diff --git a/assets/openapi.json b/assets/openapi.json
index 5d46136..6bf6f92 100644
--- a/assets/openapi.json
+++ b/assets/openapi.json
@@ -171,6 +171,301 @@
                     "token_type"
                 ]
             },
+            "StoredEmailResponse": {
+                "type": "object",
+                "properties": {
+                    "Content-Type": {
+                        "type": "string"
+                    },
+                    "From": {
+                        "type": "string"
+                    },
+                    "Message-Id": {
+                        "type": "string"
+                    },
+                    "Mime-Version": {
+                        "type": "string"
+                    },
+                    "Subject": {
+                        "type": "string"
+                    },
+                    "To": {
+                        "type": "string"
+                    },
+                    "sender": {
+                        "type": "string"
+                    },
+                    "recipients": {
+                        "type": "string"
+                    },
+                    "from": {
+                        "type": "string"
+                    },
+                    "subject": {
+                        "type": "string"
+                    },
+                    "body-html": {
+                        "type": "string"
+                    },
+                    "body-plain": {
+                        "type": "string"
+                    },
+                    "attachments": {
+                        "type": "array",
+                        "items": [
+                            {
+                                "type": "object",
+                                "properties": {
+                                    "name": {
+                                        "type": "string"
+                                    },
+                                    "content-type": {
+                                        "type": "string"
+                                    },
+                                    "size": {
+                                        "type": "integer"
+                                    },
+                                    "url": {
+                                        "type": "string"
+                                    }
+                                },
+                                "additionalProperties": false,
+                                "required": [
+                                    "content-type",
+                                    "name",
+                                    "size",
+                                    "url"
+                                ]
+                            }
+                        ],
+                        "minItems": 1,
+                        "maxItems": 1
+                    },
+                    "content-id-map": {
+                        "type": "object",
+                        "properties": {},
+                        "additionalProperties": true
+                    },
+                    "message-headers": {
+                        "type": "array",
+                        "items": {
+                            "type": "array",
+                            "items": [
+                                {
+                                    "type": "string"
+                                },
+                                {
+                                    "type": "string"
+                                }
+                            ],
+                            "minItems": 2,
+                            "maxItems": 2
+                        }
+                    },
+                    "stripped-html": {
+                        "type": "string"
+                    },
+                    "stripped-text": {
+                        "type": "string"
+                    },
+                    "stripped-signature": {
+                        "type": "string"
+                    },
+                    "Content-Transfer-Encoding": {
+                        "type": "string"
+                    },
+                    "X-Mailgun-Tag": {
+                        "type": "string"
+                    },
+                    "X-Mailgun-Template-Name": {
+                        "type": "string"
+                    },
+                    "X-Mailgun-Template-Variables": {
+                        "type": "string"
+                    },
+                    "X-Mailgun-Deliver-By": {
+                        "type": "string"
+                    }
+                },
+                "required": [
+                    "Content-Type",
+                    "From",
+                    "Message-Id",
+                    "Mime-Version",
+                    "Subject",
+                    "To",
+                    "body-html",
+                    "body-plain",
+                    "message-headers",
+                    "recipients",
+                    "sender",
+                    "stripped-html",
+                    "stripped-signature",
+                    "stripped-text"
+                ]
+            },
+            "MessagesQueueStatusAPIResponse": {
+                "type": "object",
+                "properties": {
+                    "regular": {
+                        "type": "object",
+                        "properties": {
+                            "is_disabled": {
+                                "type": "boolean"
+                            },
+                            "disabled": {
+                                "type": "object",
+                                "properties": {
