diff --git a/src/Makefile b/src/Makefile
index 794e6bd..c65f663 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -1,11 +1,11 @@
 CC=cc
-override CFLAGS += -g -I. -Wall -Wpedantic -I ../deps/build/usr/local/include/
+override CFLAGS += -g -I. -Wall -Wpedantic -I ../deps/build/usr/local/include/ -std=gnu11
 LIBPATH = ../deps/build/usr/local/lib/
 LDFLAGS = -L $(LIBPATH)
 LDLIBS = -ljson-c -lcurl -lpthread -lGeoIP
 LDFLAGS += $(LDLIBS)
 CFLAGS_STATIC = $(CFLAGS) --static
-OBJ=helpers.o pfparser.o sysparser.o msgbuffer.o geo.o elasticsearch.o server.o config.o
+OBJ=helpers.o pfparser.o sysparser.o msgbuffer.o geo.o elasticsearch.o server.o vendor/argparse.o
 TESTS=$(patsubst %.c,%.test,$(wildcard tests/*.c))
 
 
diff --git a/src/config.c b/src/config.c
deleted file mode 100644
index bedcb69..0000000
--- a/src/config.c
+++ /dev/null
@@ -1,77 +0,0 @@
-#include <stdio.h>
-#include <string.h>
-#include <stdlib.h>
-#include <unistd.h>
-#include <sys/stat.h>
-#include <fcntl.h>
-#include <sys/mman.h>
-#include <errno.h>
-#include <json-c/json.h>
-#include "helpers.h"
-#include "config.h"
-#include "elasticsearch.h"
-
-
-char* get_strfield(json_object* obj, char* key) {
-    json_object *o_value = json_object_object_get(obj, key);
-    if(o_value == NULL)
-        return NULL;
-    const char* value = json_object_get_string(o_value);
-    if(value == NULL)
-        return NULL;
-    char* dest = malloc(strlen(value) + 1);
-    strcpy(dest, value);
-    return dest;
-}
-
-
-int get_intfield(json_object* obj, char* key) {
-    json_object *o_value = json_object_object_get(obj, key);
-    if(o_value == NULL)
-        return 0;
-    return json_object_get_int(o_value);
-}
-
-
-struct config* config_load(char* conf_path) {
-    int fd;
-    if((fd = open(conf_path, O_RDONLY)) == -1)
-        panic("Config load failed");
-
-    struct stat fsize = {0};
-    if(fstat(fd, &fsize) != 0)
-        die("Conf stat failed");
-
-    if(fsize.st_size == 0)
-        die("Empty config");
-
-    char* confdata = mmap(NULL, fsize.st_size, PROT_READ, MAP_SHARED, fd, 0);
-    if(confdata == MAP_FAILED)
-        panic("Failed to mmap conf");
-
-    json_object *j_conf;
-    if((j_conf = json_tokener_parse(confdata)) == NULL)
-        die("Json parse failed");
-
-    struct config* conf = calloc(1, sizeof(struct config));
-
-    if((conf->url = get_strfield(j_conf, "elasticsearch")) == NULL)
-        die("Config missing or invalid elasticsearch url");
-
-    if((conf->port = get_intfield(j_conf, "serverport")) == 0)
-        die("Config missing or invalid serverport number");
-
-    json_object_put(j_conf);
-
-    if(munmap(confdata, fsize.st_size) != 0)
-        panic("munmap failed");
-
-    close(fd);
-    return conf;
-}
-
-
-void config_free(struct config* conf) {
-    free(conf->url);
-    free(conf);
-}
diff --git a/src/config.h b/src/config.h
deleted file mode 100644
index f222cd1..0000000
--- a/src/config.h
+++ /dev/null
@@ -1,9 +0,0 @@
-struct config {
-    char* url;
-    int port;
-};
-
-
-struct config* config_load(char* conf_path);
-
-void config_free(struct config* conf);
diff --git a/src/main.c b/src/main.c
index ddcb585..8534f7a 100644
--- a/src/main.c
+++ b/src/main.c
@@ -2,36 +2,27 @@
 #include <stdlib.h>
 #include <assert.h>
 #include <limits.h>
-#include "config.h"
 #include "server.h"
 #include "helpers.h"
+#include "vendor/argparse.h"
 
 
-int main(int argc, char** argv) {
-    if (argc != 2) {
-        fprintf(stderr, "usage: %s <config.json>\n", argv[0]);
-        exit(1);
-    }
+int main(int argc, const char** argv) {
+    int port = -1;
+    char* url = NULL;
 
-    /*Parse port number to integer*/
-    /*char* portend;
-    unsigned int portl;
-    portl = strtol(argv[1], &portend, 10);
-    if (portend == NULL || portend == argv[1]) {
-        fprintf(stderr, "usage: %s <port>\n", argv[0]);
-        exit(1);
-    }
-    assert(portl < USHRT_MAX);
-    unsigned short port = (unsigned short)portl;*/
+    struct argparse_option options[] = {
+        OPT_HELP(),
+        OPT_INTEGER('p', "port", &port, "server port"),
+        OPT_STRING ('u', "url",  &url,  "elasticsearch url"),
+        OPT_END()
