diff --git a/bincio/serve/cli.py b/bincio/serve/cli.py
index ae07a44..9825cc0 100644
--- a/bincio/serve/cli.py
+++ b/bincio/serve/cli.py
@@ -20,9 +20,11 @@ console = Console()
 @click.option("--strava-client-secret", default=None, envvar="STRAVA_CLIENT_SECRET", help="Strava OAuth client secret")
 @click.option("--max-users", default=None, type=int, help="Override max users for this instance (0 = unlimited; updates the DB setting)")
 @click.option("--public-url", default=None, envvar="PUBLIC_URL", help="Public base URL (e.g. https://yourdomain.com). Required for Strava OAuth to work behind a reverse proxy.")
+@click.option("--webroot", default=None, type=click.Path(), help="Nginx webroot (e.g. /var/www/bincio). When set, uploads trigger a full Astro build + rsync so new activity pages are immediately accessible without a git push.")
 def serve(data_dir: str, site_dir: Optional[str], host: str, port: int,
           strava_client_id: Optional[str], strava_client_secret: Optional[str],
-          max_users: Optional[int], public_url: Optional[str]) -> None:
+          max_users: Optional[int], public_url: Optional[str],
+          webroot: Optional[str]) -> None:
     """Start the bincio multi-user application server.
 
     Handles auth, user management, and write operations.
@@ -54,6 +56,8 @@ def serve(data_dir: str, site_dir: Optional[str], host: str, port: int,
         srv.strava_client_secret = strava_client_secret
     if public_url:
         srv.public_url = public_url
+    if webroot and site_dir:
+        srv.webroot = Path(webroot).expanduser().resolve()
 
     db = open_db(dd)
     current_limit = get_setting(db, "max_users")
@@ -63,6 +67,8 @@ def serve(data_dir: str, site_dir: Optional[str], host: str, port: int,
     console.print(f"  Data:  [cyan]{dd}[/cyan]")
     if srv.site_dir:
         console.print(f"  Site:  [cyan]{srv.site_dir}[/cyan]")
+    if srv.webroot:
+        console.print(f"  Web:   [cyan]{srv.webroot}[/cyan] (auto-rebuild on upload)")
     console.print(f"  URL:   [cyan]http://{host}:{port}[/cyan]")
     if current_limit and int(current_limit) > 0:
         console.print(f"  Users: [yellow]max {current_limit}[/yellow]")
diff --git a/bincio/serve/server.py b/bincio/serve/server.py
index 52057cf..7126b9c 100644
--- a/bincio/serve/server.py
+++ b/bincio/serve/server.py
@@ -82,6 +82,7 @@ def _job_finish(job_id: str) -> None:
 
 data_dir: Path | None = None
 site_dir: Path | None = None   # for post-write rebuild trigger
+webroot: Path | None = None    # nginx webroot — when set, trigger full rebuild + rsync
 strava_client_id: str = ""
 strava_client_secret: str = ""
 public_url: str = ""   # e.g. "https://yourdomain.com" — used for OAuth redirect URIs
@@ -201,25 +202,67 @@ def _unique_image_name(directory: Path, filename: str) -> str:
 
 # ── Post-write rebuild ────────────────────────────────────────────────────────
 
+# Serialises concurrent rebuilds — only one full build runs at a time.
+# A second upload that arrives while a build is in progress will queue and
+# run after the first finishes, picking up all data written in between.
+_rebuild_lock = threading.Lock()
+
+
 def _trigger_rebuild(handle: str) -> None:
-    """Asynchronously re-merge one user's shard and rewrite the root manifest."""
+    """Asynchronously re-merge and optionally rebuild + rsync the site.
+
+    - Without --webroot: fast path — merges sidecars + rewrites root manifest
+      (~1 s).  New activity pages require the nginx try_files fallback to work.
+    - With --webroot: full Astro build + rsync to the nginx webroot (~30–60 s,
+      serialised).  New activity pages are immediately accessible.
+    """
     if site_dir is None:
         return
     if not _VALID_HANDLE.match(handle):
         return  # safety: never pass untrusted strings to subprocess
+
     uv = shutil.which("uv") or str(Path.home() / ".local" / "bin" / "uv")
-    try:
-        subprocess.Popen(
-            [uv, "run", "bincio", "render",
-             "--data-dir", str(data_dir),
-             "--site-dir", str(site_dir),
-             "--handle", handle,
-             "--no-build"],
-            stdout=subprocess.DEVNULL,
-            stderr=subprocess.DEVNULL,
-        )
-    except Exception:
-        pass  # rebuild failure must never 500 the calling endpoint
+    _data_dir = str(data_dir)
+    _site_dir = str(site_dir)
+    _webroot  = str(webroot) if webroot else None
+    _handle   = handle
+
+    def _run() -> None:
+        try:
+            if _webroot is None:
+                # Fast: only update data, skip Astro build
+                subprocess.run(
+                    [uv, "run", "bincio", "render",
+                     "--data-dir", _data_dir,
+                     "--site-dir", _site_dir,
+                     "--handle", _handle,
+                     "--no-build"],
+                    stdout=subprocess.DEVNULL,
+                    stderr=subprocess.DEVNULL,
+                )
+            else:
+                # Full build + rsync — serialised so concurrent uploads don't race
+                with _rebuild_lock:
+                    result = subprocess.run(
+                        [uv, "run", "bincio", "render",
+                         "--data-dir", _data_dir,
+                         "--site-dir", _site_dir,
+                         "--handle", _handle],
+                        stdout=subprocess.DEVNULL,
+                        stderr=subprocess.DEVNULL,
+                    )
+                    if result.returncode == 0:
+                        # Rsync built site to nginx webroot
+                        subprocess.run(
+                            ["rsync", "-a", "--delete",
+                             f"{_site_dir}/dist/", _webroot + "/"],
+                            stdout=subprocess.DEVNULL,
+                            stderr=subprocess.DEVNULL,
+                        )
+        except Exception:
+            pass  # rebuild failure must never affect the calling request
+
+    threading.Thread(target=_run, daemon=True).start()
 
 
 # ── Auth endpoints ────────────────────────────────────────────────────────────
diff --git a/docs/deployment/vps.md b/docs/deployment/vps.md
index 8842d08..21a9538 100644
--- a/docs/deployment/vps.md
+++ b/docs/deployment/vps.md
@@ -113,6 +113,7 @@ WorkingDirectory=/opt/bincio
 ExecStart=/root/.local/bin/uv run bincio serve \
     --data-dir /var/bincio/data \
     --site-dir /opt/bincio/site \
+    --webroot /var/www/bincio \
     --host 127.0.0.1 \
     --port 4041 \
     --public-url https://yourdomain.com