diff --git a/Package.resolved b/Package.resolved
index f125137..2215a3a 100644
--- a/Package.resolved
+++ b/Package.resolved
@@ -9,6 +9,15 @@
         "version" : "1.20.1"
       }
     },
+    {
+      "identity" : "feedkit",
+      "kind" : "remoteSourceControl",
+      "location" : "https://github.com/nmdias/FeedKit",
+      "state" : {
+        "revision" : "68493a33d862c33c9a9f67ec729b3b7df1b20ade",
+        "version" : "9.1.2"
+      }
+    },
     {
       "identity" : "functions-swift",
       "kind" : "remoteSourceControl",
@@ -77,8 +86,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/buhe/openai-kit",
       "state" : {
-        "revision" : "ead156fa2e25e4e469cd837fda08836fb880a834",
-        "version" : "1.8.3"
+        "revision" : "f0c785d22dd14f71a42ad83cedbbddc02591aadb",
+        "version" : "1.8.5"
       }
     },
     {
@@ -102,10 +111,10 @@
     {
       "identity" : "similarity-search-kit",
       "kind" : "remoteSourceControl",
-      "location" : "https://github.com/ZachNagengast/similarity-search-kit.git",
+      "location" : "https://github.com/buhe/similarity-search-kit",
       "state" : {
-        "revision" : "6d78d3051aa35f5701af34f9f49ab793a97c6b76",
-        "version" : "0.0.11"
+        "revision" : "39bbd0b5c2662728792ee9be132212e5fd4a49e2",
+        "version" : "0.0.16"
       }
     },
     {
@@ -149,8 +158,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/apple/swift-collections.git",
       "state" : {
-        "revision" : "d029d9d39c87bed85b1c50adee7c41795261a192",
-        "version" : "1.0.6"
+        "revision" : "94cf62b3ba8d4bed62680a282d4c25f9c63c2efb",
+        "version" : "1.1.0"
       }
     },
     {
@@ -266,8 +275,8 @@
       "kind" : "remoteSourceControl",
       "location" : "https://github.com/buhe/SwiftyNotion",
       "state" : {
-        "revision" : "8ff884579370c0ebbc81ae1d6b8e9b62076d25b7",
-        "version" : "0.1.2"
+        "revision" : "61af40905bfd5eb8cad454e02095dfbdea0498cb",
+        "version" : "0.1.3"
       }
     },
     {
diff --git a/Package.swift b/Package.swift
index f77429d..26fa2e3 100644
--- a/Package.swift
+++ b/Package.swift
@@ -18,16 +18,17 @@ let package = Package(
             targets: ["LangChain"]),
     ],
     dependencies: [
-        .package(url: "https://github.com/buhe/openai-kit", .upToNextMajor(from: "1.8.3")),
+        .package(url: "https://github.com/buhe/openai-kit", .upToNextMajor(from: "1.8.5")),
         .package(url: "https://github.com/supabase-community/supabase-swift", .upToNextMajor(from: "0.2.1")),
         .package(url: "https://github.com/SwiftyJSON/SwiftyJSON", .upToNextMajor(from: "5.0.1")),
         .package(url: "https://github.com/drmohundro/SWXMLHash", .upToNextMajor(from: "7.0.2")),
         .package(url: "https://github.com/scinfu/SwiftSoup", .upToNextMajor(from: "2.6.1")),
         .package(url: "https://github.com/juyan/swift-filestore", .upToNextMajor(from: "0.5.0")),
-        .package(url: "https://github.com/ZachNagengast/similarity-search-kit.git", from: "0.0.11"),
+        .package(url: "https://github.com/buhe/similarity-search-kit", from: "0.0.16"),
         .package(url: "https://github.com/google/generative-ai-swift", .upToNextMajor(from: "0.4.4")),
-        .package(url: "https://github.com/buhe/SwiftyNotion", .upToNextMajor(from: "0.1.2")),
         .package(url: "https://github.com/buhe/llmfarm_core.swift", .branch("langchain")),
+        .package(url: "https://github.com/buhe/SwiftyNotion", .upToNextMajor(from: "0.1.3")),
+        .package(url: "https://github.com/nmdias/FeedKit", .upToNextMajor(from: "9.1.2")),
     ],
     targets: [
         // Targets are the basic building blocks of a package, defining a module or a test suite.
@@ -42,9 +43,11 @@ let package = Package(
                 .product(name: "SwiftSoup", package: "SwiftSoup"),
                 .product(name: "SwiftFileStore", package: "swift-filestore"),
                 .product(name: "SimilaritySearchKit", package: "similarity-search-kit", condition: .when(platforms: [.macOS, .iOS, .visionOS])),
+//                .product(name: "SimilaritySearchKitDistilbert", package: "similarity-search-kit", condition: .when(platforms: [.macOS, .iOS, .visionOS])),
                 .product(name: "GoogleGenerativeAI", package: "generative-ai-swift"),
                 .product(name: "SwiftyNotion", package: "SwiftyNotion"),
                 .product(name: "llmfarm_core", package: "llmfarm_core.swift"),
+                .product(name: "FeedKit", package: "FeedKit"),
             ]
         
