diff --git a/Makefile.dev b/Makefile.dev
index d0baa95..0c1d5a4 100644
--- a/Makefile.dev
+++ b/Makefile.dev
@@ -12,7 +12,7 @@ build:
 	gcc -Wall -Wextra src/*.c src/*.h -lglfw -lGL -lm -Iinclude -ldl -o build/$(TARGET)
 
 run: build
-	./build/forge
+	./build/forge --frag=./shaders/frag.glsl
 
 .PHONY: install
 install: build
diff --git a/README.md b/README.md
index e9a4e60..a03b8c7 100644
--- a/README.md
+++ b/README.md
@@ -56,6 +56,7 @@ options:
   --help             show this help message and exit
   -v, --version      print version
   -s, --screen       output screen number (default: primary)
+  -f, --frag         fragment shader path (default: TODO)
 ```
 
 ## Release guide
@@ -90,20 +91,31 @@ make -f Makefile.dev release-arch
   - [ ] Handle compilation errors
   - [x] Minimal working fragment sample
   - [x] Hot-reload fragment shader
-  - [ ] Specify fragment shader path
+  - [x] Specify fragment shader path
   - [x] Force fullscreen
   - [x] Select screen as argument / config
+  - [ ] Clean code
+- [ ] Multi-stage shaders
+  - [ ] Test 2 stages with render to texture
+  - [ ] 2 in 2 fx 1 mix 1 fx layout
+  - [ ] Include fragments with special directive
+  - [ ] 16 input + 16 fx definition and selection (with param)
+  - [ ] Feedback texture
+  - [ ] Clean code
 - [ ] Midi
   - [ ] Read Midi events
   - [ ] Read midi mapping config file
   - [ ] Write Midi events
-- [ ] MVP
-  - [ ] Add required libraries in target build
-  - [ ] Include fragments with special directive
-  - [ ] Source mixing
   - [ ] Save midi state
-- [ ] Advanced
-  - [ ] Video input
-  - [ ] Feedback input
   - [ ] Tap-tempo feature
-  - [ ] Monitor screen feature (other window)
\ No newline at end of file
+  - [ ] Clean code
+- [ ] Video input
+  - [ ] Fixed camera video
+  - [ ] Video mapping config file
+  - [ ] Clean code
+- [ ] Monitor screen
+  - [ ] 2nd window
+  - [ ] Use buffers as panels (INA A FXA / DEBUG A+B FXA+B / INB B FXB)
+  - [ ] Clean code
+- [ ] Packaging & install
+  - [ ] Clone "shaders" and config in system path at setup
\ No newline at end of file
diff --git a/src/args.c b/src/args.c
index e7cbd77..e903fce 100644
--- a/src/args.c
+++ b/src/args.c
@@ -7,18 +7,19 @@
 #include "config.h"
 
 void print_help(int status_code) {
-  puts(PACKAGE
-       " " VERSION "\n\n"
-       "usage: " PACKAGE " "
-       "[--help] "
-       "[-v] "
-       "[-s=SCREEN] "
-       "\n\n"
-       "Fusion Of Real-time Generative Effects.\n\n"
-       "options:\n"
-       "  --help             show this help message and exit\n"
-       "  -v, --version      print version\n"
-       "  -s, --screen       output screen number (default: primary)\n");
+  puts(PACKAGE " " VERSION "\n\n"
+               "usage: " PACKAGE " "
+               "[--help] "
+               "[-v] "
+               "[-s=SCREEN] "
+               "[-f=FRAG_PATH] "
+               "\n\n"
+               "Fusion Of Real-time Generative Effects.\n\n"
+               "options:\n"
+               "  --help             show this help message and exit\n"
+               "  -v, --version      print version\n"
+               "  -s, --screen       output screen number (default: primary)\n"
+               "  -f, --frag         fragment shader path (default: TODO)\n");
   exit(status_code);
 }
 
@@ -67,9 +68,7 @@ unsigned char parse_uchar(char *arg, char *value) {
 }
 
 Parameters parse_args(int argc, char **argv) {
-  Parameters params;
-
-  params.screen = 0;
+  Parameters params = {0, 0};
 
   int i;
   char *arg;
@@ -84,10 +83,17 @@ Parameters parse_args(int argc, char **argv) {
       exit(EXIT_SUCCESS);
     } else if (is_arg(arg, "-s") || is_arg(arg, "--screen")) {
       params.screen = parse_uchar(arg, value);
+    } else if (is_arg(arg, "-f") || is_arg(arg, "--frag")) {
+      params.frag_path = value;
     } else {
       invalid_arg(arg);
     }
   }
 
+  if (params.frag_path == 0) {
+    fprintf(stderr, "required argument -f/--frag\n\n");
+    exit(EXIT_FAILURE);
+  }
+
   return params;
 }
\ No newline at end of file
diff --git a/src/forge.c b/src/forge.c
index 811d0bf..5e3f427 100644
--- a/src/forge.c
+++ b/src/forge.c
@@ -181,7 +181,7 @@ void loop(GLFWwindow *window, ShaderProgram program) {
 void forge_run(Parameters params) {
   GLFWwindow *window;
 
-  File fragment_shader = read_file("shaders/tmp.glsl");
+  File fragment_shader = read_file(params.frag_path);
 
   if (fragment_shader.error) {
     fprintf(stderr, "Cannot read file\n");
diff --git a/src/types.h b/src/types.h
index f5a1a61..96ee2d0 100644
--- a/src/types.h
+++ b/src/types.h
@@ -9,6 +9,7 @@
 
 typedef struct Parameters {
   unsigned char screen;
+  char *frag_path;
 } Parameters;
 
 typedef struct Vertex {