+    };
 
-    struct config* conf = config_load(argv[1]);
+    struct argparse argparse;
+    argparse_init(&argparse, options, NULL, 0);
+    argparse_parse(&argparse, argc, argv);
 
-    printf("url: %s\n", conf->url);
-    printf("port: %d\n", conf->port);
-
-    run_server(conf->port, conf->url);
-
-    config_free(conf);
+    run_server(port, url);
 
     exit(EXIT_SUCCESS);
 }
diff --git a/src/server.c b/src/server.c
index eefce11..12c3142 100644
--- a/src/server.c
+++ b/src/server.c
@@ -99,7 +99,7 @@ void* buffer_watch() {
     time_t last_flush = time(NULL);
     char* buffer = NULL;
     while(running) {
-        usleep(100 * 1000);
+        nanosleep(&(const struct timespec){0, 1000000}, NULL);
         time_t now = time(NULL);
 
         pthread_mutex_lock(&buflock);
diff --git a/src/vendor/argparse.c b/src/vendor/argparse.c
new file mode 100644
index 0000000..92ec391
--- /dev/null
+++ b/src/vendor/argparse.c
@@ -0,0 +1,385 @@
+/**
+ * Copyright (C) 2012-2015 Yecheng Fu <cofyc.jackson at gmail dot com>
+ * All rights reserved.
+ *
+ * Use of this source code is governed by a MIT-style license that can be found
+ * in the LICENSE file.
+ */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <assert.h>
+#include <errno.h>
+#include "argparse.h"
+
+#define OPT_UNSET 1
+#define OPT_LONG  (1 << 1)
+
+static const char *
+prefix_skip(const char *str, const char *prefix)
+{
+    size_t len = strlen(prefix);
+    return strncmp(str, prefix, len) ? NULL : str + len;
+}
+
+static int
+prefix_cmp(const char *str, const char *prefix)
+{
+    for (;; str++, prefix++)
+        if (!*prefix) {
+            return 0;
+        } else if (*str != *prefix) {
+            return (unsigned char)*prefix - (unsigned char)*str;
+        }
+}
+
+static void
+argparse_error(struct argparse *self, const struct argparse_option *opt,
+               const char *reason, int flags)
+{
+    (void)self;
+    if (flags & OPT_LONG) {
+        fprintf(stderr, "error: option `--%s` %s\n", opt->long_name, reason);
+    } else {
+        fprintf(stderr, "error: option `-%c` %s\n", opt->short_name, reason);
+    }
+    exit(1);
+}
+
+static int
+argparse_getvalue(struct argparse *self, const struct argparse_option *opt,
+                  int flags)
+{
+    const char *s = NULL;
+    if (!opt->value)
+        goto skipped;
+    switch (opt->type) {
+    case ARGPARSE_OPT_BOOLEAN:
+        if (flags & OPT_UNSET) {
+            *(int *)opt->value = *(int *)opt->value - 1;
+        } else {
+            *(int *)opt->value = *(int *)opt->value + 1;
+        }
+        if (*(int *)opt->value < 0) {
+            *(int *)opt->value = 0;
+        }
+        break;
+    case ARGPARSE_OPT_BIT:
+        if (flags & OPT_UNSET) {
+            *(int *)opt->value &= ~opt->data;
+        } else {
+            *(int *)opt->value |= opt->data;
+        }
+        break;
+    case ARGPARSE_OPT_STRING:
+        if (self->optvalue) {
+            *(const char **)opt->value = self->optvalue;
+            self->optvalue             = NULL;
+        } else if (self->argc > 1) {
+            self->argc--;
+            *(const char **)opt->value = *++self->argv;
+        } else {
+            argparse_error(self, opt, "requires a value", flags);
+        }
+        break;
+    case ARGPARSE_OPT_INTEGER:
+        errno = 0;
+        if (self->optvalue) {
+            *(int *)opt->value = strtol(self->optvalue, (char **)&s, 0);
+            self->optvalue     = NULL;
+        } else if (self->argc > 1) {
+            self->argc--;
+            *(int *)opt->value = strtol(*++self->argv, (char **)&s, 0);
+        } else {
+            argparse_error(self, opt, "requires a value", flags);
+        }
+        if (errno)
+            argparse_error(self, opt, strerror(errno), flags);
+        if (s[0] != '\0')
+            argparse_error(self, opt, "expects an integer value", flags);
+        break;
+    case ARGPARSE_OPT_FLOAT:
+        errno = 0;
+        if (self->optvalue) {
+            *(float *)opt->value = strtof(self->optvalue, (char **)&s);
+            self->optvalue     = NULL;
+        } else if (self->argc > 1) {
+            self->argc--;
