diff --git a/include/sway/commands.h b/include/sway/commands.h
index 41858ccc..f83907b2 100644
--- a/include/sway/commands.h
+++ b/include/sway/commands.h
@@ -150,6 +150,7 @@ sway_cmd cmd_splitt;
 sway_cmd cmd_splitv;
 sway_cmd cmd_sticky;
 sway_cmd cmd_swaybg_command;
+sway_cmd cmd_swaynag_command;
 sway_cmd cmd_swap;
 sway_cmd cmd_title_format;
 sway_cmd cmd_unmark;
diff --git a/include/sway/config.h b/include/sway/config.h
index 909b6827..632aca14 100644
--- a/include/sway/config.h
+++ b/include/sway/config.h
@@ -7,6 +7,7 @@
 #include <wlr/types/wlr_box.h>
 #include <xkbcommon/xkbcommon.h>
 #include "list.h"
+#include "swaynag.h"
 #include "tree/layout.h"
 #include "tree/container.h"
 #include "wlr-layer-shell-unstable-v1-protocol.h"
@@ -308,6 +309,8 @@ enum focus_wrapping_mode {
  * The configuration struct. The result of loading a config file.
  */
 struct sway_config {
+	char *swaynag_command;
+	struct swaynag_instance swaynag_config_errors;
 	list_t *symbols;
 	list_t *modes;
 	list_t *bars;
@@ -345,6 +348,7 @@ struct sway_config {
 	bool failed;
 	bool reloading;
 	bool reading;
+	bool validating;
 	bool auto_back_and_forth;
 	bool show_marks;
 
@@ -403,17 +407,19 @@ struct sway_config {
  * Loads the main config from the given path. is_active should be true when
  * reloading the config.
  */
-bool load_main_config(const char *path, bool is_active);
+bool load_main_config(const char *path, bool is_active, bool validating);
 
 /**
  * Loads an included config. Can only be used after load_main_config.
  */
-bool load_include_configs(const char *path, struct sway_config *config);
+bool load_include_configs(const char *path, struct sway_config *config,
+		struct swaynag_instance *swaynag);
 
 /**
  * Reads the config from the given FILE.
  */
-bool read_config(FILE *file, struct sway_config *config);
+bool read_config(FILE *file, struct sway_config *config,
+		struct swaynag_instance *swaynag);
 
 /**
  * Free config struct
diff --git a/include/sway/swaynag.h b/include/sway/swaynag.h
new file mode 100644
index 00000000..5a178739
--- /dev/null
+++ b/include/sway/swaynag.h
@@ -0,0 +1,29 @@
+#ifndef _SWAY_SWAYNAG_H
+#define _SWAY_SWAYNAG_H
+
+struct swaynag_instance {
+	const char *args;
+	pid_t pid;
+	int fd[2];
+	bool detailed;
+};
+
+// Spawn swaynag. If swaynag->detailed, then swaynag->fd[1] will left open
+// so it can be written to. Call swaynag_show when done writing. This will
+// be automatically called by swaynag_log if the instance is not spawned and
+// swaynag->detailed is true.
+bool swaynag_spawn(const char *swaynag_command,
+		struct swaynag_instance *swaynag);
+
+// Kill the swaynag instance
+void swaynag_kill(struct swaynag_instance *swaynag);
+
+// Write a log message to swaynag->fd[1]. This will fail when swaynag->detailed
+// is false.
+void swaynag_log(const char *swaynag_command, struct swaynag_instance *swaynag,
+		const char *fmt, ...);
+
+// If swaynag->detailed, close swaynag->fd[1] so swaynag displays
+void swaynag_show(struct swaynag_instance *swaynag);
+
+#endif
diff --git a/sway/commands.c b/sway/commands.c
index fdae1961..364c26da 100644
--- a/sway/commands.c
+++ b/sway/commands.c
@@ -132,6 +132,7 @@ static struct cmd_handler handlers[] = {
 static struct cmd_handler config_handlers[] = {
 	{ "default_orientation", cmd_default_orientation },
 	{ "swaybg_command", cmd_swaybg_command },
+	{ "swaynag_command", cmd_swaynag_command },
 	{ "workspace_layout", cmd_workspace_layout },
 };
 
diff --git a/sway/commands/include.c b/sway/commands/include.c
index 1ba9a10d..61f383bb 100644
--- a/sway/commands/include.c
+++ b/sway/commands/include.c
@@ -7,8 +7,10 @@ struct cmd_results *cmd_include(int argc, char **argv) {
 		return error;
 	}
 
