiera_plugin_registry = NULL;
 
-/* plugin operations are protected by one big mutex */
-pthread_mutex_t lumiera_plugin_mutex = PTHREAD_MUTEX_INITIALIZER;
-
-/**
- * the compare function for the registry tree.
- * Compares the names of two struct lumiera_plugin.
- * @return 0 if a and b are equal, just like strcmp. */
-static int
-lumiera_plugin_name_cmp (const void* a, const void* b)
-{
-  return strcmp (((struct lumiera_plugin*) a)->name, ((struct lumiera_plugin*) b)->name);
-}
-
-void
-lumiera_init_plugin (void)
-{
-  NOBUG_INIT_FLAG (lumiera_plugin);
-}
-
-/**
- * Find and set pathname for the plugin.
- * Searches through given path for given plugin, trying to find the file's location in the filesystem.
- * If found, self->pathname will be set to the found plugin file.
- * @param self The lumiera_plugin to open look for.
- * @param path The path to search trough (paths seperated by ":")
- * @return 0 on success. -1 on error, or if plugin not found in path.
- */
 int
-lumiera_plugin_lookup (struct lumiera_plugin* self, const char* path)
+lumiera_plugin_discover (LumieraPlugin (*callback_load)(const char* plugin),
+                         int (*callback_register) (LumieraPlugin))
 {
-  if (!path)
-    return -1;
+  TRACE (plugin);
+  REQUIRE (callback_load);
+  REQUIRE (callback_register);
 
-  if (strlen(path) > 1023)
-    return -1;        /*TODO error handling*/
-
-  char tpath[1024];
-  TODO("dunno if PATH_MAX may be undefined (in case arbitary lengths are supported), I check that later");
-  char pathname[1024] = {0};
-  char* tmp;
-
-  strcpy(tpath, path);
-
-  /*for each in path*/
-  for (char* tok = strtok_r (tpath, ":", &tmp); tok; tok = strtok_r (NULL, ":", &tmp))
+  /* construct glob trail {.so,.c,.foo} ... */
+  static char* exts_globs = NULL;
+  if (!exts_globs)
     {
-      /*for each extension*/
-      for (int i = 0; lumiera_plugin_extensions[i].ext; ++i)
+      size_t exts_sz = 4; /* / * { } \0 less one comma */
+      const char*const* itr = lumiera_plugin_ext;
+      while (*itr)
         {
-          /* path/name.extension */
-          int r = snprintf(pathname, 1024, "%s/%s.%s", tok, self->name, lumiera_plugin_extensions[i].ext);
-          if (r >= 1024)
-            return -1; /*TODO error handling, name too long*/
+          exts_sz += strlen (*itr) + 1;
+          ++itr;
+        }
 
-          TRACE (lumiera_plugin, "trying %s", pathname);
+      exts_globs = lumiera_malloc (exts_sz);
+      *exts_globs = '\0';
 
-          if (!access(pathname, R_OK))
+      itr = lumiera_plugin_ext;
+      strcat (exts_globs, "/*{");
+
+      while (*itr)
+        {
+          strcat (exts_globs, *itr);
+          strcat (exts_globs, ",");
+          ++itr;
+        }
+      exts_globs[exts_sz-2] = '}';
+      TRACE (plugin, "initialized extension glob to '%s'", exts_globs);
+    }
+
+  const char* path;
+  unsigned i = 0;
+  int flags = GLOB_PERIOD|GLOB_BRACE|GLOB_TILDE_CHECK;
+  glob_t globs;
+
+  while ((path = lumiera_config_wordlist_get_nth ("plugin.path", i, ":")))
+    {
+      path = lumiera_tmpbuf_snprintf (SIZE_MAX,"%s%s", path, exts_globs);
+      TRACE (plugin, "globbing path '%s'", path);
+      int ret = glob (path, flags, NULL, &globs);
+      if (ret == GLOB_NOSPACE)
+        LUMIERA_DIE (NO_MEMORY);
+
+      flags |= GLOB_APPEND;
+      ++i;
+    }
+
+  LUMIERA_RECMUTEX_SECTION (plugin, &lumiera_interface_mutex)
+    {
+      for (char** itr = globs.gl_pathv; *itr; ++itr)
+        {
+
+          if (!psplay_find (lumiera_pluginregistry, *itr, 100))
             {
-              /* got it */
-              TRACE (lumiera_plugin, "found %s", pathname);
-              self->pathname = lumiera_strndup (pathname, PATH_MAX);
+              TRACE (plugin, "found new plugin '%s'", *itr);
 