+                                    "until": {
+                                        "type": "string"
+                                    },
+                                    "reason": {
+                                        "type": "string"
+                                    }
+                                },
+                                "additionalProperties": false,
+                                "required": [
+                                    "reason",
+                                    "until"
+                                ]
+                            }
+                        },
+                        "additionalProperties": false,
+                        "required": [
+                            "disabled",
+                            "is_disabled"
+                        ]
+                    },
+                    "scheduled": {
+                        "type": "object",
+                        "properties": {
+                            "is_disabled": {
+                                "type": "boolean"
+                            },
+                            "disabled": {
+                                "type": "object",
+                                "properties": {
+                                    "until": {
+                                        "type": "string"
+                                    },
+                                    "reason": {
+                                        "type": "string"
+                                    }
+                                },
+                                "additionalProperties": false,
+                                "required": [
+                                    "reason",
+                                    "until"
+                                ]
+                            }
+                        },
+                        "additionalProperties": false,
+                        "required": [
+                            "disabled",
+                            "is_disabled"
+                        ]
+                    }
+                },
+                "required": [
+                    "regular",
+                    "scheduled"
+                ]
+            },
+            "SubaccountSendingLimitResponse": {
+                "type": "object",
+                "properties": {
+                    "limit": {
+                        "type": "integer"
+                    },
+                    "current": {
+                        "type": "integer"
+                    },
+                    "period": {
+                        "type": "string"
+                    }
+                },
+                "required": [
+                    "current",
+                    "limit",
+                    "period"
+                ]
+            },
+            "SubaccountSetSendingLimitResponse": {
+                "type": "object",
+                "properties": {
+                    "success": {
+                        "type": "boolean"
+                    }
+                },
+                "required": [
+                    "success"
+                ]
+            },
+            "SubaccountDestroyResponse": {
+                "type": "object",
+                "properties": {
+                    "message": {
+                        "type": "string"
+                    }
+                },
+                "required": [
+                    "message"
+                ]
+            },
+            "ActivateDomainKeyResponse": {
+                "type": "object",
+                "properties": {
+                    "message": {
+                        "type": "string"
+                    },
+                    "authority": {
+                        "type": "string"
+                    },
+                    "selector": {
+                        "type": "string"
+                    },
+                    "active": {
+                        "type": "boolean"
+                    },
+                    "status": {
+                        "type": "integer"
+                    }
+                },
+                "required": [
+                    "active",
+                    "authority",
+                    "message",
+                    "selector",
+                    "status"
+                ]
+            },
+            "DeactivateDomainKeyResponse": {
+                "type": "object",
+                "properties": {
+                    "message": {
+                        "type": "string"
+                    },
+                    "authority": {
+                        "type": "string"
+                    },
+                    "selector": {
+                        "type": "string"
+                    },
+                    "active": {
+                        "type": "boolean"
+                    },
+                    "status": {
+                        "type": "integer"
+                    }
+                },
+                "required": [
+                    "active",
+                    "authority",
+                    "message",
+                    "selector",
+                    "status"
+                ]
+            },
             "FieldErrorResponse": {
                 "type": "object",
                 "properties": {
@@ -1724,6 +2019,12 @@
                     "region": {
                         "type": "string"
                     },
+                    "features": {
+                        "type": "array",
+                        "items": {
+                            "type": "string"
+                        }
+                    },
                     "icon": {
                         "type": "string",