-	if (!load_include_configs(argv[0], config)) {
-		return cmd_results_new(CMD_INVALID, "include", "Failed to include sub configuration file: %s", argv[0]);
+	if (!load_include_configs(argv[0], config,
+				&config->swaynag_config_errors)) {
+		return cmd_results_new(CMD_INVALID, "include",
+				"Failed to include sub configuration file: %s", argv[0]);
 	}
 
 	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
diff --git a/sway/commands/reload.c b/sway/commands/reload.c
index 5c1b19b4..f8ca374d 100644
--- a/sway/commands/reload.c
+++ b/sway/commands/reload.c
@@ -19,8 +19,9 @@ struct cmd_results *cmd_reload(int argc, char **argv) {
 		list_add(bar_ids, strdup(bar->id));
 	}
 
-	if (!load_main_config(config->current_config_path, true)) {
-		return cmd_results_new(CMD_FAILURE, "reload", "Error(s) reloading config.");
+	if (!load_main_config(config->current_config_path, true, false)) {
+		return cmd_results_new(CMD_FAILURE, "reload",
+				"Error(s) reloading config.");
 	}
 	ipc_event_workspace(NULL, NULL, "reload");
 
@@ -42,5 +43,6 @@ struct cmd_results *cmd_reload(int argc, char **argv) {
 	list_free(bar_ids);
 
 	arrange_windows(&root_container);
+
 	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
 }
diff --git a/sway/commands/swaynag_command.c b/sway/commands/swaynag_command.c
new file mode 100644
index 00000000..c57a80a6
--- /dev/null
+++ b/sway/commands/swaynag_command.c
@@ -0,0 +1,20 @@
+#include <string.h>
+#include "sway/commands.h"
+#include "log.h"
+#include "stringop.h"
+
+struct cmd_results *cmd_swaynag_command(int argc, char **argv) {
+	struct cmd_results *error = NULL;
+	if ((error = checkarg(argc, "swaynag_command", EXPECTED_AT_LEAST, 1))) {
+		return error;
+	}
+
+	if (config->swaynag_command) {
+		free(config->swaynag_command);
+	}
+	config->swaynag_command = join_args(argv, argc);
+	wlr_log(WLR_DEBUG, "Using custom swaynag command: %s",
+			config->swaynag_command);
+
+	return cmd_results_new(CMD_SUCCESS, NULL, NULL);
+}
diff --git a/sway/config.c b/sway/config.c
index 2afffab1..c1ec77f9 100644
--- a/sway/config.c
+++ b/sway/config.c
@@ -25,6 +25,7 @@
 #include "sway/commands.h"
 #include "sway/config.h"
 #include "sway/criteria.h"
+#include "sway/swaynag.h"
 #include "sway/tree/arrange.h"
 #include "sway/tree/layout.h"
 #include "sway/tree/workspace.h"
@@ -72,6 +73,8 @@ void free_config(struct sway_config *config) {
 
 	memset(&config->handler_context, 0, sizeof(config->handler_context));
 