+            *(float *)opt->value = strtof(*++self->argv, (char **)&s);
+        } else {
+            argparse_error(self, opt, "requires a value", flags);
+        }
+        if (errno)
+            argparse_error(self, opt, strerror(errno), flags);
+        if (s[0] != '\0')
+            argparse_error(self, opt, "expects a numerical value", flags);
+        break;
+    default:
+        assert(0);
+    }
+
+skipped:
+    if (opt->callback) {
+        return opt->callback(self, opt);
+    }
+
+    return 0;
+}
+
+static void
+argparse_options_check(const struct argparse_option *options)
+{
+    for (; options->type != ARGPARSE_OPT_END; options++) {
+        switch (options->type) {
+        case ARGPARSE_OPT_END:
+        case ARGPARSE_OPT_BOOLEAN:
+        case ARGPARSE_OPT_BIT:
+        case ARGPARSE_OPT_INTEGER:
+        case ARGPARSE_OPT_FLOAT:
+        case ARGPARSE_OPT_STRING:
+        case ARGPARSE_OPT_GROUP:
+            continue;
+        default:
+            fprintf(stderr, "wrong option type: %d", options->type);
+            break;
+        }
+    }
+}
+
+static int
+argparse_short_opt(struct argparse *self, const struct argparse_option *options)
+{
+    for (; options->type != ARGPARSE_OPT_END; options++) {
+        if (options->short_name == *self->optvalue) {
+            self->optvalue = self->optvalue[1] ? self->optvalue + 1 : NULL;
+            return argparse_getvalue(self, options, 0);
+        }
+    }
+    return -2;
+}
+
+static int
+argparse_long_opt(struct argparse *self, const struct argparse_option *options)
+{
+    for (; options->type != ARGPARSE_OPT_END; options++) {
+        const char *rest;
+        int opt_flags = 0;
+        if (!options->long_name)
+            continue;
+
+        rest = prefix_skip(self->argv[0] + 2, options->long_name);
+        if (!rest) {
+            // negation disabled?
+            if (options->flags & OPT_NONEG) {
+                continue;
+            }
+            // only OPT_BOOLEAN/OPT_BIT supports negation
+            if (options->type != ARGPARSE_OPT_BOOLEAN && options->type !=
+                ARGPARSE_OPT_BIT) {
+                continue;
+            }
+
+            if (prefix_cmp(self->argv[0] + 2, "no-")) {
+                continue;
+            }
+            rest = prefix_skip(self->argv[0] + 2 + 3, options->long_name);
+            if (!rest)
+                continue;
+            opt_flags |= OPT_UNSET;
+        }
+        if (*rest) {
+            if (*rest != '=')
+                continue;
+            self->optvalue = rest + 1;
+        }
+        return argparse_getvalue(self, options, opt_flags | OPT_LONG);
+    }
+    return -2;
+}
+
+int
+argparse_init(struct argparse *self, struct argparse_option *options,
+              const char *const *usages, int flags)
+{
+    memset(self, 0, sizeof(*self));
+    self->options     = options;
+    self->usages      = usages;
+    self->flags       = flags;
+    self->description = NULL;
+    self->epilog      = NULL;
+    return 0;
+}
+
+void
+argparse_describe(struct argparse *self, const char *description,
+                  const char *epilog)
+{
+    self->description = description;
+    self->epilog      = epilog;
+}
+
+int
+argparse_parse(struct argparse *self, int argc, const char **argv)
+{
+    self->argc = argc - 1;
+    self->argv = argv + 1;
+    self->out  = argv;
+
+    argparse_options_check(self->options);
+
+    for (; self->argc; self->argc--, self->argv++) {
+        const char *arg = self->argv[0];
+        if (arg[0] != '-' || !arg[1]) {
+            if (self->flags & ARGPARSE_STOP_AT_NON_OPTION) {
+                goto end;
+            }
+            // if it's not option or is a single char '-', copy verbatim
+            self->out[self->cpidx++] = self->argv[0];
+            continue;
+        }
+        // short option
+        if (arg[1] != '-') {
+            self->optvalue = arg + 1;
+            switch (argparse_short_opt(self, self->options)) {
+            case -1:
+                break;
+            case -2:
+                goto unknown;
+            }
+            while (self->optvalue) {
+                switch (argparse_short_opt(self, self->options)) {