-              self->type = lumiera_plugin_extensions[i].type;
-              return 0;
+              LumieraPlugin plugin = callback_load (*itr);
+              if (plugin)
+                callback_register (plugin);
             }
         }
     }
-  return -1; /* plugin not found */
+
+  globfree (&globs);
+
+  return !lumiera_error_peek ();
 }
 
 
-struct lumiera_interface*
-lumiera_interface_open (const char* name, const char* interface, size_t min_revision)
+
+
+
+LumieraPlugin
+lumiera_plugin_load (const char* plugin)
 {
-  //REQUIRE (min_revision > sizeof(struct lumiera_interface), "try to use an empty interface eh?");
-  REQUIRE (interface, "interface name must be given");
+  TRACE (plugin);
+  UNIMPLEMENTED();
+  (void) plugin;
 
-  pthread_mutex_lock (&lumiera_plugin_mutex);
-
-  struct lumiera_plugin plugin;
-  struct lumiera_plugin** found;
-
-  plugin.name = name; /* for searching */
-
-  found = tsearch (&plugin, &lumiera_plugin_registry, lumiera_plugin_name_cmp);
-  if (!found)
-    LUMIERA_DIE (NO_MEMORY);
-
-  if (*found == &plugin)
-    {
-      NOTICE (lumiera_plugin, "new plugin");
-
-      /* now really create new item */
-      *found = lumiera_malloc (sizeof (struct lumiera_plugin));
-
-      if (name) /* NULL is main app, no lookup needed */
-        {
-          /*lookup for $LUMIERA_PLUGIN_PATH*/
-          (*found)->name = lumiera_strndup (name, PATH_MAX);
-
-          if (!!lumiera_plugin_lookup (*found, getenv("LUMIERA_PLUGIN_PATH"))
-#ifdef LUMIERA_PLUGIN_PATH
-              /* else lookup for -DLUMIERA_PLUGIN_PATH */
-              && !!lumiera_plugin_lookup (*found, LUMIERA_PLUGIN_PATH)
-#endif
-              )
-            {
-              LUMIERA_ERROR_SET (lumiera_plugin, PLUGIN_NFILE);
-              goto elookup;
-            }
-        }
-      else
-        {
-          (*found)->name = NULL;
-          (*found)->pathname = NULL;
-        }
-
-      (*found)->use_count = 0;
-
-      PLANNED("if .so like then dlopen; else if .c like tcc compile");
-      TODO("factor dlopen and dlsym out");
-
-      TRACE(lumiera_plugin, "trying to open %s", (*found)->pathname);
-
-      (*found)->handle = dlopen ((*found)->pathname, RTLD_LAZY|RTLD_LOCAL);
-      if (!(*found)->handle)
-        {
-          ERROR (lumiera_plugin, "dlopen failed: %s", dlerror());
-          LUMIERA_ERROR_SET (lumiera_plugin, PLUGIN_DLOPEN);
-          goto edlopen;
-        }
-
-      /* if the plugin defines a 'lumiera_plugin_init' function, we call it, must return 0 on success */
-      int (*init)(void) = dlsym((*found)->handle, "lumiera_plugin_init");
-      if (init && init())
-        {
-          //ERROR (lumiera_plugin, "lumiera_plugin_init failed: %s: %s", name, interface);
-          LUMIERA_ERROR_SET (lumiera_plugin, PLUGIN_HOOK);
-          goto einit;
-        }
-    }
-  /* we have the plugin, now get the interface descriptor */
-  struct lumiera_interface* ret;
-
-  dlerror();
-  ret = dlsym ((*found)->handle, interface);
-
-  const char *dlerr = dlerror();
-  TRACE(lumiera_plugin, "%s", dlerr);
-  TODO ("need some way to tell 'interface not provided by plugin', maybe lumiera_plugin_error()?");
-  if (dlerr)
-    {
-      //ERROR (lumiera_plugin, "plugin %s doesnt provide interface %s", name, interface);
-      LUMIERA_ERROR_SET (lumiera_plugin, PLUGIN_NIFACE);
-      goto edlsym;
-    }
-
-  /* is the interface older than required? */
-  if (ret->size < min_revision)
-    {
-      ERROR (lumiera_plugin, "plugin %s provides older interface %s revision than required", name, interface);
-      LUMIERA_ERROR_SET (lumiera_plugin, PLUGIN_REVISION);
-      goto erevision;
-    }
-
-  ret->plugin = *found;
-
-  /* if the interface provides a 'open' function, call it now, must return 0 on success */
-  if (ret->open && ret->open())
-    {
-      ERROR (lumiera_plugin, "open hook indicated an error");
-      LUMIERA_ERROR_SET (lumiera_plugin, PLUGIN_HOOK);
-      goto eopen;
-    }
-
-  (*found)->use_count++;
-  (*found)->last = time (NULL);
-  ret->use_count++;
-
-  pthread_mutex_unlock (&lumiera_plugin_mutex);
-  return ret;
-
-  /* Error cleanup */
- einit:
-  dlclose((*found)->handle);
- eopen:
- erevision:
- edlsym:
- edlopen:
- elookup:
-  free ((char*)(*found)->name);
-  free (*found);
-  *found = &plugin;
-  tdelete (&plugin, &lumiera_plugin_registry, lumiera_plugin_name_cmp);
-  pthread_mutex_unlock (&lumiera_plugin_mutex);
   return NULL;
 }
 