+	free(config->swaynag_command);
+
 	// TODO: handle all currently unhandled lists as we add implementations
 	if (config->symbols) {
 		for (int i = 0; i < config->symbols->length; ++i) {
@@ -158,6 +161,17 @@ static void set_color(float dest[static 4], uint32_t color) {
 }
 
 static void config_defaults(struct sway_config *config) {
+	config->swaynag_command = strdup("swaynag");
+	config->swaynag_config_errors = (struct swaynag_instance){
+		.args = "--type error "
+			"--message 'There are errors in your config file' "
+			"--detailed-message "
+			"--button 'Exit sway' 'swaymsg exit' "
+			"--button 'Reload sway' 'swaymsg reload'",
+		.pid = -1,
+		.detailed = true,
+	};
+
 	if (!(config->symbols = create_list())) goto cleanup;
 	if (!(config->modes = create_list())) goto cleanup;
 	if (!(config->bars = create_list())) goto cleanup;
@@ -204,6 +218,7 @@ static void config_defaults(struct sway_config *config) {
 	config->focus_follows_mouse = true;
 	config->mouse_warping = true;
 	config->focus_wrapping = WRAP_YES;
+	config->validating = false;
 	config->reloading = false;
 	config->active = false;
 	config->failed = false;
@@ -319,7 +334,8 @@ static char *get_config_path(void) {
 	return NULL; // Not reached
 }
 
-static bool load_config(const char *path, struct sway_config *config) {
+static bool load_config(const char *path, struct sway_config *config,
+		struct swaynag_instance *swaynag) {
 	if (path == NULL) {
 		wlr_log(WLR_ERROR, "Unable to find a config file!");
 		return false;
@@ -338,7 +354,7 @@ static bool load_config(const char *path, struct sway_config *config) {
 		return false;
 	}
 
-	bool config_load_success = read_config(f, config);
+	bool config_load_success = read_config(f, config, swaynag);
 	fclose(f);
 
 	if (!config_load_success) {
@@ -348,7 +364,7 @@ static bool load_config(const char *path, struct sway_config *config) {
 	return true;
 }
 
-bool load_main_config(const char *file, bool is_active) {
+bool load_main_config(const char *file, bool is_active, bool validating) {
 	char *path;
 	if (file != NULL) {
 		path = strdup(file);
@@ -363,10 +379,17 @@ bool load_main_config(const char *file, bool is_active) {
 	}
 
 	config_defaults(config);
+	config->validating = validating;
 	if (is_active) {
 		wlr_log(WLR_DEBUG, "Performing configuration file reload");
 		config->reloading = true;
 		config->active = true;
+
+		swaynag_kill(&old_config->swaynag_config_errors);
+		memcpy(&config->swaynag_config_errors,
+				&old_config->swaynag_config_errors,
+				sizeof(struct swaynag_instance));
+
 		create_default_output_configs();
 	}
 
@@ -423,13 +446,17 @@ bool load_main_config(const char *file, bool is_active) {
 	}
 	*/
 
-	success = success && load_config(path, config);
+	success = success && load_config(path, config,
+			&config->swaynag_config_errors);
 
 	if (is_active) {
 		for (int i = 0; i < config->output_configs->length; i++) {
 			apply_output_config_to_outputs(config->output_configs->items[i]);
 		}
 		config->reloading = false;
+		if (config->swaynag_config_errors.pid > 0) {
+			swaynag_show(&config->swaynag_config_errors);
+		}
 	}
 
 	if (old_config) {
@@ -441,7 +468,7 @@ bool load_main_config(const char *file, bool is_active) {
 }
 
 static bool load_include_config(const char *path, const char *parent_dir,
-		struct sway_config *config) {
+		struct sway_config *config, struct swaynag_instance *swaynag) {
 	// save parent config
 	const char *parent_config = config->current_config_path;
 
@@ -485,7 +512,7 @@ static bool load_include_config(const char *path, const char *parent_dir,
 	list_add(config->config_chain, real_path);
 	int index = config->config_chain->length - 1;
 
-	if (!load_config(real_path, config)) {
+	if (!load_config(real_path, config, swaynag)) {
 		free(real_path);
 		config->current_config_path = parent_config;
 		list_del(config->config_chain, index);
@@ -497,7 +524,8 @@ static bool load_include_config(const char *path, const char *parent_dir,
 	return true;
 }
 