                         "nullable": true
@@ -1751,12 +2052,6 @@
                     "description": {
                         "type": "string"
                     },
-                    "features": {
-                        "type": "array",
-                        "items": {
-                            "type": "string"
-                        }
-                    },
                     "verification_level": {
                         "type": "integer"
                     },
@@ -2115,6 +2410,15 @@
             "InstanceDomainsResponse": {
                 "type": "object",
                 "properties": {
+                    "admin": {
+                        "type": "string"
+                    },
+                    "api": {
+                        "type": "string"
+                    },
+                    "apiEndpoint": {
+                        "type": "string"
+                    },
                     "cdn": {
                         "type": "string"
                     },
@@ -2123,12 +2427,10 @@
                     },
                     "defaultApiVersion": {
                         "type": "string"
-                    },
-                    "apiEndpoint": {
-                        "type": "string"
                     }
                 },
                 "required": [
+                    "api",
                     "apiEndpoint",
                     "cdn",
                     "defaultApiVersion",
@@ -2543,6 +2845,12 @@
                     "id": {
                         "type": "string"
                     },
+                    "features": {
+                        "type": "array",
+                        "items": {
+                            "type": "string"
+                        }
+                    },
                     "icon": {
                         "type": "string"
                     },
@@ -2602,12 +2910,6 @@
                     "description": {
                         "type": "string"
                     },
-                    "features": {
-                        "type": "array",
-                        "items": {
-                            "type": "string"
-                        }
-                    },
                     "verification_level": {
                         "type": "integer"
                     },
@@ -2823,6 +3125,9 @@
                     "flags": {
                         "type": "integer"
                     },
+                    "disabled": {
+                        "type": "boolean"
+                    },
                     "verified": {
                         "type": "boolean"
                     },
@@ -2890,9 +3195,6 @@
                     "premium_usage_flags": {
                         "type": "integer"
                     },
-                    "disabled": {
-                        "type": "boolean"
-                    },
                     "settings": {
                         "$ref": "#/components/schemas/UserSettingsSchema"
                     }
@@ -2950,6 +3252,9 @@
                     "flags": {
                         "type": "integer"
                     },
+                    "disabled": {
+                        "type": "boolean"
+                    },
                     "verified": {
                         "type": "boolean"
                     },
@@ -3017,9 +3322,6 @@
                     "premium_usage_flags": {
                         "type": "integer"
                     },
-                    "disabled": {
-                        "type": "boolean"
-                    },
                     "settings": {
                         "$ref": "#/components/schemas/UserSettingsSchema"
                     }
@@ -3316,6 +3618,12 @@
                     "region": {
                         "type": "string"
                     },
+                    "features": {
+                        "type": "array",
+                        "items": {
+                            "type": "string"
+                        }
+                    },
                     "icon": {
                         "type": "string",
                         "nullable": true
@@ -3343,12 +3651,6 @@
                     "description": {
                         "type": "string"
                     },
-                    "features": {
-                        "type": "array",
-                        "items": {
-                            "type": "string"
-                        }
-                    },
                     "verification_level": {
                         "type": "integer"
                     },
@@ -11842,7 +12144,7 @@
                             "length": {
                                 "type": "integer"
                             },
-                            "__@unscopables@700": {
+                            "__@unscopables@698": {
                                 "type": "object",
                                 "additionalProperties": false,
                                 "patternProperties": {
@@ -11971,17 +12273,17 @@
                                     "remove": {
                                         "type": "boolean"
                                     },
-                                    "__@iterator@698": {
+                                    "__@iterator@696": {
                                         "type": "boolean"
                                     },
-                                    "__@unscopables@700": {
+                                    "__@unscopables@698": {
                                         "type": "boolean"
                                     }
                                 }
