diff --git a/arduino-ide-extension/package.json b/arduino-ide-extension/package.json
index 35349b3b..56dd4ead 100644
--- a/arduino-ide-extension/package.json
+++ b/arduino-ide-extension/package.json
@@ -9,7 +9,9 @@
     "@theia/filesystem": "next",
     "@theia/languages": "next",
     "@theia/monaco": "next",
-    "@theia/workspace": "next"
+    "@theia/workspace": "next",
+    "@types/p-queue": "^3.2.1",
+    "p-queue": "^5.0.0"
   },
   "scripts": {
     "generate-protoc": "./scripts/generate-protoc.sh",
diff --git a/arduino-ide-extension/src/node/core-client-provider-impl.ts b/arduino-ide-extension/src/node/core-client-provider-impl.ts
index 85da6698..b12d1903 100644
--- a/arduino-ide-extension/src/node/core-client-provider-impl.ts
+++ b/arduino-ide-extension/src/node/core-client-provider-impl.ts
@@ -8,10 +8,13 @@ import URI from '@theia/core/lib/common/uri';
 import { CoreClientProvider, Client } from './core-client-provider';
 import * as fs from 'fs';
 import * as path from 'path';
+import * as PQueue from 'p-queue';
 
 @injectable()
 export class CoreClientProviderImpl implements CoreClientProvider {
 
+    protected readonly clientRequestQueue = new PQueue({ autoStart: true, concurrency: 1 });
+
     @inject(FileSystem)
     protected readonly fileSystem: FileSystem;
 
@@ -21,20 +24,24 @@ export class CoreClientProviderImpl implements CoreClientProvider {
     protected clients = new Map<string, Client>();
 
     async getClient(workspaceRootOrResourceUri?: string): Promise<Client> {
-        const roots = await this.workspaceServiceExt.roots();
-        if (!workspaceRootOrResourceUri) {
-            return this.getOrCreateClient(roots[0]);
-        }
-        const root = roots
-            .sort((left, right) => right.length - left.length) // Longest "paths" first
-            .map(uri => new URI(uri))
-            .find(uri => uri.isEqualOrParent(new URI(workspaceRootOrResourceUri)));
-        if (!root) {
-            console.warn(`Could not retrieve the container workspace root for URI: ${workspaceRootOrResourceUri}.`);
-            console.warn(`Falling back to ${roots[0]}`);
-            return this.getOrCreateClient(roots[0]);
-        }
-        return this.getOrCreateClient(root.toString());
+        return this.clientRequestQueue.add(() => new Promise<Client>(async resolve => {
+            const roots = await this.workspaceServiceExt.roots();
+            if (!workspaceRootOrResourceUri) {
+                resolve(this.getOrCreateClient(roots[0]));
+                return;
+            }
+            const root = roots
+                .sort((left, right) => right.length - left.length) // Longest "paths" first
+                .map(uri => new URI(uri))
+                .find(uri => uri.isEqualOrParent(new URI(workspaceRootOrResourceUri)));
+            if (!root) {
+                console.warn(`Could not retrieve the container workspace root for URI: ${workspaceRootOrResourceUri}.`);
+                console.warn(`Falling back to ${roots[0]}`);
+                resolve(this.getOrCreateClient(roots[0]));
+                return;
+            }
+            resolve(this.getOrCreateClient(root.toString()));
+        }));
     }
 
     protected async getOrCreateClient(rootUri: string): Promise<Client> {
diff --git a/arduino-ide-extension/src/node/library-service-impl.ts b/arduino-ide-extension/src/node/library-service-impl.ts
index 9d435d21..5684651e 100644
--- a/arduino-ide-extension/src/node/library-service-impl.ts
+++ b/arduino-ide-extension/src/node/library-service-impl.ts
@@ -1,10 +1,23 @@
-import { injectable } from 'inversify';
+import { injectable, inject } from 'inversify';
 import { Library, LibraryService } from '../common/protocol/library-service';
+import { CoreClientProvider } from './core-client-provider';
+import { LibrarySearchReq, LibrarySearchResp } from './cli-protocol/lib_pb';
 
