diff --git a/src/mod_magnet.c b/src/mod_magnet.c
index 6ec506d1..b8657b40 100644
--- a/src/mod_magnet.c
+++ b/src/mod_magnet.c
@@ -870,6 +870,18 @@ static handler_t magnet_attract(request_st * const r, plugin_data * const p, buf
 	/* get the script-context */
 	L = script_cache_get_script(&p->cache, name, r->conf.etag_flags);
 
+	if (NULL == L) {
+		log_perror(r->conf.errh, __FILE__, __LINE__,
+		  "loading script %s failed", name->ptr);
+
+		if (p->conf.stage != -1) { /* skip for response-start */
+			r->http_status = 500;
+			r->handler_module = NULL;
+		}
+
+		return HANDLER_FINISHED;
+	}
+
 	if (lua_isstring(L, -1)) {
 		log_error(r->conf.errh, __FILE__, __LINE__,
 		  "loading script %s failed: %s", name->ptr, lua_tostring(L, -1));
diff --git a/src/mod_magnet_cache.c b/src/mod_magnet_cache.c
index 6bd54be8..28cc461e 100644
--- a/src/mod_magnet_cache.c
+++ b/src/mod_magnet_cache.c
@@ -1,11 +1,11 @@
 #include "first.h"
 
 #include "mod_magnet_cache.h"
-#include "log.h"
 #include "stat_cache.h"
 
-#include "sys-time.h"
+#include <errno.h>
 #include <stdlib.h>
+#include <unistd.h>     /* read() */
 
 #include <lualib.h>
 #include <lauxlib.h>
@@ -22,7 +22,8 @@ __attribute_cold__
 static void script_free(script *sc)
 {
     if (!sc) return;
-    lua_pop(sc->L, 1); /* the function copy */
+    if (lua_gettop(sc->L) != 0)
+        lua_pop(sc->L, 1); /* the function copy */
     lua_close(sc->L);
     free(sc->name.ptr);
     free(sc->etag.ptr);
@@ -46,67 +47,99 @@ void script_cache_free_data(script_cache *p)
     free(p->ptr);
 }
 