         ),
diff --git a/README.md b/README.md
index 35f6a40..bbe3fa1 100644
--- a/README.md
+++ b/README.md
@@ -402,6 +402,7 @@ Task(priority: .background)  {
     - [x] FileStore
 - Embedding
     - [x] OpenAI
+    - [ ] Distilbert
 - Chain
     - [x] Base
     - [x] LLM
@@ -441,6 +442,7 @@ Task(priority: .background)  {
     - [x] ImageOCRLoader
     - [x] AudioLoader
     - [x] NotionLoader
+    - [x] RSSLoader
 - OutputParser
     - [x] MRKLOutputParser
     - [x] ListOutputParser
diff --git a/Sources/LangChain/document_loaders/BaseLoader.swift b/Sources/LangChain/document_loaders/BaseLoader.swift
index d5e0d54..dd1b97b 100644
--- a/Sources/LangChain/document_loaders/BaseLoader.swift
+++ b/Sources/LangChain/document_loaders/BaseLoader.swift
@@ -6,9 +6,16 @@
 //
 
 import Foundation
-public struct Document {
+public struct Document: Equatable {
+    public init(page_content: String, metadata: [String : String]) {
+        self.page_content = page_content
+        self.metadata = metadata
+    }
     public let page_content: String
     public var metadata: [String: String]
+    public static func == (lhs: Document, rhs: Document) -> Bool {
+        return lhs.page_content == rhs.page_content
+    }
 }
 public class BaseLoader {
     
diff --git a/Sources/LangChain/document_loaders/RSSLoader.swift b/Sources/LangChain/document_loaders/RSSLoader.swift
new file mode 100644
index 0000000..619257e
--- /dev/null
+++ b/Sources/LangChain/document_loaders/RSSLoader.swift
@@ -0,0 +1,54 @@
+//
+//  File.swift
+//  
+//
+//  Created by 顾艳华 on 2/10/24.
+//
+
+import Foundation
+import FeedKit
+
+public class RSSLoader: BaseLoader {
+    let url: String
+    
+    public init(url: String, callbacks: [BaseCallbackHandler] = []) {
+        self.url = url
+        super.init(callbacks: callbacks)
+    }
+    public override func _load() async throws  -> [Document] {
+        let feedURL = URL(string: url)!
+        let parser = FeedParser(URL: feedURL)
+        let result = parser.parse()
+        switch result {
+        case .success(let feed):
+            
+            // Grab the parsed feed directly as an optional rss, atom or json feed object
+            switch feed {
+            case let .atom(feed):
+                var content = [Document]()
+                for f in feed.entries ?? [] {
+                    content.append(Document(page_content: f.title ?? "", metadata: [:]))
+                }
+                return content
+            case let .rss(feed):
+                var content = [Document]()
+                for f in feed.items ?? [] {
+                    content.append(Document(page_content: f.title ?? "", metadata: [:]))
+                }
+                return content
+            case let .json(feed):
+                var content = [Document]()
+                for f in feed.items ?? [] {
+                    content.append(Document(page_content: f.title ?? "", metadata: [:]))
+                }
+                return content
+            }
+            
+            
+        case .failure(let error):
+            print(error)
+            return []
+        }
+        
+    }
+}
diff --git a/Sources/LangChain/embeddings/Distilbert.swift b/Sources/LangChain/embeddings/Distilbert.swift
new file mode 100644
index 0000000..0071898
--- /dev/null
+++ b/Sources/LangChain/embeddings/Distilbert.swift
@@ -0,0 +1,22 @@
+////
+////  File.swift
+////  
+////
+////  Created by 顾艳华 on 2/11/24.
+////
+//
+//import Foundation
+//import SimilaritySearchKitDistilbert
+//
+//@available(macOS 13.0, *)
+//public struct Distilbert: Embeddings {
+//    let n = DistilbertEmbeddings()
+//    public init() {
+//        
+//    }
+//    
+//    
+//    public func embedQuery(text: String) async -> [Float] {
+//        await n.encode(sentence: text)!
+//    }
+//}
diff --git a/Sources/LangChain/embeddings/OpenAIEmbeddings.swift b/Sources/LangChain/embeddings/OpenAIEmbeddings.swift
index fc89ba2..ad27c1b 100644
--- a/Sources/LangChain/embeddings/OpenAIEmbeddings.swift
+++ b/Sources/LangChain/embeddings/OpenAIEmbeddings.swift
@@ -11,8 +11,9 @@ import AsyncHTTPClient
 import OpenAIKit
 
