diff --git a/include/env.h b/include/env.h
new file mode 100644
index 000000000..16a811a4c
--- /dev/null
+++ b/include/env.h
@@ -0,0 +1,28 @@
+#ifndef _SWAY_ENV_H
+#define _SWAY_ENV_H
+
+/**
+ * Deallocates an environment array created by
+ * sway_env_get_envp or sway_env_setenv.
+ */
+void env_destroy(char **envp);
+
+/**
+ * Gets a newly-allocated environment array pointer
+ * from the global environment.
+ */
+char **env_create();
+
+/**
+ * Sets or overwrites an environment variable in the given environment.
+ * Setting a new variable will reallocate the entire array.
+ */
+char **env_setenv(char **envp, char *name, char *value);
+
+/**
+ * Unsets an environment variable in the given environment.
+ * If successful, this will reallocate the entire array.
+ */
+char **env_unsetenv(char **envp, char *name);
+
+#endif
diff --git a/include/sway/commands.h b/include/sway/commands.h
index 5210d3ba7..e933b3728 100644
--- a/include/sway/commands.h
+++ b/include/sway/commands.h
@@ -125,6 +125,8 @@ sway_cmd cmd_create_output;
 sway_cmd cmd_default_border;
 sway_cmd cmd_default_floating_border;
 sway_cmd cmd_default_orientation;
+sway_cmd cmd_env;
+sway_cmd cmd_env_unset;
 sway_cmd cmd_exec;
 sway_cmd cmd_exec_always;
 sway_cmd cmd_exit;
diff --git a/sway/commands.c b/sway/commands.c
index c2c12ee65..e19f86867 100644
--- a/sway/commands.c
+++ b/sway/commands.c
@@ -57,6 +57,8 @@ static const struct cmd_handler handlers[] = {
 	{ "client.urgent", cmd_client_urgent },
 	{ "default_border", cmd_default_border },
 	{ "default_floating_border", cmd_default_floating_border },
+	{ "env", cmd_env },
+	{ "env_unset", cmd_env_unset },
 	{ "exec", cmd_exec },
 	{ "exec_always", cmd_exec_always },
 	{ "floating_maximum_size", cmd_floating_maximum_size },
diff --git a/sway/commands/env.c b/sway/commands/env.c
new file mode 100644
index 000000000..aba4e33b2
--- /dev/null
+++ b/sway/commands/env.c
@@ -0,0 +1,28 @@
+#define _POSIX_C_SOURCE 200809L
+#include <stdlib.h>
+#include "sway/commands.h"
+#include "env.h"
+
+extern char **child_envp;
+
+struct cmd_results *cmd_env(int argc, char **argv) {
+	struct cmd_results *error = NULL;
+	if ((error = checkarg(argc, "env", EXPECTED_EQUAL_TO, 2))) {
+		return error;
+	}
+
+	child_envp = env_setenv(child_envp, argv[0], argv[1]);
+
+	return cmd_results_new(CMD_SUCCESS, NULL);
+}
+
+struct cmd_results *cmd_env_unset(int argc, char **argv) {
+	struct cmd_results *error = NULL;
+	if ((error = checkarg(argc, "env_unset", EXPECTED_EQUAL_TO, 1))) {
+		return error;
+	}
+
+	child_envp = env_unsetenv(child_envp, argv[0]);
+
+	return cmd_results_new(CMD_SUCCESS, NULL);
+}
diff --git a/sway/commands/exec_always.c b/sway/commands/exec_always.c
index 8bc1048cd..502beeb30 100644
--- a/sway/commands/exec_always.c
+++ b/sway/commands/exec_always.c
@@ -14,6 +14,8 @@
 #include "log.h"
 #include "stringop.h"
 
