diff --git a/gateway/platforms/dingtalk.py b/gateway/platforms/dingtalk.py
index 579c382c704..06b30db7b04 100644
--- a/gateway/platforms/dingtalk.py
+++ b/gateway/platforms/dingtalk.py
@@ -111,9 +111,33 @@ DINGTALK_TYPE_MAPPING = {
 
 
 def check_dingtalk_requirements() -> bool:
-    """Check if DingTalk dependencies are available and configured."""
+    """Check if DingTalk dependencies are available and configured.
+
+    Lazy-installs dingtalk-stream via ``tools.lazy_deps.ensure("platform.dingtalk")``
+    on first call if not present.
+    """
+    global DINGTALK_STREAM_AVAILABLE, dingtalk_stream, ChatbotMessage, CallbackMessage, AckMessage
+    global HTTPX_AVAILABLE, httpx
     if not DINGTALK_STREAM_AVAILABLE or not HTTPX_AVAILABLE:
-        return False
+        try:
+            from tools.lazy_deps import ensure as _lazy_ensure
+            _lazy_ensure("platform.dingtalk", prompt=False)
+        except Exception:
+            return False
+        try:
+            import dingtalk_stream as _ds
+            from dingtalk_stream import ChatbotMessage as _CM
+            from dingtalk_stream.frames import CallbackMessage as _CBM, AckMessage as _AM
+            import httpx as _httpx
+        except ImportError:
+            return False
+        dingtalk_stream = _ds
+        ChatbotMessage = _CM
+        CallbackMessage = _CBM
+        AckMessage = _AM
+        httpx = _httpx
+        DINGTALK_STREAM_AVAILABLE = True
+        HTTPX_AVAILABLE = True
     if not os.getenv("DINGTALK_CLIENT_ID") or not os.getenv("DINGTALK_CLIENT_SECRET"):
         return False
     return True
diff --git a/gateway/platforms/feishu.py b/gateway/platforms/feishu.py
index ae3f7075104..e7be062e84c 100644
--- a/gateway/platforms/feishu.py
+++ b/gateway/platforms/feishu.py
@@ -1343,8 +1343,25 @@ def _run_official_feishu_ws_client(ws_client: Any, adapter: Any) -> None:
 
 
 def check_feishu_requirements() -> bool:
-    """Check if Feishu/Lark dependencies are available."""
-    return FEISHU_AVAILABLE
+    """Check if Feishu/Lark dependencies are available.
+
+    Lazy-installs lark-oapi via ``tools.lazy_deps.ensure("platform.feishu")``
+    on first call if not present.
+    """
+    global FEISHU_AVAILABLE
+    if FEISHU_AVAILABLE:
+        return True
+    try:
+        from tools.lazy_deps import ensure as _lazy_ensure
+        _lazy_ensure("platform.feishu", prompt=False)
+    except Exception:
+        return False
+    try:
+        import lark_oapi  # noqa: F401
+    except ImportError:
+        return False
+    FEISHU_AVAILABLE = True
+    return True
 
 
 class FeishuAdapter(BasePlatformAdapter):
diff --git a/gateway/platforms/matrix.py b/gateway/platforms/matrix.py
index 0133dc2dac7..12075e67837 100644
--- a/gateway/platforms/matrix.py
+++ b/gateway/platforms/matrix.py
@@ -224,7 +224,11 @@ def _check_e2ee_deps() -> bool:
 
 
 def check_matrix_requirements() -> bool:
-    """Return True if the Matrix adapter can be used."""
+    """Return True if the Matrix adapter can be used.
+
+    Lazy-installs mautrix via ``tools.lazy_deps.ensure("platform.matrix")``
+    on first call if not present.
+    """
     token = os.getenv("MATRIX_ACCESS_TOKEN", "")
     password = os.getenv("MATRIX_PASSWORD", "")
     homeserver = os.getenv("MATRIX_HOMESERVER", "")
@@ -238,10 +242,15 @@ def check_matrix_requirements() -> bool:
     try:
         import mautrix  # noqa: F401
     except ImportError:
-        logger.warning(
-            "Matrix: mautrix not installed. Run: pip install 'mautrix[encryption]'"
-        )
-        return False
+        try:
+            from tools.lazy_deps import ensure as _lazy_ensure
+            _lazy_ensure("platform.matrix", prompt=False)
+            import mautrix  # noqa: F401, F811
+        except Exception:
+            logger.warning(
+                "Matrix: mautrix not installed. Run: pip install 'mautrix[encryption]'"
+            )
+            return False
 
     # If encryption is requested, verify E2EE deps are available at startup
     # rather than silently degrading to plaintext-only at connect time.
diff --git a/gateway/platforms/slack.py b/gateway/platforms/slack.py
index 7fbefd446ca..432b01d80bf 100644
--- a/gateway/platforms/slack.py
+++ b/gateway/platforms/slack.py
@@ -73,8 +73,30 @@ class _ThreadContextCache:
 
 
 def check_slack_requirements() -> bool:
-    """Check if Slack dependencies are available."""
-    return SLACK_AVAILABLE
+    """Check if Slack dependencies are available.
+
+    Lazy-installs slack-bolt/slack-sdk via ``tools.lazy_deps.ensure("platform.slack")``
+    on first call if not present.
+    """
+    global SLACK_AVAILABLE, AsyncApp, AsyncSocketModeHandler, AsyncWebClient
+    if SLACK_AVAILABLE:
+        return True
+    try:
+        from tools.lazy_deps import ensure as _lazy_ensure
+        _lazy_ensure("platform.slack", prompt=False)
+    except Exception:
+        return False
+    try:
+        from slack_bolt.async_app import AsyncApp as _App
+        from slack_bolt.adapter.socket_mode.async_handler import AsyncSocketModeHandler as _Handler
+        from slack_sdk.web.async_client import AsyncWebClient as _Client
+    except ImportError:
+        return False
+    AsyncApp = _App
+    AsyncSocketModeHandler = _Handler
+    AsyncWebClient = _Client
+    SLACK_AVAILABLE = True
+    return True
 
 
 def _extract_text_from_slack_blocks(blocks: list) -> str:
diff --git a/tools/lazy_deps.py b/tools/lazy_deps.py
index d086d117307..6e298c23320 100644
--- a/tools/lazy_deps.py
+++ b/tools/lazy_deps.py
@@ -120,6 +120,7 @@ LAZY_DEPS: dict[str, tuple[str, ...]] = {
     "platform.slack": (
         "slack-bolt==1.27.0",
         "slack-sdk==3.40.1",
+        "aiohttp==3.13.3",
     ),
     "platform.matrix": (
         "mautrix[encryption]==0.21.0",