diff --git a/include/cx.h b/include/cx.h
index c329911..a39f90e 100644
--- a/include/cx.h
+++ b/include/cx.h
@@ -33,6 +33,7 @@ typedef struct _cx_gl_ctx {
     ModelRegistry *mr;
     GLuint *VertexArrayIDs;
     void (*free)(void *self);
+    uint8_t master_lock;
     size_t VertexArray_count;
     size_t VertexArray_size;
     GLuint *programIDs;
@@ -45,6 +46,7 @@ typedef struct _cx_nn_ctx {
     float *input_buffer;
     float *output_buffer;
     void (*free)(void *self);
+    uint8_t master_lock;
 } CX_NN_CTX;
 
 typedef struct _cx_ctx {
diff --git a/src/cx.c b/src/cx.c
index 20a42e8..bd452ab 100644
--- a/src/cx.c
+++ b/src/cx.c
@@ -230,7 +230,10 @@ cx_glrun(CX_GL_CTX *ctx) {
     glfwGetCursorPos(ctx->window, &xpos, &ypos);
 
     do {
-        cx_glrender(ctx->window, ctx->programIDs[0], ctx->mr);
+        // Skip render step if context is locked.
+        if (!ctx->master_lock) {
+            cx_glrender(ctx->window, ctx->programIDs[0], ctx->mr);
+        }
         usleep(1000000/60);
         // Check if the ESC key was pressed or the window was closed
     } while(glfwGetKey(ctx->window, GLFW_KEY_ESCAPE) != GLFW_PRESS
@@ -287,14 +290,18 @@ cx_run(CX_Context *ctx) {
 
     // Establish a model registry
     ctx->gl_ctx->mr = modelRegistry_new();
+    ctx->gl_ctx->master_lock = 1;
+
+    tg[0] = cx_threadGroup_new(&cx_glthread, ctx->gl_ctx);
 
     tg[1] = cx_threadGroup_new(&cx_nnthread, ctx->nn_ctx);
 
     pthread_join(tg[1]->group_manager->thread, NULL);
 
+    ctx->gl_ctx->master_lock = 0;
+
     neural_getMesh(ctx->nn_ctx->nn, ctx->gl_ctx->mr);
 
-    tg[0] = cx_threadGroup_new(&cx_glthread, ctx->gl_ctx);
 
     pthread_join(tg[0]->group_manager->thread, NULL);