-void
-lumiera_interface_close (void* ptr)
+
+int
+lumiera_plugin_register (LumieraPlugin plugin)
 {
-  TRACE (lumiera_plugin, "%p", ptr);
-  if(!ptr)
-    return;
+  TRACE (plugin);
+  UNIMPLEMENTED();
 
-  struct lumiera_interface* self = (struct lumiera_interface*) ptr;
-
-  pthread_mutex_lock (&lumiera_plugin_mutex);
-
-  struct lumiera_plugin* plugin = self->plugin;
-  
-  plugin->use_count--;
-  self->use_count--;
-
-  /* if the interface provides a 'close' function, call it now */
-  if (self->close)
-    self->close();
-
-  /* plugin not longer in use, unload it */
-  if (!plugin->use_count)
+  LUMIERA_RECMUTEX_SECTION (plugin, &lumiera_interface_mutex)
     {
-      TODO ("we dont want to close here, instead store time of recent use and make a expire run, already planned in my head");
+      (void) plugin;
 
-      /* if the plugin defines a 'lumiera_plugin_destroy' function, we call it */
-      int (*destroy)(void) = dlsym(plugin->handle, "lumiera_plugin_destroy");
-      if (destroy)
-        destroy();
-
-      /* and now cleanup */
-      tdelete (plugin, &lumiera_plugin_registry, lumiera_plugin_name_cmp);
-      free ((char*)plugin->name);
-      dlclose(plugin->handle);
-      free (plugin);
     }
-  pthread_mutex_unlock (&lumiera_plugin_mutex);
+  return 0;
 }
+
+
+
+
+
+int
+lumiera_plugin_cmp_fn (const void* keya, const void* keyb)
+{
+  return strcmp ((const char*)keya, (const char*)keyb);
+}
+
+
+const void*
+lumiera_plugin_key_fn (const PSplaynode node)
+{
+  return ((LumieraPlugin)node)->name;
+}
+
diff --git a/src/backend/plugin.h b/src/backend/plugin.h
index 7e17afc18..8c0e5e7ae 100644
--- a/src/backend/plugin.h
+++ b/src/backend/plugin.h
@@ -21,111 +21,64 @@
 #ifndef LUMIERA_PLUGIN_H
 #define LUMIERA_PLUGIN_H
 