-bool load_include_configs(const char *path, struct sway_config *config) {
+bool load_include_configs(const char *path, struct sway_config *config,
+		struct swaynag_instance *swaynag) {
 	char *wd = getcwd(NULL, 0);
 	char *parent_path = strdup(config->current_config_path);
 	const char *parent_dir = dirname(parent_path);
@@ -519,7 +547,7 @@ bool load_include_configs(const char *path, struct sway_config *config) {
 	char **w = p.we_wordv;
 	size_t i;
 	for (i = 0; i < p.we_wordc; ++i) {
-		load_include_config(w[i], parent_dir, config);
+		load_include_config(w[i], parent_dir, config, swaynag);
 	}
 	free(parent_path);
 	wordfree(&p);
@@ -575,7 +603,8 @@ static char *expand_line(const char *block, const char *line, bool add_brace) {
 	return expanded;
 }
 
-bool read_config(FILE *file, struct sway_config *config) {
+bool read_config(FILE *file, struct sway_config *config,
+		struct swaynag_instance *swaynag) {
 	bool reading_main_config = false;
 	char *this_config = NULL;
 	size_t config_size = 0;
@@ -665,6 +694,11 @@ bool read_config(FILE *file, struct sway_config *config) {
 		case CMD_INVALID:
 			wlr_log(WLR_ERROR, "Error on line %i '%s': %s (%s)", line_number,
 				line, res->error, config->current_config_path);
+			if (!config->validating) {
+				swaynag_log(config->swaynag_command, swaynag,
+					"Error on line %i (%s) '%s': %s", line_number,
+					config->current_config_path, line, res->error);
+			}
 			success = false;
 			break;
 
diff --git a/sway/main.c b/sway/main.c
index 477ffa5a..c02caf42 100644
--- a/sway/main.c
+++ b/sway/main.c
@@ -22,6 +22,7 @@
 #include "sway/debug.h"
 #include "sway/desktop/transaction.h"
 #include "sway/server.h"
+#include "sway/swaynag.h"
 #include "sway/tree/layout.h"
 #include "sway/ipc-server.h"
 #include "ipc-client.h"
@@ -416,11 +417,12 @@ int main(int argc, char **argv) {
 	log_env();
 
 	if (validate) {
-		bool valid = load_main_config(config_path, false);
+		bool valid = load_main_config(config_path, false, true);
 		return valid ? 0 : 1;
 	}
 
-	if (!load_main_config(config_path, false)) {
+	setenv("WAYLAND_DISPLAY", server.socket, true);
+	if (!load_main_config(config_path, false, false)) {
 		sway_terminate(EXIT_FAILURE);
 	}
 
@@ -430,7 +432,6 @@ int main(int argc, char **argv) {
 
 	security_sanity_check();
 
-	setenv("WAYLAND_DISPLAY", server.socket, true);
 	if (!terminate_request) {
 		if (!server_start_backend(&server)) {
 			sway_terminate(EXIT_FAILURE);
@@ -452,6 +453,10 @@ int main(int argc, char **argv) {
 	}
 	transaction_commit_dirty();
 
+	if (config->swaynag_config_errors.pid > 0) {
+		swaynag_show(&config->swaynag_config_errors);
+	}
+
 	if (!terminate_request) {
 		server_run(&server);
 	}
diff --git a/sway/meson.build b/sway/meson.build
index a9503c3b..17406f6b 100644
--- a/sway/meson.build
+++ b/sway/meson.build
@@ -9,6 +9,7 @@ sway_sources = files(
 	'ipc-server.c',
 	'scratchpad.c',
 	'security.c',
+	'swaynag.c',
 
 	'desktop/desktop.c',
 	'desktop/idle_inhibit_v1.c',
@@ -78,6 +79,7 @@ sway_sources = files(
 	'commands/split.c',
 	'commands/sticky.c',
 	'commands/swaybg_command.c',
+	'commands/swaynag_command.c',
 	'commands/swap.c',
 	'commands/title_format.c',
 	'commands/unmark.c',
diff --git a/sway/sway.5.scd b/sway/sway.5.scd
index d369d7b6..82df38e3 100644
--- a/sway/sway.5.scd
+++ b/sway/sway.5.scd
@@ -59,6 +59,13 @@ The following commands may only be used in the configuration file.
 	Executes custom background _command_. Default is _swaybg_. Refer to
 	*output* below for more information.
 