                             }
                         },
                         "required": [
-                            "__@unscopables@700",
+                            "__@unscopables@698",
                             "length"
                         ]
                     },
@@ -15347,12 +15649,6 @@
                 },
                 "tags": [
                     "updates"
-                ],
-                "x-badges": [
-                    {
-                        "label": "Spacebar-only",
-                        "color": "red"
-                    }
                 ]
             }
         },
diff --git a/assets/schemas.json b/assets/schemas.json
index e73e88c..4d3646d 100644
--- a/assets/schemas.json
+++ b/assets/schemas.json
@@ -152,6 +152,315 @@
         ],
         "$schema": "http://json-schema.org/draft-07/schema#"
     },
+    "StoredEmailResponse": {
+        "type": "object",
+        "properties": {
+            "Content-Type": {
+                "type": "string"
+            },
+            "From": {
+                "type": "string"
+            },
+            "Message-Id": {
+                "type": "string"
+            },
+            "Mime-Version": {
+                "type": "string"
+            },
+            "Subject": {
+                "type": "string"
+            },
+            "To": {
+                "type": "string"
+            },
+            "sender": {
+                "type": "string"
+            },
+            "recipients": {
+                "type": "string"
+            },
+            "from": {
+                "type": "string"
+            },
+            "subject": {
+                "type": "string"
+            },
+            "body-html": {
+                "type": "string"
+            },
+            "body-plain": {
+                "type": "string"
+            },
+            "attachments": {
+                "type": "array",
+                "items": [
+                    {
+                        "type": "object",
+                        "properties": {
+                            "name": {
+                                "type": "string"
+                            },
+                            "content-type": {
+                                "type": "string"
+                            },
+                            "size": {
+                                "type": "integer"
+                            },
+                            "url": {
+                                "type": "string"
+                            }
+                        },
+                        "additionalProperties": false,
+                        "required": [
+                            "content-type",
+                            "name",
+                            "size",
+                            "url"
+                        ]
+                    }
+                ],
+                "minItems": 1,
+                "maxItems": 1
+            },
+            "content-id-map": {
+                "type": "object",
+                "properties": {},
+                "additionalProperties": true
+            },
+            "message-headers": {
+                "type": "array",
+                "items": {
+                    "type": "array",
+                    "items": [
+                        {
+                            "type": "string"
+                        },
+                        {
+                            "type": "string"
+                        }
+                    ],
+                    "minItems": 2,
+                    "maxItems": 2
+                }
+            },
+            "stripped-html": {
+                "type": "string"
+            },
+            "stripped-text": {
+                "type": "string"
+            },
+            "stripped-signature": {
+                "type": "string"
+            },
+            "Content-Transfer-Encoding": {
+                "type": "string"
+            },
+            "X-Mailgun-Tag": {
+                "type": "string"
+            },
+            "X-Mailgun-Template-Name": {
+                "type": "string"
+            },
+            "X-Mailgun-Template-Variables": {
+                "type": "string"
+            },
+            "X-Mailgun-Deliver-By": {
+                "type": "string"
+            }
+        },
+        "additionalProperties": false,
+        "required": [
+            "Content-Type",
+            "From",
+            "Message-Id",
+            "Mime-Version",
+            "Subject",
+            "To",
+            "body-html",
+            "body-plain",
+            "message-headers",
+            "recipients",
+            "sender",
+            "stripped-html",
+            "stripped-signature",
+            "stripped-text"
+        ],
+        "$schema": "http://json-schema.org/draft-07/schema#"
+    },
+    "MessagesQueueStatusAPIResponse": {
+        "type": "object",
+        "properties": {
+            "regular": {
+                "type": "object",
+                "properties": {
+                    "is_disabled": {
+                        "type": "boolean"
+                    },
+                    "disabled": {
+                        "type": "object",
+                        "properties": {
+                            "until": {
+                                "type": "string"
+                            },
+                            "reason": {
+                                "type": "string"
+                            }
+                        },
+                        "additionalProperties": false,
+                        "required": [
+                            "reason",
+                            "until"