 public struct OpenAIEmbeddings: Embeddings {
-    public init() {
-        
+    let session: URLSession
+    public init(session: URLSession = URLSession(configuration: .default)) {
+        self.session = session
     }
     
 //    public func embedDocuments(texts: [String]) -> [[Float]] {
@@ -20,21 +21,16 @@ public struct OpenAIEmbeddings: Embeddings {
 //    }
     
     public func embedQuery(text: String) async -> [Float] {
-        let eventLoopGroup = ThreadManager.thread
        
         let env = Env.loadEnv()
         
         if let apiKey = env["OPENAI_API_KEY"] {
             let baseUrl = env["OPENAI_API_BASE"] ?? "api.openai.com"
             
-            let httpClient = HTTPClient(eventLoopGroupProvider: .shared(eventLoopGroup))
             let configuration = Configuration(apiKey: apiKey, api: API(scheme: .https, host: baseUrl))
 
-            let openAIClient = OpenAIKit.Client(httpClient: httpClient, configuration: configuration)
-            defer {
-                // it's important to shutdown the httpClient after all requests are done, even if one failed. See: https://github.com/swift-server/async-http-client
-                try? httpClient.syncShutdown()
-            }
+            let openAIClient = OpenAIKit.Client(session: session, configuration: configuration)
+
             do {
                 let embedding = try await openAIClient.embeddings.create(input: text)
                 
diff --git a/Sources/LangChain/retriever/MultiVectorRetriever.swift b/Sources/LangChain/retriever/MultiVectorRetriever.swift
index e042bb3..2c2363c 100644
--- a/Sources/LangChain/retriever/MultiVectorRetriever.swift
+++ b/Sources/LangChain/retriever/MultiVectorRetriever.swift
@@ -17,7 +17,7 @@ public class MultiVectorRetriever: BaseRetriever {
     }
     