+*swaynag\_command* <command>
+	Executes custom command for _swaynag_. Default is _swaynag_. Additional
+	arguments may be appended to the end. This should only be used to either
+	direct sway to call swaynag from a custom path or to provide additional
+	arguments. This should be placed at the top of the config for the best
+	results.
+
 The following commands cannot be used directly in the configuration file.
 They are expected to be used with *bindsym* or at runtime through *swaymsg*(1).
 
diff --git a/sway/swaynag.c b/sway/swaynag.c
new file mode 100644
index 00000000..f5370807
--- /dev/null
+++ b/sway/swaynag.c
@@ -0,0 +1,94 @@
+#include <fcntl.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <unistd.h>
+#include "log.h"
+#include "sway/swaynag.h"
+
+bool swaynag_spawn(const char *swaynag_command,
+		struct swaynag_instance *swaynag) {
+	if (swaynag->detailed) {
+		if (pipe(swaynag->fd) != 0) {
+			wlr_log(WLR_ERROR, "Failed to create pipe for swaynag");
+			return false;
+		}
+		fcntl(swaynag->fd[1], F_SETFD, FD_CLOEXEC);
+	}
+
+	pid_t pid;
+	if ((pid = fork()) == 0) {
+		if (swaynag->detailed) {
+			close(swaynag->fd[1]);
+			dup2(swaynag->fd[0], STDIN_FILENO);
+			close(swaynag->fd[0]);
+		}
+
+		size_t length = strlen(swaynag_command) + strlen(swaynag->args) + 2;
+		char *cmd = malloc(length);
+		snprintf(cmd, length, "%s %s", swaynag_command, swaynag->args);
+		execl("/bin/sh", "/bin/sh", "-c", cmd, NULL);
+		_exit(0);
+	} else if (pid < 0) {
+		wlr_log(WLR_ERROR, "Failed to create fork for swaynag");
+		if (swaynag->detailed) {
+			close(swaynag->fd[0]);
+			close(swaynag->fd[1]);
+		}
+		return false;
+	}
+
+	if (swaynag->detailed) {
+		close(swaynag->fd[0]);
+	}
+	swaynag->pid = pid;
+	return true;
+}
+
+
+void swaynag_kill(struct swaynag_instance *swaynag) {
+	if (swaynag->pid > 0) {
+		kill(swaynag->pid, SIGTERM);
+		swaynag->pid = -1;
+	}
+}
+
+void swaynag_log(const char *swaynag_command, struct swaynag_instance *swaynag,
+		const char *fmt, ...) {
+	if (!swaynag->detailed) {
+		wlr_log(WLR_ERROR, "Attempting to write to non-detailed swaynag inst");
+		return;
+	}
+
+	if (swaynag->pid <= 0 && !swaynag_spawn(swaynag_command, swaynag)) {
+		return;
+	}
+
+	va_list args;
+	va_start(args, fmt);
+	size_t length = vsnprintf(NULL, 0, fmt, args) + 1;
+	va_end(args);
+
+	char *temp = malloc(length + 1);
+	if (!temp) {
+		wlr_log(WLR_ERROR, "Failed to allocate buffer for swaynag log entry.");
+		return;
+	}
+
+	va_start(args, fmt);
+	vsnprintf(temp, length, fmt, args);
+	va_end(args);
+
+	write(swaynag->fd[1], temp, length);
+
+	free(temp);
+}
+
+void swaynag_show(struct swaynag_instance *swaynag) {
+	if (swaynag->detailed && swaynag->pid > 0) {
+		close(swaynag->fd[1]);
+	}
+}
+