diff --git a/arduino-ide-extension/src/browser/arduino-frontend-contribution.tsx b/arduino-ide-extension/src/browser/arduino-frontend-contribution.tsx
index 524b15ce..ea346a1d 100644
--- a/arduino-ide-extension/src/browser/arduino-frontend-contribution.tsx
+++ b/arduino-ide-extension/src/browser/arduino-frontend-contribution.tsx
@@ -75,10 +75,11 @@ export class ArduinoFrontendContribution extends DefaultFrontendApplicationContr
         registry.registerCommand(ArduinoCommands.UPLOAD, {
             isVisible: widget => this.isArduinoEditor(widget),
             isEnabled: widget => this.isArduinoEditor(widget),
-            execute: widget => {
+            execute: async widget => {
                 const uri = this.toUri(widget);
                 if (uri) {
-                    this.messageService.info(`Uploading ${uri.toString()}`);
+                    const result = await this.coreService.upload({ uri: uri.toString() });
+                    console.log('upload result', result);
                 }
             }
         });
diff --git a/arduino-ide-extension/src/browser/components/connected-boards.tsx b/arduino-ide-extension/src/browser/components/connected-boards.tsx
index 149701c9..8704862c 100644
--- a/arduino-ide-extension/src/browser/components/connected-boards.tsx
+++ b/arduino-ide-extension/src/browser/components/connected-boards.tsx
@@ -4,40 +4,60 @@ import * as React from 'react';
 import { BoardsService, AttachedBoard } from '../../common/protocol/boards-service';
 
 export class ConnectedBoards extends React.Component<ConnectedBoards.Props, ConnectedBoards.State> {
-
     static TOOLBAR_ID: 'connected-boards-toolbar';
 
+    constructor(props: ConnectedBoards.Props) {
+        super(props);
+        this.state = { boardsLoading: false };
+    }
+
     render(): React.ReactNode {
+        let label = "no board available";
+        if (this.state.boardsLoading) {
+            label = "Loading ...";
+        } else if (!!this.state.current) {
+            label = this.state.current.name;
+        }
+
+        let content = [];
+        if (!!this.state.boards) {
+            content = this.state.boards.map((b, i) => <option value={i} key={i}>{b.name}</option>);
+        } else {
+            content = [ <option key="loading" value="0">{label}</option> ];
+        }
+
         return <div className={ConnectedBoards.Styles.CONNECTED_BOARDS_CLASS}>
-            {this.select(this.state ? this.state.boards : undefined, this.state ? this.state.current : undefined)}
+            <select disabled={!this.state.boards} onChange={this.onBoardSelect.bind(this)}>
+                { content }
+            </select>
         </div>;
     }
 
     componentDidMount(): void {
-        this.props.boardsService.attachedBoards().then(result => {
-            const { boards } = result;
-            this.setState({ boards });
-        });
+        this.reloadBoards();
     }
 
-    private select(boards: AttachedBoard[] | undefined, current: AttachedBoard | undefined): React.ReactNode {
-        // Initial pessimistic.
-        const options = [<option>Loading...</option>];
+    protected async reloadBoards() {
+        this.setState({ boardsLoading: true, boards: undefined, current: undefined });
+        const { boards } = await this.props.boardsService.getAttachedBoards()
+        this.setState({ boards, boardsLoading: false });
+
         if (boards) {
-            options.length = 0;
-            options.push(...boards.map(b => b.name).map(name => <option value={name} key={name}>{name}</option>));
+            this.selectBoard(boards[0]);
         }
-        const onChange = (event: React.ChangeEvent<HTMLSelectElement>) => {
-            const current = (boards || []).find(board => board.name === event.target.value);
-            this.setState({ current });
-        };
-        return <select
-            onChange={onChange}
-            value={current ? current.name : 'Loading...'}
-            name={current ? current.name : 'Loading...'}
-        >
-        {options}
-        </select>
+    }
+
+    protected async onBoardSelect(evt: React.ChangeEvent<HTMLSelectElement>) {
+        const selectedBoard = (this.state.boards || [])[parseInt(evt.target.value, 10)];
+        if (!selectedBoard) {
+            return;
+        }
+        this.selectBoard(selectedBoard);
+    }
+
+    protected async selectBoard(board: AttachedBoard) {
+        await this.props.boardsService.selectBoard(board);
+        this.setState({ current: board });
     }
 