 @injectable()
 export class LibraryServiceImpl implements LibraryService {
 
+    @inject(CoreClientProvider)
+    protected readonly coreClientProvider: CoreClientProvider;
+
     async search(options: { query?: string; }): Promise<{ items: Library[] }> {
+        const { client, instance } = await this.coreClientProvider.getClient();
+
+        const req = new LibrarySearchReq();
+        req.setQuery(options.query || '');
+        req.setInstance(instance);
+        const resp = await new Promise<LibrarySearchResp>((resolve, reject) => client.librarySearch(req, (err, resp) => !!err ? reject(err) : resolve(resp)));
+        console.log(resp.getSearchOutputList());
+
         const { query } = options;
         const allItems: Library[] = [
             <Library>{
diff --git a/yarn.lock b/yarn.lock
index d061540e..526985e5 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1285,6 +1285,13 @@
   resolved "https://registry.yarnpkg.com/@types/node/-/node-8.10.46.tgz#12161db48a775e8c69c1cfff2be545610381056f"
   integrity sha512-PfnRbk836fFs9T9QnZh0G1k9oC6YXCqIK3LX6vU/6oiXtEBSFCiJFj6UnLZtqIIHTsgMn8Dojq3yhmpwY7QWcw==
 
+"@types/p-queue@^3.2.1":
+  version "3.2.1"
+  resolved "https://registry.yarnpkg.com/@types/p-queue/-/p-queue-3.2.1.tgz#614957d9ed05cf6e02d08ed8f09041c4d100ef70"
+  integrity sha512-tgAdn5zEs05NuHzOyRM34cMO0rczStphR/kLo/ZJwwwJ5S2+QVxwA6gST3vDHWPB1oDfUuT6wOouhJvJkBCA0w==
+  dependencies:
+    p-queue "*"
+
 "@types/prop-types@*":
   version "15.7.1"
   resolved "https://registry.yarnpkg.com/@types/prop-types/-/prop-types-15.7.1.tgz#f1a11e7babb0c3cad68100be381d1e064c68f1f6"
@@ -4638,6 +4645,11 @@ etag@~1.8.1:
   resolved "https://registry.yarnpkg.com/etag/-/etag-1.8.1.tgz#41ae2eeb65efa62268aebfea83ac7d79299b0887"
   integrity sha1-Qa4u62XvpiJorr/qg6x9eSmbCIc=
 
+eventemitter3@^3.1.0:
+  version "3.1.2"
+  resolved "https://registry.yarnpkg.com/eventemitter3/-/eventemitter3-3.1.2.tgz#2d3d48f9c346698fce83a85d7d664e98535df6e7"
+  integrity sha512-tvtQIeLVHjDkJYnzf2dgVMxfuSGJeM/7UCG17TT4EumTfNtF+0nebF/4zWOIkCreAbtNqhGEboB6BWrwqNaw4Q==
+
 events@^3.0.0:
   version "3.0.0"
   resolved "https://registry.yarnpkg.com/events/-/events-3.0.0.tgz#9a0a0dfaf62893d92b875b8f2698ca4114973e88"
@@ -8184,6 +8196,13 @@ p-pipe@^1.2.0:
   resolved "https://registry.yarnpkg.com/p-pipe/-/p-pipe-1.2.0.tgz#4b1a11399a11520a67790ee5a0c1d5881d6befe9"
   integrity sha1-SxoROZoRUgpneQ7loMHViB1r7+k=
 
+p-queue@*, p-queue@^5.0.0:
+  version "5.0.0"
+  resolved "https://registry.yarnpkg.com/p-queue/-/p-queue-5.0.0.tgz#80f1741d5e78a6fa72fce889406481baa5617a3c"
+  integrity sha512-6QfeouDf236N+MAxHch0CVIy8o/KBnmhttKjxZoOkUlzqU+u9rZgEyXH3OdckhTgawbqf5rpzmyR+07+Lv0+zg==
+  dependencies:
+    eventemitter3 "^3.1.0"
+
 p-reduce@^1.0.0:
   version "1.0.0"
   resolved "https://registry.yarnpkg.com/p-reduce/-/p-reduce-1.0.0.tgz#18c2b0dd936a4690a529f8231f58a0fdb6a47dfa"