     public override func _get_relevant_documents(query: String) async throws  -> [Document] {
-        let sub_docs = await self.vectorstore.similaritySearch(query: query, k: 1)
+        let sub_docs = await self.vectorstore.similaritySearch(query: query, k: 2)
         var ids: [String] = []
         for d in sub_docs {
             ids.append(d.metadata[self.id_key]!)
diff --git a/Sources/LangChain/retriever/ParentDocumentRetriever.swift b/Sources/LangChain/retriever/ParentDocumentRetriever.swift
index 8434989..7d5ff8d 100644
--- a/Sources/LangChain/retriever/ParentDocumentRetriever.swift
+++ b/Sources/LangChain/retriever/ParentDocumentRetriever.swift
@@ -4,8 +4,9 @@
 //
 //  Created by 顾艳华 on 2023/11/17.
 //
-
+import CryptoKit
 import Foundation
+
 public class ParentDocumentRetriever: MultiVectorRetriever {
     public init(child_splitter: TextSplitter, parent_splitter: TextSplitter? = nil, vectorstore: VectorStore, docstore: BaseStore) {
         self.child_splitter = child_splitter
@@ -19,7 +20,10 @@ public class ParentDocumentRetriever: MultiVectorRetriever {
     let parent_splitter: TextSplitter?
     //The text splitter to use to create parent documents.
     //If none, then the parent documents will be the raw documents passed in.
-    public func add_documents(documents: [Document]) async {
+    public func add_documents(documents: [Document]) async -> [String] {
+        if documents.isEmpty {
+            return []
+        }
         var parent_documents: [Document]
         if let p = self.parent_splitter {
             parent_documents = p.split_documents(documents: documents)
@@ -42,6 +46,28 @@ public class ParentDocumentRetriever: MultiVectorRetriever {
         await self.vectorstore.add_documents(documents: docs)
         await self.docstore.mset(kvpairs: full_docs)
         print("🚀 End add sub document \(docs.count), main document \(full_docs.count)")
+        return doc_ids
+    }
+    
+    public func remove_documents(documents: [Document]) async {
+        if documents.isEmpty {
+            return
+        }
+        await self.docstore.mdelete(keys: documents.map {$0.metadata["id"]!})
+        var all_sub_docs = [Document]()
+        for main_doc in documents {
+            let sub_docs = self.child_splitter.split_documents(documents: [main_doc])
+            all_sub_docs.append(contentsOf: sub_docs)
+        }
+        print("🚀 Begin remove sub document \(all_sub_docs.count), main document \(documents.count)")
+        await self.vectorstore.remove_documents(sha256s: all_sub_docs.map {sha256(str: $0.page_content)})
+        print("🚀 End remove sub document \(all_sub_docs.count), main document \(documents.count)")
+    }
+    
+    fileprivate func sha256(str: String) -> String {
+        let data = Data(str.utf8)
+        let hash = SHA256.hash(data: data)
+        return hash.compactMap { String(format: "%02x", $0) }.joined()
     }
 //    def add_documents(
 //        self,
diff --git a/Sources/LangChain/schema/LocalFileStore.swift b/Sources/LangChain/schema/LocalFileStore.swift
index bebbe22..e50f6c2 100644
--- a/Sources/LangChain/schema/LocalFileStore.swift
+++ b/Sources/LangChain/schema/LocalFileStore.swift
@@ -102,7 +102,7 @@ public class LocalFileStore: BaseStore {
         var allKeys: [String] = []
         let allSHA = try await objectStore!.readAllKeys(namespace: STORE_NS)
         for sha in allSHA {
-            print("sha: \(sha)")
+//            print("sha: \(sha)")
             if sha == ".DS_Store" {
                 continue
             }
diff --git a/Sources/LangChain/utilities/TextSplitter.swift b/Sources/LangChain/utilities/TextSplitter.swift
index 80be25a..97afa5d 100644
--- a/Sources/LangChain/utilities/TextSplitter.swift
+++ b/Sources/LangChain/utilities/TextSplitter.swift
@@ -92,7 +92,7 @@ public class TextSplitter {
     public func split_text(text: String) -> [String] {
         []
     }
-    func split_documents(documents: [Document]) -> [Document] {
+    public func split_documents(documents: [Document]) -> [Document] {
         var new_documents: [Document] = []
         for doc in documents {
             for chunk in self.split_text(text: doc.page_content){
diff --git a/Sources/LangChain/vectorstores/SimilaritySearchKit.swift b/Sources/LangChain/vectorstores/SimilaritySearchKit.swift
index f48e87b..3495d92 100644
--- a/Sources/LangChain/vectorstores/SimilaritySearchKit.swift
+++ b/Sources/LangChain/vectorstores/SimilaritySearchKit.swift
@@ -9,6 +9,7 @@ import Foundation
 
 #if os(macOS) || os(iOS) || os(visionOS)
 import SimilaritySearchKit
+import CryptoKit
 
 private struct LangChainEmbeddingBridge: EmbeddingsProtocol {
     
@@ -32,7 +33,11 @@ private struct LangChainEmbeddingBridge: EmbeddingsProtocol {
     }
     let embeddings: Embeddings
     func encode(sentence: String) async -> [Float]? {
-        await embeddings.embedQuery(text: sentence)
+        let e = await embeddings.embedQuery(text: sentence)
+        if e.isEmpty {
+            print("⚠️\(sentence.prefix(100))")
+        }
+        return e
     }
     
     
@@ -40,11 +45,22 @@ private struct LangChainEmbeddingBridge: EmbeddingsProtocol {
 public class SimilaritySearchKit: VectorStore {
     let vs: SimilarityIndex
     