-#ifdef __cplusplus
-extern "C" {
-#elif 0
-} /*eek, fixes emacs indenting for now*/
-#endif
 
 #include <stdlib.h>
 #include <nobug.h>
 
-#include "error.h"
+#include "lib/error.h"
 
 /**
  * @file
- * Plugin loader, header.
+ * Lumiera plugins defines 'interfaces' as shown in interface.h, the plugin system handles the loading
+ * of all kinds of plugins under the hood, invoked from the interface system. Anything defined here is
+ * called internally and should not be used by other parts of the application.
  */
 
 
-NOBUG_DECLARE_FLAG (lumiera_plugin);
+LUMIERA_ERROR_DECLARE(PLUGIN_DLOPEN);
+LUMIERA_ERROR_DECLARE(PLUGIN_PLUGINPATH);
+
+
+NOBUG_DECLARE_FLAG (plugin);
 
 /* tool macros*/
-#define LUMIERA_INTERFACE_TYPE(name, version) struct lumiera_interface_##name##_##version
-#define LUMIERA_INTERFACE_CAST(name, version) (LUMIERA_INTERFACE_TYPE(name, version)*)
-
-/* Interface definition */
-#define LUMIERA_INTERFACE(name, version, ...)   \
-LUMIERA_INTERFACE_TYPE(name, version)           \
-{                                               \
-  struct lumiera_interface interface_header_; \
-  __VA_ARGS__                                   \
-}
-
-#define LUMIERA_INTERFACE_PROTO(ret, name, params)  ret (*name) params;
-
-/* Interface instantiation */
-#define LUMIERA_INTERFACE_IMPLEMENT(iname, version, name, open, close, ...)  \
-LUMIERA_INTERFACE_TYPE(iname, version) name##_##version =                    \
-{                                                                            \
-  {                                                                          \
-    version,                                                                 \
-    sizeof(LUMIERA_INTERFACE_TYPE(iname, version)),                          \
-    NULL,                                                                    \
-    0,                                                                       \
-    open,                                                                    \
-    close                                                                    \
-  },                                                                         \
-  __VA_ARGS__                                                                \
-}
 
 
+struct lumiera_plugin_struct;
+typedef struct lumiera_plugin_struct lumiera_plugin;
+typedef lumiera_plugin* LumieraPlugin;
 
-/* internally used */
-struct lumiera_plugin;
 
-/**
- * This is the header for any interface exported by plugins.
- * Real interfaces append their functions at the end. There are few standard functions on each Interface
- * Every function is required to be implemnted.
- */
-struct lumiera_interface
-{
-  /// interface version number
-  unsigned version;
-  /// size of the full structure is used to determine the revision (adding a new function increments the size)
-  size_t size;
-  /// back reference to plugin
-  struct lumiera_plugin* plugin;
-  /// incremented for each user of this interface and decremented when closed
-  unsigned use_count;
+int
+lumiera_plugin_cmp_fn (const void* keya, const void* keyb);
+
+const void*
+lumiera_plugin_key_fn (const PSplaynode node);
+
+
+LumieraPlugin
+lumiera_plugin_load (const char* plugin);
+
+
+int
+lumiera_plugin_register (LumieraPlugin);
 
-  /// called for each open of this interface
-  int (*open)(void);
-  /// called for each close of this interface
-  int (*close)(void);
-};
 
