diff --git a/src/rendering/twn_draw.c b/src/rendering/twn_draw.c
index cf7af86..0712206 100644
--- a/src/rendering/twn_draw.c
+++ b/src/rendering/twn_draw.c
@@ -329,6 +329,7 @@ static void render_2d(void) {
                 break;
             case PRIMITIVE_2D_LINES:
                 render_lines(&invocation.primitive->line);
+                stbds_arrfreef(invocation.primitive->line.vertices);
                 break;
             case PRIMITIVE_2D_TEXT:
             default:
diff --git a/src/rendering/twn_draw_c.h b/src/rendering/twn_draw_c.h
index 9ffc99f..988012a 100644
--- a/src/rendering/twn_draw_c.h
+++ b/src/rendering/twn_draw_c.h
@@ -322,7 +322,7 @@ IndexBuffer get_circle_element_buffer(void);
 
 void render_circle(const CirclePrimitive *circle);
 
-void render_lines(LinePrimitive *line);
+void render_lines(const LinePrimitive *line);
 
 void render_rectangle(const RectPrimitive *rectangle);
 
diff --git a/src/rendering/twn_lines.c b/src/rendering/twn_lines.c
index c5e282b..08eed66 100644
--- a/src/rendering/twn_lines.c
+++ b/src/rendering/twn_lines.c
@@ -46,7 +46,7 @@ void draw_line(Vec2 start,
 }
 
 
-void render_lines(LinePrimitive *line) {
+void render_lines(LinePrimitive const *line) {
     DeferredCommandDraw command = {0};
 
     VertexBuffer buffer = get_scratch_vertex_array();
@@ -68,7 +68,7 @@ void render_lines(LinePrimitive *line) {
         .buffer = buffer
     };
 
-    command.primitive_count = arrlenu(line->vertices);
+    command.primitive_count = (uint32_t)arrlenu(line->vertices);
 
     command.geometry_mode = DEFERRED_COMMAND_DRAW_GEOMETRY_MODE_LINES;
     command.pipeline = PIPELINE_2D;
@@ -81,7 +81,5 @@ void render_lines(LinePrimitive *line) {
         .draw = command
     };
 
-    /* TODO: should it be deleted here? */
-    arrfree(line->vertices);
     arrpush(deferred_commands, final_command);
 }
diff --git a/src/twn_util.c b/src/twn_util.c
index 40d88c2..d711d95 100644
--- a/src/twn_util.c
+++ b/src/twn_util.c
@@ -181,13 +181,10 @@ bool file_exists(const char *path) {
 void textures_dump_atlases(void) {
     PHYSFS_mkdir("/dump");
 
-    /* TODO: png instead of bmp */
-    const char string_template[] = "/dump/atlas%zd.bmp";
-
     size_t i = 0;
     for (; i < arrlenu(ctx.texture_cache.atlas_surfaces); ++i) {
         char *buf = NULL;
-        SDL_asprintf(&buf, string_template, i);
+        SDL_asprintf(&buf, "/dump/atlas%zd.bmp", (ssize_t)i);
 
         SDL_RWops *handle = PHYSFSRWOPS_openWrite(buf);
 
diff --git a/src/twn_workers.c b/src/twn_workers.c
index 3a0c010..963d388 100644
--- a/src/twn_workers.c
+++ b/src/twn_workers.c
@@ -1,9 +1,8 @@
-#include "twn_util.h"
 #include "twn_workers_c.h"
 #include "rendering/twn_draw_c.h"
 
 #ifndef __EMSCRIPTEN__
-SDL_sem *workers_job_semaphore;
+static SDL_sem *workers_job_semaphore;
 
 static SDL_mutex *workers_mutex;
 static SDL_sem *workers_exit_semaphore; /* should come to count of `workers_pool_size` */