+                        ]
+                    }
+                },
+                "additionalProperties": false,
+                "required": [
+                    "disabled",
+                    "is_disabled"
+                ]
+            },
+            "scheduled": {
+                "type": "object",
+                "properties": {
+                    "is_disabled": {
+                        "type": "boolean"
+                    },
+                    "disabled": {
+                        "type": "object",
+                        "properties": {
+                            "until": {
+                                "type": "string"
+                            },
+                            "reason": {
+                                "type": "string"
+                            }
+                        },
+                        "additionalProperties": false,
+                        "required": [
+                            "reason",
+                            "until"
+                        ]
+                    }
+                },
+                "additionalProperties": false,
+                "required": [
+                    "disabled",
+                    "is_disabled"
+                ]
+            }
+        },
+        "additionalProperties": false,
+        "required": [
+            "regular",
+            "scheduled"
+        ],
+        "$schema": "http://json-schema.org/draft-07/schema#"
+    },
+    "SubaccountSendingLimitResponse": {
+        "type": "object",
+        "properties": {
+            "limit": {
+                "type": "integer"
+            },
+            "current": {
+                "type": "integer"
+            },
+            "period": {
+                "type": "string"
+            }
+        },
+        "additionalProperties": false,
+        "required": [
+            "current",
+            "limit",
+            "period"
+        ],
+        "$schema": "http://json-schema.org/draft-07/schema#"
+    },
+    "SubaccountSetSendingLimitResponse": {
+        "type": "object",
+        "properties": {
+            "success": {
+                "type": "boolean"
+            }
+        },
+        "additionalProperties": false,
+        "required": [
+            "success"
+        ],
+        "$schema": "http://json-schema.org/draft-07/schema#"
+    },
+    "SubaccountDestroyResponse": {
+        "type": "object",
+        "properties": {
+            "message": {
+                "type": "string"
+            }
+        },
+        "additionalProperties": false,
+        "required": [
+            "message"
+        ],
+        "$schema": "http://json-schema.org/draft-07/schema#"
+    },
+    "ActivateDomainKeyResponse": {
+        "type": "object",
+        "properties": {
+            "message": {
+                "type": "string"
+            },
+            "authority": {
+                "type": "string"
+            },
+            "selector": {
+                "type": "string"
+            },
+            "active": {
+                "type": "boolean"
+            },
+            "status": {
+                "type": "integer"
+            }
+        },
+        "additionalProperties": false,
+        "required": [
+            "active",
+            "authority",
+            "message",
+            "selector",
+            "status"
+        ],
+        "$schema": "http://json-schema.org/draft-07/schema#"
+    },
+    "DeactivateDomainKeyResponse": {
+        "type": "object",
+        "properties": {
+            "message": {
+                "type": "string"
+            },
+            "authority": {
+                "type": "string"
+            },
+            "selector": {
+                "type": "string"
+            },
+            "active": {
+                "type": "boolean"
+            },
+            "status": {
+                "type": "integer"
+            }
+        },
+        "additionalProperties": false,
+        "required": [
+            "active",
+            "authority",
+            "message",
+            "selector",
+            "status"
+        ],
+        "$schema": "http://json-schema.org/draft-07/schema#"
+    },
     "FieldErrorResponse": {
         "type": "object",
         "properties": {
@@ -1784,6 +2093,12 @@
             "region": {
                 "type": "string"
             },
+            "features": {
+                "type": "array",
+                "items": {
+                    "type": "string"
+                }
+            },
             "icon": {
                 "type": [
                     "null",
@@ -1817,12 +2132,6 @@
             "description": {
                 "type": "string"
             },
-            "features": {
-                "type": "array",
-                "items": {
-                    "type": "string"
-                }
-            },
             "verification_level": {
                 "type": "integer"
             },
@@ -2205,6 +2514,15 @@
     "InstanceDomainsResponse": {
         "type": "object",
         "properties": {
+            "admin": {
+                "type": "string"
+            },
+            "api": {
+                "type": "string"
+            },
+            "apiEndpoint": {
+                "type": "string"
+            },
             "cdn": {
                 "type": "string"
             },
@@ -2213,13 +2531,11 @@
             },
             "defaultApiVersion": {
                 "type": "string"
-            },
-            "apiEndpoint": {
-                "type": "string"
             }
         },
         "additionalProperties": false,
         "required": [
+            "api",
             "apiEndpoint",