+__attribute_cold__
+__attribute_noinline__
+static lua_State *script_cache_load_script(script * const sc, int etag_flags)
+{
+    /* read file and use luaL_loadbuffer()
+     * eliminate TOC-TOU race w/ independent stat() in stat_cache_get_entry() */
+
+    stat_cache_entry * const sce = stat_cache_get_entry_open(&sc->name, 1);
+    buffer_clear(&sc->etag);
+    if (NULL == sce || sce->fd < 0) {
+        /*(sce->fd < 0 might indicate empty file, which is not a valid script)*/
+        if (NULL != sce) errno = EBADF;
+        return NULL;
+    }
+    const buffer * const etag = stat_cache_etag_get(sce, etag_flags);
+    if (etag)
+        buffer_copy_buffer(&sc->etag, etag);
+
+    const off_t sz = sce->st.st_size;
+    char * const buf = malloc(sz);
+    force_assert(buf);
+
+    ssize_t rd = 0;
+    off_t off = 0;
+    do {
+        rd = read(sce->fd, buf+off, (size_t)(sz-off));
+    } while (rd > 0 ? (off += rd) != sz : rd < 0 && errno == EINTR);
+    if (off != sz) { /*(file truncated?)*/
+        if (rd >= 0) errno = EIO;
+        return NULL;
+    }
+
+    int rc = luaL_loadbuffer(sc->L, buf, (size_t)sz, sc->name.ptr);
+    free(buf);
+
+    if (0 != rc) {
+        /* oops, an error, return it */
+        return sc->L;
+    }
+
+    force_assert(lua_isfunction(sc->L, -1));
+    return sc->L;
+}
+
+__attribute_cold__
+static lua_State *script_cache_new_script(script_cache * const cache, const buffer * const name, int etag_flags)
+{
+    script * const sc = script_init();
+
+    if (cache->used == cache->size) {
+        cache->size += 16;
+        cache->ptr = realloc(cache->ptr, cache->size * sizeof(*(cache->ptr)));
+    }
+    cache->ptr[cache->used++] = sc;
+
+    buffer_copy_buffer(&sc->name, name);
+    sc->L = luaL_newstate();
+    luaL_openlibs(sc->L);
+    return script_cache_load_script(sc, etag_flags);
+}
+
+static lua_State *script_cache_check_script(script * const sc, int etag_flags)
+{
+    if (lua_gettop(sc->L) == 0)
+        return script_cache_load_script(sc, etag_flags);
+
+    force_assert(lua_gettop(sc->L) == 1);
+    force_assert(lua_isfunction(sc->L, -1));
+
+    stat_cache_entry * const sce = stat_cache_get_entry(&sc->name);
+    if (NULL == sce) {
+        lua_pop(sc->L, 1); /* pop the old function */
+        return script_cache_load_script(sc, etag_flags);
+    }
+
+    const buffer * const etag = stat_cache_etag_get(sce, etag_flags);
+    if (NULL == etag || !buffer_is_equal(&sc->etag, etag)) {
+        if (0 == etag_flags)
+            return sc->L;
+        /* the etag is outdated, reload the function */
+        lua_pop(sc->L, 1);
+        return script_cache_load_script(sc, etag_flags);
+    }
+
+    return sc->L;
+}
+
 lua_State *script_cache_get_script(script_cache *cache, const buffer *name, int etag_flags)
 {
-	script *sc = NULL;
-	stat_cache_entry *sce;
-
-	for (uint32_t i = 0; i < cache->used; ++i, sc = NULL) {
-		sc = cache->ptr[i];
-		if (!buffer_is_equal(name, &sc->name)) continue;
-
-			if (lua_gettop(sc->L) == 0) break;
-			force_assert(lua_gettop(sc->L) == 1);
-			sce = stat_cache_get_entry(&sc->name);
-			if (NULL == sce) {
-				lua_pop(sc->L, 1); /* pop the old function */
-				break;
-			}
-
-			const buffer *etag = stat_cache_etag_get(sce, etag_flags);
-			if (NULL == etag || !buffer_is_equal(&sc->etag, etag)) {
-				/* the etag is outdated, reload the function */
-				lua_pop(sc->L, 1);
-				break;
-			}
-
-			force_assert(lua_isfunction(sc->L, -1));
-
-			return sc->L;
-	}
-
-	/* if the script was script already loaded but either got changed or
-	 * failed to load last time */
-	if (sc == NULL) {
-		sc = script_init();
-
-		if (cache->used == cache->size) {
-			cache->size += 16;
-			cache->ptr = realloc(cache->ptr, cache->size * sizeof(*(cache->ptr)));
-		}
-
-		cache->ptr[cache->used++] = sc;
-
-		buffer_copy_buffer(&sc->name, name);
-
-		sc->L = luaL_newstate();
-		luaL_openlibs(sc->L);
-	}
-	buffer_clear(&sc->etag);
-
-	if (0 != luaL_loadfile(sc->L, name->ptr)) {
-		/* oops, an error, return it */
-		return sc->L;
-	}
-
-	sce = stat_cache_get_entry(&sc->name);
-	if (sce) {
-		const buffer *etag = stat_cache_etag_get(sce, etag_flags);
-		if (etag)
-			buffer_copy_buffer(&sc->etag, etag);
-	}
-
-	force_assert(lua_isfunction(sc->L, -1));
-
-	return sc->L;
+    for (uint32_t i = 0; i < cache->used; ++i) {
+        script * const sc = cache->ptr[i];
+        if (buffer_is_equal(&sc->name, name))
+            return script_cache_check_script(sc, etag_flags);
+    }
+    return script_cache_new_script(cache, name, etag_flags);
 }