diff --git a/app/main.py b/app/main.py
index 1c4cc79..a4f410a 100644
--- a/app/main.py
+++ b/app/main.py
@@ -70,6 +70,19 @@ MEMBERS_GROUP_ID = os.environ.get("MEMBERS_GROUP_ID", "")
 # being deleted) so they lose access but can reclaim their data on reactivation.
 INACTIVE_GROUP_ID = os.environ.get("INACTIVE_GROUP_ID", "")
 
+# Loomio integration (forum.inference.coop). The portal reconciles the Loomio
+# group to the current active-member list via the User API (/api/b2).
+LOOMIO_BASE = os.environ.get("LOOMIO_BASE", "https://forum.inference.coop")
+LOOMIO_API_KEY = os.environ.get("LOOMIO_API_KEY", "")
+LOOMIO_GROUP_ID = os.environ.get("LOOMIO_GROUP_ID", "")
+# Operator accounts that must always remain in the Loomio group (never removed
+# by the remove_absent reconciliation), comma-separated.
+LOOMIO_ALWAYS_KEEP = [
+    e.strip()
+    for e in os.environ.get("LOOMIO_ALWAYS_KEEP", "info@inference.coop,bot@inference.coop").split(",")
+    if e.strip()
+]
+
 # Persistent store (SQLite) for email → LiteLLM key token mapping.
 # Lives in /app/data (Cloudron localstorage addon persists this).
 DB_PATH = os.environ.get("DB_PATH", "/app/data/members.db")
@@ -160,6 +173,62 @@ async def is_active_member(slug: str) -> bool:
     return False
 
 
+async def get_active_member_emails() -> list[str]:
+    """Return the list of active financial contributor emails from Open Collective."""
+    query = (
+        '{ collective(slug: "%s") { members(limit: 100) { nodes { role account { email slug } } } } }'
+        % OC_COLLECTIVE_SLUG
+    )
+    async with httpx.AsyncClient() as client:
+        r = await client.post(OC_GRAPHQL_URL, json={"query": query})
+        if r.status_code != 200:
+            logger.warning("OC member list fetch failed: %s", r.status_code)
+            return []
+        nodes = r.json().get("data", {}).get("collective", {}).get("members", {}).get("nodes", [])
+    emails = []
+    for n in nodes:
+        role = n.get("role", "")
+        acct = n.get("account", {}) or {}
+        email = acct.get("email")
+        if role in ("BACKER", "ADMIN") and email:
+            emails.append(email)
+    return emails
+
+
+async def sync_loomio_memberships() -> None:
+    """Reconcile the Loomio group to the current active-member list.
+
+    Uses POST /api/b2/memberships with remove_absent=1, which adds new members
+    and removes anyone not in the list. Operator accounts (LOOMIO_ALWAYS_KEEP)
+    are always included so they are never removed.
+    """
+    if not LOOMIO_API_KEY or not LOOMIO_GROUP_ID:
+        logger.warning("Loomio not configured; skipping membership sync")
+        return
+
+    emails = await get_active_member_emails()
+    # Always keep operator accounts in the group.
+    for keep in LOOMIO_ALWAYS_KEEP:
+        if keep not in emails:
+            emails.append(keep)
+
+    async with httpx.AsyncClient() as client:
+        r = await client.post(
+            f"{LOOMIO_BASE}/api/b2/memberships",
+            headers={"Authorization": f"Bearer {LOOMIO_API_KEY}"},
+            json={"group_id": int(LOOMIO_GROUP_ID), "emails": emails, "remove_absent": 1},
+        )
+        if r.status_code != 200:
+            logger.warning("Loomio membership sync failed: %s %s", r.status_code, r.text[:200])
+            return
+        result = r.json()
+        logger.info(
+            "Loomio sync: added=%s removed=%s",
+            result.get("added_emails", []),
+            result.get("removed_emails", []),
+        )
+
+
 def store_member(email: str, key_token: str, cloudron_user_id: str, slug: str = "") -> None:
     conn = get_db()
     conn.execute(
@@ -400,6 +469,7 @@ async def opencollective_webhook(request: Request, token: str):
                     await cloudron_set_group(member["cloudron_user_id"], INACTIVE_GROUP_ID)
                 # Mark inactive in our DB (key injector will refuse requests)
                 deactivate_member(member["email"])
+                await sync_loomio_memberships()
                 logger.info("Deactivated member %s (slug=%s)", member["email"], slug)
                 return JSONResponse({"status": "deactivated", "email": member["email"]})
         return JSONResponse({"status": "deactivated", "note": "no matching member"})
@@ -591,6 +661,7 @@ async def oauth_callback(request: Request):
     key_token = await litellm_create_key(email, MEMBER_BUDGET)
     store_member(email, key_token, user_id, slug)
     await cloudron_send_invite(user_id, email)
+    await sync_loomio_memberships()
 
     logger.info("Provisioned member %s (user_id=%s)", email, user_id)