             "cdn",
             "defaultApiVersion",
@@ -2668,6 +2984,12 @@
             "id": {
                 "type": "string"
             },
+            "features": {
+                "type": "array",
+                "items": {
+                    "type": "string"
+                }
+            },
             "icon": {
                 "type": "string"
             },
@@ -2731,12 +3053,6 @@
             "description": {
                 "type": "string"
             },
-            "features": {
-                "type": "array",
-                "items": {
-                    "type": "string"
-                }
-            },
             "verification_level": {
                 "type": "integer"
             },
@@ -2960,6 +3276,9 @@
             "flags": {
                 "type": "integer"
             },
+            "disabled": {
+                "type": "boolean"
+            },
             "verified": {
                 "type": "boolean"
             },
@@ -3027,9 +3346,6 @@
             "premium_usage_flags": {
                 "type": "integer"
             },
-            "disabled": {
-                "type": "boolean"
-            },
             "settings": {
                 "$ref": "#/definitions/UserSettingsSchema"
             }
@@ -3092,6 +3408,9 @@
             "flags": {
                 "type": "integer"
             },
+            "disabled": {
+                "type": "boolean"
+            },
             "verified": {
                 "type": "boolean"
             },
@@ -3159,9 +3478,6 @@
             "premium_usage_flags": {
                 "type": "integer"
             },
-            "disabled": {
-                "type": "boolean"
-            },
             "settings": {
                 "$ref": "#/definitions/UserSettingsSchema"
             }
@@ -3488,6 +3804,12 @@
             "region": {
                 "type": "string"
             },
+            "features": {
+                "type": "array",
+                "items": {
+                    "type": "string"
+                }
+            },
             "icon": {
                 "type": [
                     "null",
@@ -3521,12 +3843,6 @@
             "description": {
                 "type": "string"
             },
-            "features": {
-                "type": "array",
-                "items": {
-                    "type": "string"
-                }
-            },
             "verification_level": {
                 "type": "integer"
             },
@@ -12580,7 +12896,7 @@
                     "length": {
                         "type": "integer"
                     },
-                    "__@unscopables@700": {
+                    "__@unscopables@698": {
                         "type": "object",
                         "additionalProperties": false,
                         "patternProperties": {
@@ -12709,17 +13025,17 @@
                             "remove": {
                                 "type": "boolean"
                             },
-                            "__@iterator@698": {
+                            "__@iterator@696": {
                                 "type": "boolean"
                             },
-                            "__@unscopables@700": {
+                            "__@unscopables@698": {
                                 "type": "boolean"
                             }
                         }
                     }
                 },
                 "required": [
-                    "__@unscopables@700",
+                    "__@unscopables@698",
                     "length"
                 ]
             },
diff --git a/src/util/util/Config.ts b/src/util/util/Config.ts
index 2fd9c0f..a79c908 100644
--- a/src/util/util/Config.ts
+++ b/src/util/util/Config.ts
@@ -54,7 +54,9 @@
 
 		config = OrmUtils.mergeDeep({}, { ...new ConfigValue() }, config);
 
-		return this.set(config);
+		await this.set(config);
+		validateFinalConfig(config);
+		return config;
 	};
 	public static get() {
 		if (!config) {
@@ -169,3 +171,38 @@
 
 	return config;
 };
+
+function validateFinalConfig(config: ConfigValue) {
+	let hasErrors = false;
+	function assertConfig(path: string, condition: (val: any) => boolean, recommendedValue: string) {
+		// _ to separate keys
+		const keys = path.split("_");
+		let obj: any = config;
+
+		for (const key of keys) {
+			if (obj == null || !(key in obj)) {
+				console.warn(`[Config] Missing config value for '${path}'. Recommended value: ${recommendedValue}`);
+				return;
+			}
+			obj = obj[key];
+		}
+
+		if (!condition(obj)) {
+			console.warn(`[Config] Invalid config value for '${path}': ${obj}. Recommended value: ${recommendedValue}`);
+			hasErrors = true;
+		}
+	}
+
+	assertConfig("api_endpointPublic", v => v != null, "A valid public API endpoint URL, ex. \"http://localhost:3001/api/v9\"");
+	assertConfig("cdn_endpointPublic", v => v != null, "A valid public CDN endpoint URL, ex. \"http://localhost:3002/\"");
+	assertConfig("cdn_endpointPrivate", v => v != null, "A valid private CDN endpoint URL, ex. \"http://localhost:3002/\" - must be routable from the API server!");
+	assertConfig("gateway_endpointPublic", v => v != null, "A valid public gateway endpoint URL, ex. \"ws://localhost:3003/\"");
+
+	if (hasErrors) {
+		console.error(
+			"[Config] Your config has invalid values. Fix them first https://docs.spacebar.chat/setup/server/configuration",
+		);
+		console.error("[Config] Hint: if you're just testing with bundle (`npm run start`), you can set all endpoint URLs to [proto]://localhost:3001");
+		process.exit(1);
+	} else console.log("[Config] Configuration validated successfully.");
+}
\ No newline at end of file