 }
@@ -49,6 +69,7 @@ export namespace ConnectedBoards {
     }
 
     export interface State {
+        boardsLoading: boolean;
         boards?: AttachedBoard[];
         current?: AttachedBoard;
     }
diff --git a/arduino-ide-extension/src/common/protocol/boards-service.ts b/arduino-ide-extension/src/common/protocol/boards-service.ts
index 795d71d0..efd89948 100644
--- a/arduino-ide-extension/src/common/protocol/boards-service.ts
+++ b/arduino-ide-extension/src/common/protocol/boards-service.ts
@@ -3,7 +3,10 @@ import { ArduinoComponent } from "./arduino-component";
 export const BoardsServicePath = '/services/boards-service';
 export const BoardsService = Symbol('BoardsService');
 export interface BoardsService {
-    attachedBoards(): Promise<{ boards: AttachedBoard[] }>;
+    getAttachedBoards(): Promise<{ boards: AttachedBoard[] }>;
+    selectBoard(board: AttachedBoard): Promise<void>;
+    getSelectBoard(): Promise<AttachedBoard | undefined>;
+
     search(options: { query?: string }): Promise<{ items: Board[] }>;
     install(board: Board): Promise<void>;
 }
diff --git a/arduino-ide-extension/src/common/protocol/core-service.ts b/arduino-ide-extension/src/common/protocol/core-service.ts
index 3e443264..8f671a56 100644
--- a/arduino-ide-extension/src/common/protocol/core-service.ts
+++ b/arduino-ide-extension/src/common/protocol/core-service.ts
@@ -2,10 +2,17 @@ export const CoreServicePath = '/services/core-service';
 export const CoreService = Symbol('CoreService');
 export interface CoreService {
     compile(options: CoreService.Compile.Options): Promise<void>;
-    upload(): Promise<void>;
+    upload(options: CoreService.Upload.Options): Promise<void>;
 }
 
 export namespace CoreService {
+
+    export namespace Upload {
+        export interface Options {
+            readonly uri: string;
+        }
+    }
+
     export namespace Compile {
         export interface Options {
             readonly uri: string;
diff --git a/arduino-ide-extension/src/node/arduino-daemon.ts b/arduino-ide-extension/src/node/arduino-daemon.ts
index 87937a09..63a6445e 100644
--- a/arduino-ide-extension/src/node/arduino-daemon.ts
+++ b/arduino-ide-extension/src/node/arduino-daemon.ts
@@ -33,13 +33,13 @@ export class ArduinoDaemon implements BackendApplicationContribution {
             });
             if (daemon.stdout) {
                 daemon.stdout.on('data', data => {
-                    this.toolOutputService.publishNewOutput("daeomn", data.toString());
+                    this.toolOutputService.publishNewOutput("daemon", data.toString());
                     DaemonLog.log(this.logger, data.toString());
                 });
             }
             if (daemon.stderr) {
                 daemon.stderr.on('data', data => {
-                    this.toolOutputService.publishNewOutput("daeomn error", data.toString());
+                    this.toolOutputService.publishNewOutput("daemon error", data.toString());
                     DaemonLog.log(this.logger, data.toString());
                 });
             }
diff --git a/arduino-ide-extension/src/node/boards-service-impl.ts b/arduino-ide-extension/src/node/boards-service-impl.ts
index 16f3f085..882d9e67 100644
--- a/arduino-ide-extension/src/node/boards-service-impl.ts
+++ b/arduino-ide-extension/src/node/boards-service-impl.ts
@@ -10,7 +10,9 @@ export class BoardsServiceImpl implements BoardsService {
     @inject(CoreClientProvider)
     protected readonly coreClientProvider: CoreClientProvider;
 
-    public async attachedBoards(): Promise<{ boards: AttachedBoard[] }> {
+    protected selectedBoard: AttachedBoard | undefined;
+
+    public async getAttachedBoards(): Promise<{ boards: AttachedBoard[] }> {
         const { client, instance } = await this.coreClientProvider.getClient();
 
         const req = new BoardListReq();
@@ -36,6 +38,14 @@ export class BoardsServiceImpl implements BoardsService {
         return { boards: serialBoards.concat(networkBoards) };
     }
 