-    public init(embeddings: Embeddings) async {
-        self.vs =  await SimilarityIndex(
+    public init(embeddings: Embeddings, autoLoad: Bool = false) {
+        self.vs = SimilarityIndex(
             model: LangChainEmbeddingBridge(embeddings: embeddings),
-            metric: CosineSimilarity()
+            metric: DotProduct()
         )
+        if #available(macOS 13.0, *) {
+            if #available(iOS 16.0, *) {
+                if autoLoad {
+                        let _ = try? vs.loadIndex()
+                    } else {
+                        // Fallback on earlier versions
+                    }
+                }
+        } else {
+            // Fallback on earlier versions
+        }
     }
     
     override func similaritySearch(query: String, k: Int) async -> [MatchedModel] {
@@ -52,7 +68,23 @@ public class SimilaritySearchKit: VectorStore {
     }
     
     override func addText(text: String, metadata: [String: String]) async {
-        await vs.addItem(id: UUID().uuidString, text: text, metadata: metadata)
+        await vs.addItem(id: sha256(str: text), text: text, metadata: metadata)
+    }
+    
+    @available(iOS 16.0, *)
+    @available(macOS 13.0, *)
+    public func writeToFile() {
+        let _ = try? vs.saveIndex()
+    }
+    
+    override func removeText(sha256: String) async {
+        vs.removeItem(id: sha256)
+    }
+    
+    func sha256(str: String) -> String {
+        let data = Data(str.utf8)
+        let hash = SHA256.hash(data: data)
+        return hash.compactMap { String(format: "%02x", $0) }.joined()
     }
 }
 #endif
diff --git a/Sources/LangChain/vectorstores/VectorStore.swift b/Sources/LangChain/vectorstores/VectorStore.swift
index ef10ce3..774bfae 100644
--- a/Sources/LangChain/vectorstores/VectorStore.swift
+++ b/Sources/LangChain/vectorstores/VectorStore.swift
@@ -16,7 +16,9 @@ public class VectorStore {
     func addText(text: String, metadata: [String: String]) async {
         
     }
-    
+    func removeText(sha256: String) async {
+        
+    }
     func similaritySearch(query: String, k: Int) async -> [MatchedModel] {
         []
     }
@@ -29,6 +31,13 @@ public class VectorStore {
         }
     }
     
+    func remove_documents(sha256s: [String]) async {
+        await withTaskGroup(of: Void.self) { [self] group in
+            for sha256 in sha256s {
+                group.addTask { await self.removeText(sha256: sha256)}
+            }
+        }
+    }
 //    def add_documents(self, documents: List[Document], **kwargs: Any) -> List[str]:
 //          """Run more documents through the embeddings and add to the vectorstore.
 //
@@ -43,9 +52,3 @@ public class VectorStore {
 //          metadatas = [doc.metadata for doc in documents]
 //          return self.add_texts(texts, metadatas, **kwargs)
 }
-
-public protocol VectorStoreByUser {
-    func addText(text: String, user_id: String, metadata: [String: String]) async
-    
-    func similaritySearch(query: String, k: Int, user_id: String) async -> [MatchedModel]
-}
diff --git a/Tests/LangChainTests/langchain_swiftTests.swift b/Tests/LangChainTests/langchain_swiftTests.swift
index b2e8aa2..b6044b0 100644
--- a/Tests/LangChainTests/langchain_swiftTests.swift
+++ b/Tests/LangChainTests/langchain_swiftTests.swift
@@ -519,12 +519,15 @@ Action Input: the input to the action
         XCTAssertEqual(keys, ["2"])
     }
     
-    func testNotionLoader() async throws {
-        let l = NotionLoader()
-        let d = await l.load()
-        print("hello")
+    func testSimilaritySearchKitSHA256() throws {
+        let vs = SimilaritySearchKit(embeddings: OpenAIEmbeddings())
+        let originalString = "Hello, World!"
+        let hashedString = vs.sha256(str: originalString)
+        print("🚗\(hashedString)")
+        XCTAssertNotNil(hashedString)
     }
     
+    
 //
 //    func testYoutubeHackClientList() async throws {
 //        let eventLoopGroup = ThreadManager.thread