diff --git a/api_test.go b/api_test.go
index f25b8ac..4b98358 100644
--- a/api_test.go
+++ b/api_test.go
@@ -5,6 +5,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"io"
+	"io/ioutil"
 	"net/http"
 	"net/http/httptest"
 	"net/url"
@@ -508,3 +509,92 @@ func TestDelete(t *testing.T) {
 		}
 	}
 }
+
+func TestRegister(t *testing.T) {
+	db, done := testDB(t)
+	if db == nil {
+		t.Fatalf("could not create temp db")
+	}
+	defer done()
+
+	sm := http.NewServeMux()
+	mm := &mockMail{}
+	NewServer(sm, db, mm, "", window, false)
+	ts := httptest.NewServer(sm)
+
+	u := fmt.Sprintf("%s%s?email=fake@example.com", ts.URL, prefix["register"])
+	req, err := http.NewRequest("POST", u, nil)
+	_, err = http.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatalf("couldn't POST: %v", err)
+	}
+
+	req, err = http.NewRequest(
+		"GET",
+		strings.Replace(mm.msg, "https", "http", -1), //ugly hack to get around https vs http
+		nil,
+	)
+	_, err = http.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatalf("couldn't POST: %v", err)
+	}
+
+	err = db.hasUser("fake@example.com")
+	if err != nil {
+		t.Fatalf("user was no correctly added to database", err)
+	}
+}
+
+func TestRoundTrip(t *testing.T) {
+	db, done := testDB(t)
+	if db == nil {
+		t.Fatalf("could not create temp db")
+	}
+	defer done()
+
+	sm := http.NewServeMux()
+	mm := &mockMail{}
+	NewServer(sm, db, mm, "", window, false)
+	ts := httptest.NewServer(sm)
+
+	u := fmt.Sprintf("%s%s?email=fake@example.com", ts.URL, prefix["register"])
+	req, err := http.NewRequest("POST", u, nil)
+	_, err = http.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatalf("couldn't POST: %v", err)
+	}
+
+	req, err = http.NewRequest(
+		"GET",
+		strings.Replace(mm.msg, "https", "http", -1), //ugly hack to get around https vs http
+		nil,
+	)
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatalf("couldn't POST: %v", err)
+	}
+
+	err = db.hasUser("fake@example.com")
+	if err != nil {
+		t.Fatalf("user was no correctly added to database", err)
+	}
+	bs, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		t.Fatalf("Failed to parse response body", err)
+	}
+	tok := strings.Trim(string(bs), "new token: ")
+
+	u = fmt.Sprintf("%s/foo", ts.URL)
+	body := strings.NewReader(`{"repo": "https://s.mcquay.me/sm/vain"}`)
+	req, err = http.NewRequest("POST", u, body)
+	req.Header.Add("Content-Type", "application/json")
+	req.Header.Add("Authorization", fmt.Sprintf("Bearer %s", tok))
+	resp, err = http.DefaultClient.Do(req)
+	if err != nil {
+		t.Fatalf("couldn't POST: %v", err)
+	}
+
+	if got, want := len(db.Pkgs()), 1; got != want {
+		t.Fatalf("pkgs should have something in it; got %d, want %d", got, want)
+	}
+}
diff --git a/db.go b/db.go
index 197888b..df72de0 100644
--- a/db.go
+++ b/db.go
@@ -312,3 +312,29 @@ func (db *DB) addUser(email string) (string, error) {
 	)
 	return tok, err
 }
+
+func (db *DB) hasUser(email string) error {
+	result, err := db.conn.Query(
+		"SELECT EXISTS(SELECT 1 FROM users WHERE email = ? LIMIT 1)",
+		email,
+	)
+	if err != nil {
+		return verrors.HTTP{
+			Message: fmt.Sprintf("could not find requested user's email: %q: %v", email, err),
+			Code:    http.StatusInternalServerError,
+		}
+	}
+	var exists string
+	for result.Next() {
+		if err := result.Scan(&exists); err != nil {
+			log.Fatal(err)
+		}
+	}
+	if exists == "0" {
+		return verrors.HTTP{
+			Message: fmt.Sprintf("could not find requested user's email: %q: %v", email, err),
+			Code:    http.StatusInternalServerError,
+		}
+	}
+	return nil
+}
diff --git a/mail.go b/mail.go
index b410d6d..e872374 100644
--- a/mail.go
+++ b/mail.go
@@ -52,3 +52,12 @@ func (e Email) Send(to mail.Address, msg string) error {
 	}
 	return err
 }
+
+type mockMail struct {
+	msg string
+}
+
+func (m *mockMail) Send(to mail.Address, msg string) error {
+	m.msg = msg
+	return nil
+}