diff --git a/plan/command/sync_test.go b/plan/command/sync_test.go
new file mode 100644
index 0000000..60d0617
--- /dev/null
+++ b/plan/command/sync_test.go
@@ -0,0 +1,41 @@
+package command_test
+
+import (
+	"testing"
+	"time"
+
+	"github.com/google/go-cmp/cmp"
+	"go-mod.ewintr.nl/planner/item"
+	"go-mod.ewintr.nl/planner/plan/command"
+	"go-mod.ewintr.nl/planner/plan/storage/memory"
+	"go-mod.ewintr.nl/planner/sync/client"
+)
+
+func TestSync(t *testing.T) {
+	t.Parallel()
+
+	syncClient := client.NewMemory()
+	syncRepo := memory.NewSync()
+	localIDRepo := memory.NewLocalID()
+	eventRepo := memory.NewEvent()
+
+	//  now := time.Now()
+
+	it := item.Item{
+		ID:   "a",
+		Kind: item.KindEvent,
+		Body: `{}`,
+	}
+	syncClient.Update([]item.Item{it})
+
+	if err := command.Sync(syncClient, syncRepo, localIDRepo, eventRepo, false); err != nil {
+		t.Errorf("exp nil, got %v", err)
+	}
+	actItems, actErr := syncClient.Updated([]item.Kind{item.KindEvent}, time.Time{})
+	if actErr != nil {
+		t.Errorf("exp nil, got %v", actErr)
+	}
+	if diff := cmp.Diff([]item.Item{it}, actItems); diff != "" {
+		t.Errorf("(exp +, got -)\n%s", diff)
+	}
+}
diff --git a/sync/client/http.go b/sync/client/http.go
new file mode 100644
index 0000000..a94aeba
--- /dev/null
+++ b/sync/client/http.go
@@ -0,0 +1,89 @@
+package client
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+	"time"
+
+	"go-mod.ewintr.nl/planner/item"
+)
+
+type HTTP struct {
+	baseURL string
+	apiKey  string
+	c       *http.Client
+}
+
+func New(url, apiKey string) *HTTP {
+	return &HTTP{
+		baseURL: url,
+		apiKey:  apiKey,
+		c: &http.Client{
+			Timeout: 10 * time.Second,
+		},
+	}
+}
+
+func (c *HTTP) Update(items []item.Item) error {
+	body, err := json.Marshal(items)
+	if err != nil {
+		return fmt.Errorf("could not marhal body: %v", err)
+	}
+	req, err := http.NewRequest(http.MethodPost, fmt.Sprintf("%s/sync", c.baseURL), bytes.NewReader(body))
+	if err != nil {
+		return fmt.Errorf("could not create request: %v", err)
+	}
+	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", c.apiKey))
+
+	res, err := c.c.Do(req)
+	if err != nil {
+		return fmt.Errorf("could not make request: %v", err)
+	}
+	if res.StatusCode != http.StatusNoContent {
+		return fmt.Errorf("server returned status %d", res.StatusCode)
+	}
+
+	return nil
+}
+
+func (c *HTTP) Updated(ks []item.Kind, ts time.Time) ([]item.Item, error) {
+	ksStr := make([]string, 0, len(ks))
+	for _, k := range ks {
+		ksStr = append(ksStr, string(k))
+	}
+	u := fmt.Sprintf("%s/sync?ks=%s", c.baseURL, strings.Join(ksStr, ","))
+	if !ts.IsZero() {
+		u = fmt.Sprintf("%s&ts=", url.QueryEscape(ts.Format(time.RFC3339)))
+	}
+	req, err := http.NewRequest(http.MethodGet, u, nil)
+	if err != nil {
+		return nil, fmt.Errorf("could not create request: %v", err)
+	}
+	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", c.apiKey))
+
+	res, err := c.c.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("could not get response: %v", err)
+	}
+	if res.StatusCode != http.StatusOK {
+		return nil, fmt.Errorf("server returned status %d", res.StatusCode)
+	}
+
+	defer res.Body.Close()
+	body, err := io.ReadAll(res.Body)
+	if err != nil {
+		return nil, fmt.Errorf("could not read response body: %v", err)
+	}
+
+	var items []item.Item
+	if err := json.Unmarshal(body, &items); err != nil {
+		return nil, fmt.Errorf("could not unmarshal response body: %v", err)
+	}
+
+	return items, nil
+}