diff --git a/CMakeLists.txt b/CMakeLists.txt
index f233ede..de2c9ac 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -3,6 +3,7 @@ project(slcl)
 add_executable(${PROJECT_NAME}
     auth.c
     base64.c
+    cftw.c
     handler.c
     html.c
     http.c
diff --git a/Makefile b/Makefile
index 7001c0b..e29c8ac 100644
--- a/Makefile
+++ b/Makefile
@@ -11,6 +11,7 @@ DEPS = $(OBJECTS:.o=.d)
 OBJECTS = \
 	auth.o \
 	base64.o \
+	cftw.o \
 	handler.o \
 	html.o \
 	http.o \
diff --git a/cftw.c b/cftw.c
new file mode 100644
index 0000000..921a12e
--- /dev/null
+++ b/cftw.c
@@ -0,0 +1,61 @@
+#include "cftw.h"
+#include <dynstr.h>
+#include <dirent.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+
+int cftw(const char *const dirpath, int (*const fn)(const char *,
+    const struct stat *, void *), void *const user)
+{
+    DIR *const d = opendir(dirpath);
+    struct dirent *de;
+
+    if (!d)
+    {
+        fprintf(stderr, "%s: opendir(2): %s\n", __func__, strerror(errno));
+        return -1;
+    }
+
+    while ((de = readdir(d)))
+    {
+        const char *const path = de->d_name;
+
+        if (!strcmp(path, ".") || !strcmp(path, ".."))
+            continue;
+
+        struct stat sb;
+        struct dynstr d;
+
+        dynstr_init(&d);
+
+        if (dynstr_append(&d, "%s/%s", dirpath, path))
+        {
+            fprintf(stderr, "%s: dynstr_append failed\n", __func__);
+            return -1;
+        }
+
+        const int r = stat(d.str, &sb);
+        int ret = -1;
+
+        if (r)
+            fprintf(stderr, "%s: stat(2) %s: %s\n",
+                __func__, path, strerror(errno));
+        else if (S_ISDIR(sb.st_mode))
+            ret = cftw(d.str, fn, user);
+        else if (S_ISREG(sb.st_mode))
+            ret = fn(d.str, &sb, user);
+        else
+            fprintf(stderr, "%s: unexpected st_mode %ju\n",
+                __func__, (uintmax_t)sb.st_mode);
+
+        dynstr_free(&d);
+
+        if (ret)
+            return ret;
+    }
+
+    return 0;
+}
diff --git a/cftw.h b/cftw.h
new file mode 100644
index 0000000..612451e
--- /dev/null
+++ b/cftw.h
@@ -0,0 +1,11 @@
+#ifndef CFTW_H
+#define CFTW_H
+
+#include <sys/stat.h>
+
+/* Thread-safe variant of ftw(3) and nftw(3) that allows passing an
+ * opaque pointer and removes some unneeded parameters. */
+int cftw(const char *dirpath, int (*fn)(const char *fpath,
+    const struct stat *sb, void *user), void *user);
+
+#endif /* CFTW_H */