anchor model and data paths to repo root via __file__

src/streamlit_app.py

@@ -1,7 +1,14 @@
+import os
 import streamlit as st
 import numpy as np
 import pandas as pd
 
+# Paths anchored to the repo root regardless of working directory
+_SRC_DIR = os.path.dirname(os.path.abspath(__file__))   # /app/src
+_REPO_ROOT = os.path.dirname(_SRC_DIR)                  # /app
+_MODEL_PATH = os.path.join(_REPO_ROOT, "model.keras")
+_SAMPLES_PATH = os.path.join(_REPO_ROOT, "data", "samples.csv")
+
 # ── Constants ──────────────────────────────────────────────────────────────
 
 LABEL_MAP = {
@@ -26,11 +33,14 @@ EXPLANATIONS = {
 
 @st.cache_resource
 def load_model():
+    if not os.path.exists(_MODEL_PATH):
+        root_files = os.listdir(_REPO_ROOT)
+        return None, f"error: model.keras not found at {_MODEL_PATH}. Files in {_REPO_ROOT}: {root_files}"
     try:
         import tensorflow as tf
         from model_def import FeedForwardNetwork
         model = tf.keras.models.load_model(
-            "model.keras",
+            _MODEL_PATH,
             custom_objects={"FeedForwardNetwork": FeedForwardNetwork},
         )
         return model, "ready"
@@ -92,7 +102,7 @@ with tab1:
     )
 
     try:
-        samples_df = pd.read_csv("data/samples.csv")
+        samples_df = pd.read_csv(_SAMPLES_PATH)
         feature_cols = [
             c for c in samples_df.columns
             if c not in ["Activity", "subject"]