-/**
- * Initialize the plugin system.
- * always succeeds or aborts
- */
-void
-lumiera_init_plugin (void);
 
 
 /**
- * Make an interface available.
- * To use an interface provided by a plugin it must be opened first. It is allowed to open an interface 
- * more than once. Each open must be paired with a close.
- * @param name name of the plugin to use.
- * @param interface name of the interface to open.
- * @param min_revision the size of the interface structure is used as measure of a minimal required 
- * revision (new functions are appended at the end)
- * @return handle to the interface or NULL in case of a error. The application shall cast this handle to
- * the actual interface type.
+ * discover new plugins
+ * traverses the configured plugin dirs and calls the callback_load function for any plugin
+ * not actually loaded. If callback_load returns a plugin (and not NULL) then this is feed to
+ * the callback_register function.
  */
-struct lumiera_interface*
-lumiera_interface_open (const char* plugin, const char* name, size_t min_revision);
+int
+lumiera_plugin_discover (LumieraPlugin (*callback_load)(const char* plugin),
+                         int (*callback_register) (LumieraPlugin));
+
+
 
 
-/**
- * Close an interface. Does not free associated resources
- * Calling this function with self==NULL is legal. Every interface handle must be closed only once.
- * @param ptr interface to be closed
- */
-void
-lumiera_interface_close (void* self);
 
 /**
  * Tries to unload a plugin.
@@ -136,22 +89,5 @@ lumiera_interface_close (void* self);
 int
 lumiera_plugin_unload (const char* plugin);
 
-/**
- * Tries to unload plugins which are not in use.
- * Calls lumiera_plugin_unload() for each Plugin which is not used for more than age seconds.
- * This function might be infrequently called by the scheduler to remove things which are not needed.
- * @param age timeout in seconds when to unload plugins
- */
-void
-lumiera_plugin_expire (time_t age);
 
-LUMIERA_ERROR_DECLARE(PLUGIN_DLOPEN);
-LUMIERA_ERROR_DECLARE(PLUGIN_HOOK);
-LUMIERA_ERROR_DECLARE(PLUGIN_NFILE);
-LUMIERA_ERROR_DECLARE(PLUGIN_NIFACE);
-LUMIERA_ERROR_DECLARE(PLUGIN_REVISION);
-
-#ifdef __cplusplus
-} /* extern "C" */
-#endif
 #endif /* LUMIERA_PLUGIN_H */
diff --git a/src/lib/error.c b/src/lib/error.c
index 1d3fb50c3..6007dcbdb 100644
--- a/src/lib/error.c
+++ b/src/lib/error.c
@@ -60,7 +60,7 @@ lumiera_error_set (lumiera_err nerr)
 
 
 lumiera_err
-lumiera_error ()
+lumiera_error (void)
 {
   pthread_once (&lumiera_error_initialized, lumiera_error_tls_init);
 
@@ -69,3 +69,12 @@ lumiera_error ()
     pthread_setspecific (lumiera_error_tls, NULL);
   return err;
 }
+
+
+lumiera_err
+lumiera_error_peek (void)
+{
+  pthread_once (&lumiera_error_initialized, lumiera_error_tls_init);
+
+  return pthread_getspecific (lumiera_error_tls);
+}
diff --git a/src/lib/error.h b/src/lib/error.h
index 5c4a8c145..5ad8a3142 100644
--- a/src/lib/error.h
+++ b/src/lib/error.h
@@ -88,7 +88,19 @@ lumiera_error_set (lumiera_err err);
  * @return pointer to any pending error of this thread, NULL if no error is pending
  */
 lumiera_err
-lumiera_error ();
+lumiera_error (void);
+
+
+/**
+ * Check current error state without clearing it
+ * Please avoid this function and use lumiera_error() if possible. Errors must be cleared else certain
+ * parts of the application refuse to cooperate with you. This shall only be used to decide if one
+ * wants to barf out of a loop or subroutine to deliver the error to a higher level.
+ * @return pointer to any pending error of this thread, NULL if no error is pending
+ */
+lumiera_err
+lumiera_error_peek (void);
+
 