+                case -1:
+                    break;
+                case -2:
+                    goto unknown;
+                }
+            }
+            continue;
+        }
+        // if '--' presents
+        if (!arg[2]) {
+            self->argc--;
+            self->argv++;
+            break;
+        }
+        // long option
+        switch (argparse_long_opt(self, self->options)) {
+        case -1:
+            break;
+        case -2:
+            goto unknown;
+        }
+        continue;
+
+unknown:
+        fprintf(stderr, "error: unknown option `%s`\n", self->argv[0]);
+        argparse_usage(self);
+        exit(1);
+    }
+
+end:
+    memmove(self->out + self->cpidx, self->argv,
+            self->argc * sizeof(*self->out));
+    self->out[self->cpidx + self->argc] = NULL;
+
+    return self->cpidx + self->argc;
+}
+
+void
+argparse_usage(struct argparse *self)
+{
+    if (self->usages) {
+        fprintf(stdout, "Usage: %s\n", *self->usages++);
+        while (*self->usages && **self->usages)
+            fprintf(stdout, "   or: %s\n", *self->usages++);
+    } else {
+        fprintf(stdout, "Usage:\n");
+    }
+
+    // print description
+    if (self->description)
+        fprintf(stdout, "%s\n", self->description);
+
+    fputc('\n', stdout);
+
+    const struct argparse_option *options;
+
+    // figure out best width
+    size_t usage_opts_width = 0;
+    size_t len;
+    options = self->options;
+    for (; options->type != ARGPARSE_OPT_END; options++) {
+        len = 0;
+        if ((options)->short_name) {
+            len += 2;
+        }
+        if ((options)->short_name && (options)->long_name) {
+            len += 2;           // separator ", "
+        }
+        if ((options)->long_name) {
+            len += strlen((options)->long_name) + 2;
+        }
+        if (options->type == ARGPARSE_OPT_INTEGER) {
+            len += strlen("=<int>");
+          }
+        if (options->type == ARGPARSE_OPT_FLOAT) {
+            len += strlen("=<flt>");
+        } else if (options->type == ARGPARSE_OPT_STRING) {
+            len += strlen("=<str>");
+        }
+        len = (len + 3) - ((len + 3) & 3);
+        if (usage_opts_width < len) {
+            usage_opts_width = len;
+        }
+    }
+    usage_opts_width += 4;      // 4 spaces prefix
+
+    options = self->options;
+    for (; options->type != ARGPARSE_OPT_END; options++) {
+        size_t pos = 0;
+        int pad    = 0;
+        if (options->type == ARGPARSE_OPT_GROUP) {
+            fputc('\n', stdout);
+            fprintf(stdout, "%s", options->help);
+            fputc('\n', stdout);
+            continue;
+        }
+        pos = fprintf(stdout, "    ");
+        if (options->short_name) {
+            pos += fprintf(stdout, "-%c", options->short_name);
+        }
+        if (options->long_name && options->short_name) {
+            pos += fprintf(stdout, ", ");
+        }
+        if (options->long_name) {
+            pos += fprintf(stdout, "--%s", options->long_name);
+        }
+        if (options->type == ARGPARSE_OPT_INTEGER) {
+            pos += fprintf(stdout, "=<int>");
+        }
+        if (options->type == ARGPARSE_OPT_FLOAT) {
+            pos += fprintf(stdout, "=<flt>");
+        } else if (options->type == ARGPARSE_OPT_STRING) {
+            pos += fprintf(stdout, "=<str>");
+        }
+        if (pos <= usage_opts_width) {
+            pad = usage_opts_width - pos;
+        } else {
+            fputc('\n', stdout);
+            pad = usage_opts_width;
+        }
+        fprintf(stdout, "%*s%s\n", pad + 2, "", options->help);
+    }
+
+    // print epilog
+    if (self->epilog)
+        fprintf(stdout, "%s\n", self->epilog);
+}
+
+int
+argparse_help_cb(struct argparse *self, const struct argparse_option *option)
+{
+    (void)option;
+    argparse_usage(self);
+    exit(0);
+}
diff --git a/src/vendor/argparse.h b/src/vendor/argparse.h
new file mode 100644
index 0000000..7fff31d
--- /dev/null
+++ b/src/vendor/argparse.h
@@ -0,0 +1,130 @@
+/**
+ * Copyright (C) 2012-2015 Yecheng Fu <cofyc.jackson at gmail dot com>
+ * All rights reserved.