+    async selectBoard(board: AttachedBoard): Promise<void> {
+        this.selectedBoard = board;
+    }
+
+    async getSelectBoard(): Promise<AttachedBoard | undefined> {
+        return this.selectedBoard;
+    }
+
     async search(options: { query?: string }): Promise<{ items: Board[] }> {
         const { client, instance } = await this.coreClientProvider.getClient();
 
diff --git a/arduino-ide-extension/src/node/core-service-impl.ts b/arduino-ide-extension/src/node/core-service-impl.ts
index 4c56895e..0c8ffa0f 100644
--- a/arduino-ide-extension/src/node/core-service-impl.ts
+++ b/arduino-ide-extension/src/node/core-service-impl.ts
@@ -2,10 +2,11 @@ import { inject, injectable } from 'inversify';
 import { FileSystem } from '@theia/filesystem/lib/common/filesystem';
 import { CoreService } from '../common/protocol/core-service';
 import { CompileReq, CompileResp } from './cli-protocol/compile_pb';
-import { BoardsService } from '../common/protocol/boards-service';
+import { BoardsService, AttachedSerialBoard } from '../common/protocol/boards-service';
 import { CoreClientProvider } from './core-client-provider';
 import * as path from 'path';
 import { ToolOutputServiceServer } from '../common/protocol/tool-output-service';
+import { UploadReq, UploadResp } from './cli-protocol/upload_pb';
 
 @injectable()
 export class CoreServiceImpl implements CoreService {
@@ -32,16 +33,19 @@ export class CoreServiceImpl implements CoreService {
         const sketchpath = path.dirname(sketchFilePath);
 
         const { client, instance } = await this.coreClientProvider.getClient(uri);
-        // const boards = await this.boardsService.connectedBoards();
-        // if (!boards.current) {
-        //     throw new Error(`No selected board. The connected boards were: ${boards.boards}.`);
-        // }
-        // https://github.com/cmaglie/arduino-cli/blob/bd5e78701e7546787649d3cca6b21c5d22d0e438/cli/compile/compile.go#L78-L88
+
+        const currentBoard = await this.boardsService.getSelectBoard();
+        if (!currentBoard) {
+            throw new Error("no board selected");
+        }
+        if (!currentBoard.fqbn) {
+            throw new Error(`selected board (${currentBoard.name}) has no FQBN`);
+        }
 
         const compilerReq = new CompileReq();
         compilerReq.setInstance(instance);
         compilerReq.setSketchpath(sketchpath);
-        compilerReq.setFqbn('arduino:avr:uno'/*boards.current.name*/);
+        compilerReq.setFqbn(currentBoard.fqbn!);
         compilerReq.setPreprocess(false);
         compilerReq.setVerbose(true);
         compilerReq.setQuiet(false);
@@ -57,8 +61,43 @@ export class CoreServiceImpl implements CoreService {
         });
     }
 
-    upload(): Promise<void> {
-        throw new Error("Method not implemented.");
+    async upload(options: CoreService.Upload.Options): Promise<void> {
+        console.log('upload', options);
+        const { uri } = options;
+        const sketchFilePath = await this.fileSystem.getFsPath(options.uri);
+        if (!sketchFilePath) {
+            throw new Error(`Cannot resolve filesystem path for URI: ${uri}.`);
+        }
+        const sketchpath = path.dirname(sketchFilePath);
+
+        const currentBoard = await this.boardsService.getSelectBoard();
+        if (!currentBoard) {
+            throw new Error("no board selected");
+        }
+        if (!currentBoard.fqbn) {
+            throw new Error(`selected board (${currentBoard.name}) has no FQBN`);
+        }
+
+        const { client, instance } = await this.coreClientProvider.getClient(uri);
+
+        const req = new UploadReq();
+        req.setInstance(instance);
+        req.setSketchPath(sketchpath);
+        req.setFqbn(currentBoard.fqbn);
+        if (AttachedSerialBoard.is(currentBoard)) {
+            req.setPort(currentBoard.port);
+        } else {
+            throw new Error("can only upload to serial boards");
+        }
+        const result = client.upload(req);
+        return new Promise<void>((resolve, reject) => {
+            result.on('data', (cr: UploadResp) => {
+                this.toolOutputService.publishNewOutput("upload", new Buffer(cr.getOutStream_asU8()).toString());
+                this.toolOutputService.publishNewOutput("upload error", new Buffer(cr.getErrStream_asU8()).toString());
+            });
+            result.on('error', error => reject(error));
+            result.on('end', () => resolve());
+        });
     }
 
 }