 /*
   predefined errors
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 66367ffb4..a88377b92 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -72,6 +72,6 @@ check_PROGRAMS += test-interfaces
 test_interfaces_SOURCES = $(tests_srcdir)/backend/test-interfaces.c
 test_interfaces_CPPFLAGS = $(AM_CPPFLAGS) -std=gnu99 -Wall -Werror
 test_interfaces_LDADD = liblumibackend.a liblumiera.a $(NOBUGMT_LUMIERA_LIBS) -lm
-test_interfaces_DEPENDENCIES = examplepluginc.la
+test_interfaces_DEPENDENCIES = examplepluginc.la liblumibackend.a liblumiera.a
 
 TESTS = $(tests_srcdir)/test.sh
diff --git a/tests/backend/test-config.c b/tests/backend/test-config.c
index 506801454..120fc57d7 100644
--- a/tests/backend/test-config.c
+++ b/tests/backend/test-config.c
@@ -330,7 +330,7 @@ TEST ("wordlist_get_nth")
   if (!lumiera_config_wordlist_set (argv[2], &argv[3]))
     printf ("failed setting word '%s=%s': %s\n", argv[2], argv[3], lumiera_error ());
 
-  const char* word = lumiera_config_wordlist_get_nth (argv[2], atoi (argv[4]));
+  const char* word = lumiera_config_wordlist_get_nth (argv[2], atoi (argv[4]), " \t,;");
 
   printf ("'%s'\n", word?word:"NULL");
 
@@ -349,7 +349,7 @@ TEST ("wordlist_find")
   if (!lumiera_config_wordlist_set (argv[2], &argv[3]))
     printf ("failed setting word '%s=%s': %s\n", argv[2], argv[3], lumiera_error ());
 
-  int n = lumiera_config_wordlist_find (argv[2], argv[4]);
+  int n = lumiera_config_wordlist_find (argv[2], argv[4], " \t,;");
 
   printf ("'%d'\n", n);
 
@@ -370,7 +370,7 @@ TEST ("wordlist_replace")
   if (!lumiera_config_wordlist_set (argv[2], &argv[3]))
     printf ("failed setting word '%s=%s': %s\n", argv[2], argv[3], lumiera_error ());
 
-  const char* wordlist = lumiera_config_wordlist_replace (argv[2], argv[4], *argv[5]?argv[5]:NULL, *argv[6]?argv[6]:NULL);
+  const char* wordlist = lumiera_config_wordlist_replace (argv[2], argv[4], *argv[5]?argv[5]:NULL, *argv[6]?argv[6]:NULL, " \t,;");
 
   if (wordlist)
     printf ("'%s'\n", wordlist);
@@ -393,13 +393,13 @@ TEST ("wordlist_add")
   if (!lumiera_config_wordlist_set (argv[2], &argv[3]))
     printf ("failed setting word '%s=%s': %s\n", argv[2], argv[3], lumiera_error ());
 
-  const char* wordlist = lumiera_config_wordlist_add (argv[2], argv[4]);
+  const char* wordlist = lumiera_config_wordlist_add (argv[2], argv[4], " \t,;");
   if (wordlist)
     printf ("'%s'\n", wordlist);
   else
     printf ("%s\n", lumiera_error ());
 
-  wordlist = lumiera_config_wordlist_add (argv[2], argv[5]);
+  wordlist = lumiera_config_wordlist_add (argv[2], argv[5], " \t,;");
   if (wordlist)
     printf ("'%s'\n", wordlist);
   else
diff --git a/tests/backend/test-interfaces.c b/tests/backend/test-interfaces.c
index 8d7c377e8..110c6a855 100644
--- a/tests/backend/test-interfaces.c
+++ b/tests/backend/test-interfaces.c
@@ -298,7 +298,7 @@ TEST ("basic")
 {
   lumiera_interfaceregistry_init ();
 
-  lumiera_interfaceregistry_bulkregister_interfaces (interfaces_defined_here());
+  lumiera_interfaceregistry_bulkregister_interfaces (interfaces_defined_here(), NULL);
 
 
   /* some ugly lowlevel handling tests */
@@ -321,7 +321,7 @@ TEST ("basic")
 TEST ("open_close")
 {
   lumiera_interfaceregistry_init ();
-  lumiera_interfaceregistry_bulkregister_interfaces (interfaces_defined_here());
+  lumiera_interfaceregistry_bulkregister_interfaces (interfaces_defined_here(), NULL);
 
   LUMIERA_INTERFACE_HANDLE(lumieraorg_testexample_one, 0) handle =
     LUMIERA_INTERFACE_OPEN (lumieraorg_testexample_one, 0, 0, lumieraorg_first_test);
@@ -338,7 +338,7 @@ TEST ("open_close")
 TEST ("dependencies_one")
 {
   lumiera_interfaceregistry_init ();
-  lumiera_interfaceregistry_bulkregister_interfaces (dependencytests());
+  lumiera_interfaceregistry_bulkregister_interfaces (dependencytests(), NULL);
 
   LUMIERA_INTERFACE_HANDLE(lumieraorg_testexample_void, 0) handle =
     LUMIERA_INTERFACE_OPEN (lumieraorg_testexample_void, 0, 0, lumieraorg_dependencytest_one);
@@ -356,7 +356,7 @@ TEST ("dependencies_one")
 TEST ("dependencies_two")
 {
   lumiera_interfaceregistry_init ();
-  lumiera_interfaceregistry_bulkregister_interfaces (dependencytests());
+  lumiera_interfaceregistry_bulkregister_interfaces (dependencytests(), NULL);
 
   LUMIERA_INTERFACE_HANDLE(lumieraorg_testexample_void, 0) handle =
     LUMIERA_INTERFACE_OPEN (lumieraorg_testexample_void, 0, 0, lumieraorg_dependencytest_two);
@@ -373,7 +373,7 @@ TEST ("dependencies_two")
 TEST ("dependencies_three")
 {
   lumiera_interfaceregistry_init ();
-  lumiera_interfaceregistry_bulkregister_interfaces (dependencytests());
+  lumiera_interfaceregistry_bulkregister_interfaces (dependencytests(), NULL);
 
   LUMIERA_INTERFACE_HANDLE(lumieraorg_testexample_void, 0) handle =
     LUMIERA_INTERFACE_OPEN (lumieraorg_testexample_void, 0, 0, lumieraorg_dependencytest_three);
@@ -391,7 +391,7 @@ TEST ("dependencies_three")
 TEST ("dependencies_four")
 {
   lumiera_interfaceregistry_init ();
-  lumiera_interfaceregistry_bulkregister_interfaces (dependencytests());
+  lumiera_interfaceregistry_bulkregister_interfaces (dependencytests(), NULL);
 
   LUMIERA_INTERFACE_HANDLE(lumieraorg_testexample_void, 0) handle =
     LUMIERA_INTERFACE_OPEN (lumieraorg_testexample_void, 0, 0, lumieraorg_dependencytest_four);
@@ -410,7 +410,7 @@ TEST ("dependencies_four")
 TEST ("dependencies_all")
 {
   lumiera_interfaceregistry_init ();
-  lumiera_interfaceregistry_bulkregister_interfaces (dependencytests());
+  lumiera_interfaceregistry_bulkregister_interfaces (dependencytests(), NULL);
 
   TRACE (tests, "OPEN one");
   LUMIERA_INTERFACE_HANDLE(lumieraorg_testexample_void, 0) handle_one =