+ *
+ * Use of this source code is governed by a MIT-style license that can be found
+ * in the LICENSE file.
+ */
+#ifndef ARGPARSE_H
+#define ARGPARSE_H
+
+/* For c++ compatibility */
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stdint.h>
+
+struct argparse;
+struct argparse_option;
+
+typedef int argparse_callback (struct argparse *self,
+                               const struct argparse_option *option);
+
+enum argparse_flag {
+    ARGPARSE_STOP_AT_NON_OPTION = 1,
+};
+
+enum argparse_option_type {
+    /* special */
+    ARGPARSE_OPT_END,
+    ARGPARSE_OPT_GROUP,
+    /* options with no arguments */
+    ARGPARSE_OPT_BOOLEAN,
+    ARGPARSE_OPT_BIT,
+    /* options with arguments (optional or required) */
+    ARGPARSE_OPT_INTEGER,
+    ARGPARSE_OPT_FLOAT,
+    ARGPARSE_OPT_STRING,
+};
+
+enum argparse_option_flags {
+    OPT_NONEG = 1,              /* disable negation */
+};
+
+/**
+ *  argparse option
+ *
+ *  `type`:
+ *    holds the type of the option, you must have an ARGPARSE_OPT_END last in your
+ *    array.
+ *
+ *  `short_name`:
+ *    the character to use as a short option name, '\0' if none.
+ *
+ *  `long_name`:
+ *    the long option name, without the leading dash, NULL if none.
+ *
+ *  `value`:
+ *    stores pointer to the value to be filled.
+ *
+ *  `help`:
+ *    the short help message associated to what the option does.
+ *    Must never be NULL (except for ARGPARSE_OPT_END).
+ *
+ *  `callback`:
+ *    function is called when corresponding argument is parsed.
+ *
+ *  `data`:
+ *    associated data. Callbacks can use it like they want.
+ *
+ *  `flags`:
+ *    option flags.
+ */
+struct argparse_option {
+    enum argparse_option_type type;
+    const char short_name;
+    const char *long_name;
+    void *value;
+    const char *help;
+    argparse_callback *callback;
+    intptr_t data;
+    int flags;
+};
+
+/**
+ * argpparse
+ */
+struct argparse {
+    // user supplied
+    const struct argparse_option *options;
+    const char *const *usages;
+    int flags;
+    const char *description;    // a description after usage
+    const char *epilog;         // a description at the end
+    // internal context
+    int argc;
+    const char **argv;
+    const char **out;
+    int cpidx;
+    const char *optvalue;       // current option value
+};
+
+// built-in callbacks
+int argparse_help_cb(struct argparse *self,
+                     const struct argparse_option *option);
+
+// built-in option macros
+#define OPT_END()        { ARGPARSE_OPT_END, 0, NULL, NULL, 0, NULL, 0, 0 }
+#define OPT_BOOLEAN(...) { ARGPARSE_OPT_BOOLEAN, __VA_ARGS__ }
+#define OPT_BIT(...)     { ARGPARSE_OPT_BIT, __VA_ARGS__ }
+#define OPT_INTEGER(...) { ARGPARSE_OPT_INTEGER, __VA_ARGS__ }
+#define OPT_FLOAT(...)   { ARGPARSE_OPT_FLOAT, __VA_ARGS__ }
+#define OPT_STRING(...)  { ARGPARSE_OPT_STRING, __VA_ARGS__ }
+#define OPT_GROUP(h)     { ARGPARSE_OPT_GROUP, 0, NULL, NULL, h, NULL, 0, 0 }
+#define OPT_HELP()       OPT_BOOLEAN('h', "help", NULL,                 \
+                                     "show this help message and exit", \
+                                     argparse_help_cb, 0, 0)
+
+int argparse_init(struct argparse *self, struct argparse_option *options,
+                  const char *const *usages, int flags);
+void argparse_describe(struct argparse *self, const char *description,
+                       const char *epilog);
+int argparse_parse(struct argparse *self, int argc, const char **argv);
+void argparse_usage(struct argparse *self);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif