diff --git a/src/.vscode/settings.json b/src/.vscode/settings.json
new file mode 100644
index 00000000..cc968209
--- /dev/null
+++ b/src/.vscode/settings.json
@@ -0,0 +1,9 @@
+// Place your settings in this file to overwrite default and user settings.
+{
+  "cquery.blacklist": [
+    // ".*libclangmm/.*"
+  ],
+  "cquery.whitelist": [
+    // ".*platform.*.cc"
+  ]
+}
\ No newline at end of file
diff --git a/src/command_line.cc b/src/command_line.cc
index 02ef1ab6..6488e655 100644
--- a/src/command_line.cc
+++ b/src/command_line.cc
@@ -34,7 +34,7 @@ namespace {
 
 const int kNumIndexers = 8 - 1;
 const int kMaxWorkspaceSearchResults = 1000;
-const bool kUseMultipleProcesses = false;
+const bool kUseMultipleProcesses = false; // TODO: initialization options not passed properly when set to true.
 
 
 
@@ -1046,6 +1046,21 @@ void QueryDbMainLoop(
       Ipc_OpenProject* msg = static_cast<Ipc_OpenProject*>(message.get());
       std::string path = msg->project_path;
 
+      std::vector<Matcher> whitelist;
+      std::cerr << "Using whitelist" << std::endl;
+      for (const std::string& entry : msg->whitelist) {
+        std::cerr << " - " << entry << std::endl;
+        whitelist.push_back(Matcher(entry));
+      }
+
+      std::vector<Matcher> blacklist;
+      std::cerr << "Using blacklist" << std::endl;
+      for (const std::string& entry : msg->blacklist) {
+        std::cerr << " - " << entry << std::endl;
+        blacklist.push_back(Matcher(entry));
+      }
+
+
       project->Load(path);
       std::cerr << "Loaded compilation entries (" << project->entries.size() << " files)" << std::endl;
       //for (int i = 0; i < 10; ++i)
@@ -1054,6 +1069,31 @@ void QueryDbMainLoop(
         const CompilationEntry& entry = project->entries[i];
         std::string filepath = entry.filename;
 
+
+        const Matcher* is_bad = nullptr;
+        for (const Matcher& m : whitelist) {
+          if (!m.IsMatch(filepath)) {
+            is_bad = &m;
+            break;
+          }
+        }
+        if (is_bad) {
+          std::cerr << "[" << i << "/" << (project->entries.size() - 1) << "] Failed whitelist check \"" << is_bad->regex_string << "\"; skipping " << filepath << std::endl;
+          continue;
+        }
+
+        for (const Matcher& m : blacklist) {
+          if (m.IsMatch(filepath)) {
+            is_bad = &m;
+            break;
+          }
+        }
+        if (is_bad) {
+          std::cerr << "[" << i << "/" << (project->entries.size() - 1) << "] Failed blacklist check \"" << is_bad->regex_string << "\"; skipping " << filepath << std::endl;
+          continue;
+        }
+
+
         std::cerr << "[" << i << "/" << (project->entries.size() - 1)
           << "] Dispatching index request for file " << filepath
           << std::endl;
@@ -1619,7 +1659,7 @@ void LanguageServerStdinLoop() {
     if (!message)
       continue;
 
-    std::cerr << "[stdin]: Got message \"" << IpcIdToString(message->method_id) << '"' << std::endl;
+    std::cerr << "[stdin] Got message \"" << IpcIdToString(message->method_id) << '"' << std::endl;
     switch (message->method_id) {
       // TODO: For simplicitly lets just proxy the initialize request like
       // all other requests so that stdin loop thread becomes super simple.
@@ -1627,11 +1667,15 @@ void LanguageServerStdinLoop() {
       auto request = static_cast<Ipc_InitializeRequest*>(message.get());
       if (request->params.rootUri) {
         std::string project_path = request->params.rootUri->GetPath();
-        std::cerr << "Initialize in directory " << project_path
+        std::cerr << "[stdin] Initialize in directory " << project_path
           << " with uri " << request->params.rootUri->raw_uri
           << std::endl;
         auto open_project = MakeUnique<Ipc_OpenProject>();
         open_project->project_path = project_path;
+        if (request->params.initializationOptions) {
+          open_project->whitelist = request->params.initializationOptions->whitelist;
+          open_project->blacklist = request->params.initializationOptions->blacklist;
+        }
         ipc->SendMessage(IpcManager::Destination::Server, std::move(open_project));
       }
 
diff --git a/src/fuzzy.cc b/src/fuzzy.cc
index 9cd0ed1d..1592457e 100644
--- a/src/fuzzy.cc
+++ b/src/fuzzy.cc
@@ -3,6 +3,7 @@
 #include <doctest/doctest.h>
 
 Matcher::Matcher(const std::string& search) {
+  /*
   std::string real_search;
   real_search.reserve(search.size() * 3 + 2);
   for (auto c : search) {
@@ -10,8 +11,10 @@ Matcher::Matcher(const std::string& search) {
     real_search += c;
   }
   real_search += ".*";
+  */
 
-  regex = std::regex(real_search,
+  regex_string = search;
+  regex = std::regex(regex_string,
       std::regex_constants::ECMAScript |
       std::regex_constants::icase |
       std::regex_constants::optimize
@@ -19,7 +22,7 @@ Matcher::Matcher(const std::string& search) {
   );
 }
 
-bool Matcher::IsMatch(const std::string& value) {
+bool Matcher::IsMatch(const std::string& value) const {
   //std::smatch match;
   //return std::regex_match(value, match, regex);
   return std::regex_match(value, regex, std::regex_constants::match_any);
diff --git a/src/fuzzy.h b/src/fuzzy.h
index dae20e5f..8d1d1870 100644
--- a/src/fuzzy.h
+++ b/src/fuzzy.h
@@ -5,6 +5,8 @@
 struct Matcher {
   Matcher(const std::string& search);
 
-  bool IsMatch(const std::string& value);
+  bool IsMatch(const std::string& value) const;
+
+  std::string regex_string;
   std::regex regex;
 };
diff --git a/src/ipc.h b/src/ipc.h
index be38e647..dffbb84e 100644
--- a/src/ipc.h
+++ b/src/ipc.h
@@ -58,6 +58,8 @@ MAKE_REFLECT_EMPTY_STRUCT(Ipc_IsAlive);
 struct Ipc_OpenProject : public IpcMessage<Ipc_OpenProject> {
   static constexpr IpcId kIpcId = IpcId::OpenProject;
   std::string project_path;
+  std::vector<std::string> whitelist;
+  std::vector<std::string> blacklist;
 };
 MAKE_REFLECT_STRUCT(Ipc_OpenProject, project_path);
 
diff --git a/src/language_server_api.cc b/src/language_server_api.cc
index 804e117b..70497a86 100644
--- a/src/language_server_api.cc
+++ b/src/language_server_api.cc
@@ -60,6 +60,8 @@ std::unique_ptr<BaseIpcMessage> MessageRegistry::ReadMessageFromStdin() {
     content += c;
   }
 
+  //std::cerr << content.c_str() << std::endl;
+
   rapidjson::Document document;
   document.Parse(content.c_str(), content_length);
   assert(!document.HasParseError());
diff --git a/src/language_server_api.h b/src/language_server_api.h
index 1b89f8a8..3cad0b0e 100644
--- a/src/language_server_api.h
+++ b/src/language_server_api.h
@@ -800,6 +800,11 @@ struct lsClientCapabilities {
 MAKE_REFLECT_STRUCT(lsClientCapabilities, workspace, textDocument);
 
 struct lsInitializeParams {
+  struct lsCustomInitializationOptions {
+    NonElidedVector<std::string> whitelist;
+    NonElidedVector<std::string> blacklist;
+  };
+
   // The process Id of the parent process that started
   // the server. Is null if the process has not been started by another process.
   // If the parent process is not alive then the server should exit (see exit notification) its process.
@@ -817,7 +822,7 @@ struct lsInitializeParams {
   optional<lsDocumentUri> rootUri;
 
   // User provided initialization options.
-  // initializationOptions?: any; // TODO
+  optional<lsCustomInitializationOptions> initializationOptions;
 
   // The capabilities provided by the client (editor or tool)
   lsClientCapabilities capabilities;
@@ -834,7 +839,8 @@ struct lsInitializeParams {
 };
 void Reflect(Reader& reader, lsInitializeParams::lsTrace& value);
 void Reflect(Writer& writer, lsInitializeParams::lsTrace& value);
-MAKE_REFLECT_STRUCT(lsInitializeParams, processId, rootPath, rootUri, capabilities, trace);
+MAKE_REFLECT_STRUCT(lsInitializeParams::lsCustomInitializationOptions, whitelist, blacklist);
+MAKE_REFLECT_STRUCT(lsInitializeParams, processId, rootPath, rootUri, initializationOptions, capabilities, trace);
 
 
 struct lsInitializeError {