+extern char** child_envp;
+
 struct cmd_results *cmd_exec_validate(int argc, char **argv) {
 	struct cmd_results *error = NULL;
 	if ((error = checkarg(argc, argv[-1], EXPECTED_AT_LEAST, 1))) {
@@ -81,7 +83,7 @@ struct cmd_results *cmd_exec_process(int argc, char **argv) {
 			if (ctx && !no_startup_id) {
 				export_startup_id(ctx);
 			}
-			execlp("sh", "sh", "-c", cmd, (void *)NULL);
+			execle("/bin/sh", "sh", "-c", cmd, (void *)NULL, child_envp);
 			sway_log_errno(SWAY_ERROR, "execlp failed");
 			_exit(1);
 		}
diff --git a/sway/env.c b/sway/env.c
new file mode 100644
index 000000000..8c7d63c24
--- /dev/null
+++ b/sway/env.c
@@ -0,0 +1,125 @@
+#define _POSIX_C_SOURCE 200809L
+#include <stdlib.h>
+#include <string.h>
+
+typedef struct {
+	char *ptr;
+	size_t idx;
+} env_info;
+
+extern char **environ;
+
+int env_name_eq(char *env_name, char *cmp) {
+	size_t i = 0;
+	int reached_eq;
+	while (1) {
+		char current_char = env_name[i];
+		char cmp_char = cmp[i];
+
+		int is_eq = current_char == '=';
+		int is_null = current_char == '\0';
+
+		if (is_eq) reached_eq = 1;
+		if (is_null && !reached_eq) return 0;
+		if (is_eq && cmp_char == '\0') return 1;
+		if (is_eq || cmp_char == '\0') return 0;
+		if (current_char != cmp_char) return 0;
+
+		i++;
+	}
+}
+
+env_info env_get(char **envp, char *name) {
+	char *strp;
+	size_t i = 0;
+	while ((strp = envp[i]) != NULL) {
+		if (env_name_eq(strp, name)) return (env_info){strp, i};
+		i++;
+	}
+
+	return (env_info){NULL, 0};
+}
+
+size_t env_len(char **envp) {
+	char *strp;
+	size_t i = 0;
+
+	while ((strp = envp[i]) != NULL) {
+		i++;
+	}
+
+	return i;
+}
+
+char **env_clone(char **envp, size_t reserve, env_info exclude) {
+	size_t elem_count = env_len(envp) + 1 + reserve - (exclude.ptr != NULL);
+	char **new_envp = calloc(elem_count, sizeof(char *));
+
+	char *strp;
+	size_t i = 0;
+	size_t new_i = 0;
+
+	while ((strp = envp[i]) != NULL) {
+		if (exclude.ptr == strp) {
+			i++;
+			continue;
+		}
+		size_t n = strlen(strp) + 1;
+		char *new_strp = malloc(n);
+		memcpy(new_strp, strp, n);
+		new_envp[new_i] = new_strp;
+		i++;
+		new_i++;
+	}
+
+	return new_envp;
+}
+
+void env_destroy(char **envp) {
+	char *strp;
+	size_t i = 0;
+	while ((strp = envp[i]) != NULL) {
+		free(strp);
+		i++;
+	}
+
+	free(envp);
+}
+
+// copy the global environment array into a newly-allocated one
+// you are responsible for deallocating it after use
+char **env_create() { return env_clone(environ, 0, (env_info){NULL, 0}); }
+
+// use env_get_envp() to acquire an envp
+// might clone and deallocate the given envp
+char **env_setenv(char **envp, char *name, char *value) {
+	size_t name_len = strlen(name);
+	size_t value_len = strlen(value);
+	char *newp = malloc(name_len + value_len + 2);
+	memcpy(newp, name, name_len);
+	memcpy(newp + name_len + 1, value, value_len);
+	newp[name_len] = '=';
+	newp[name_len + value_len + 1] = '\0';
+
+	env_info existing = env_get(envp, name);
+	if (existing.ptr != NULL) {
+		free(existing.ptr);
+		envp[existing.idx] = newp;
+		return envp;
+	} else {
+		char **new_envp = env_clone(envp, 1, (env_info){NULL, 0});
+		new_envp[env_len(envp)] = newp;
+		env_destroy(envp);
+		return new_envp;
+	}
+}
+
+char **env_unsetenv(char **envp, char *name) {
+	env_info existing = env_get(envp, name);
+	if (existing.ptr == NULL) // dont do anything if
+		return envp;          // the variable is not set
+
+	char **new_envp = env_clone(envp, 0, existing);
+	env_destroy(envp);
+	return new_envp;
+}
diff --git a/sway/main.c b/sway/main.c
index accffc71f..6150804f1 100644
--- a/sway/main.c
+++ b/sway/main.c
@@ -24,12 +24,14 @@
 #include "log.h"
 #include "stringop.h"
 #include "util.h"
+#include "env.h"
 
 static bool terminate_request = false;
 static int exit_value = 0;
 static struct rlimit original_nofile_rlimit = {0};
 struct sway_server server = {0};
 struct sway_debug debug = {0};
+char **child_envp;
 
 void sway_terminate(int exit_code) {
 	if (!server.wl_display) {
@@ -348,6 +350,8 @@ int main(int argc, char **argv) {
 	ipc_init(&server);
 
 	setenv("WAYLAND_DISPLAY", server.socket, true);
+	// env_get_envp creates a newly-allocated environment buffer
+	child_envp = env_create();
 	if (!load_main_config(config_path, false, false)) {
 		sway_terminate(EXIT_FAILURE);
 		goto shutdown;
@@ -382,6 +386,7 @@ shutdown:
 
 	free(config_path);
 	free_config(config);
+	g_strfreev(child_envp);
 
 	pango_cairo_font_map_set_default(NULL);
 
diff --git a/sway/meson.build b/sway/meson.build
index 8042c89be..75c2410ab 100644
--- a/sway/meson.build
+++ b/sway/meson.build
@@ -3,6 +3,7 @@ sway_sources = files(
 	'config.c',
 	'criteria.c',
 	'decoration.c',
+	'env.c',
 	'ipc-json.c',
 	'ipc-server.c',
 	'lock.c',
@@ -52,6 +53,7 @@ sway_sources = files(
 	'commands/default_border.c',
 	'commands/default_floating_border.c',
 	'commands/default_orientation.c',
+	'commands/env.c',
 	'commands/exit.c',
 	'commands/exec.c',
 	'commands/exec_always.c',