Cache binary download (no force_download); fix indentation

app.py

@@ -117,35 +117,33 @@ def boot_phoenix():
         return
 
     # Phase 2: Download pre-built binary from HF Hub (avoids compilation on Space)
-    _update_boot("build", "Downloading phoenix binary from Hub...")
-    # Always re-download to ensure we get the latest binary
-    if os.path.exists(PHOENIX_BIN):
-        os.unlink(PHOENIX_BIN)
-    try:
-        hf_hub_download(
-            repo_id=MODEL_REPO,
-            filename="phoenix",
-            local_dir=SPACE_DIR,
-            local_dir_use_symlinks=False,
-            force_download=True,
-            force_filename="phoenix",
-        )
-        os.chmod(PHOENIX_BIN, 0o755)
-    except Exception as e:
-        # Fallback: compile from source
-        _update_boot("build", f"Binary download failed, compiling... ({e})")
-        src_path = os.path.join(SPACE_DIR, "phoenix_brain.c")
-        if os.path.exists(src_path):
-            cc = os.environ.get("CC", "cc")
-            cmd = [cc, "-O3", "-std=c11", "-march=native", "-fopenmp",
-                   src_path, "-o", PHOENIX_BIN, "-lm"]
-            result = subprocess.run(cmd, capture_output=True, text=True, timeout=120)
-            if result.returncode != 0:
-                _update_boot("build", f"Build FAILED: {result.stderr[:500]}")
+    _update_boot("build", "Checking for phoenix binary...")
+    # Only download if binary doesn't exist (cached after first download)
+    if not os.path.exists(PHOENIX_BIN):
+        try:
+            _update_boot("build", "Downloading phoenix binary from Hub...")
+            hf_hub_download(
+                repo_id=MODEL_REPO,
+                filename="phoenix",
+                local_dir=SPACE_DIR,
+                local_dir_use_symlinks=False,
+            )
+            os.chmod(PHOENIX_BIN, 0o755)
+        except Exception as e:
+            # Fallback: compile from source
+            _update_boot("build", f"Binary download failed, compiling... ({e})")
+            src_path = os.path.join(SPACE_DIR, "phoenix_brain.c")
+            if os.path.exists(src_path):
+                cc = os.environ.get("CC", "cc")
+                cmd = [cc, "-O3", "-std=c11", "-march=native", "-fopenmp",
+                       src_path, "-o", PHOENIX_BIN, "-lm"]
+                result = subprocess.run(cmd, capture_output=True, text=True, timeout=120)
+                if result.returncode != 0:
+                    _update_boot("build", f"Build FAILED: {result.stderr[:500]}")
+                    return
+            else:
+                _update_boot("build", "No binary or source found!")
                 return
-        else:
-            _update_boot("build", "No binary or source found!")
-            return
     _update_boot("build", "Binary ready")
 
     # Phase 3: Start phoenix