diff --git a/src/cli/lock/key_test.go b/src/cli/lock/key_test.go
new file mode 100644
index 0000000..0b7184e
--- /dev/null
+++ b/src/cli/lock/key_test.go
@@ -0,0 +1,22 @@
+package lock
+
+import (
+	"encoding/base64"
+	"testing"
+)
+
+func TestGenerateLicenseKey(t *testing.T) {
+	key, err := GenerateLicenseKey()
+	if err != nil {
+		t.Fatalf("GenerateLicenseKey() error = %v", err)
+	}
+	if key == "" {
+		t.Error("GenerateLicenseKey() returned empty string")
+	}
+
+	// Verify it is valid base64
+	_, err = base64.StdEncoding.DecodeString(key)
+	if err != nil {
+		t.Errorf("GenerateLicenseKey() returned invalid base64: %v", err)
+	}
+}
diff --git a/src/cli/tweet/future_test.go b/src/cli/tweet/future_test.go
new file mode 100644
index 0000000..a323343
--- /dev/null
+++ b/src/cli/tweet/future_test.go
@@ -0,0 +1,122 @@
+package tweet
+
+import (
+	"testing"
+)
+
+func TestHandleTweetTime(t *testing.T) {
+	tests := []struct {
+		name        string
+		input       string
+		wantHours   int
+		wantMinutes int
+		wantErr     bool
+	}{
+		{
+			name:        "hours and minutes",
+			input:       "2h3m",
+			wantHours:   2,
+			wantMinutes: 3,
+			wantErr:     false,
+		},
+		{
+			name:        "only hours",
+			input:       "5h",
+			wantHours:   5,
+			wantMinutes: 0,
+			wantErr:     false,
+		},
+		{
+			name:        "only minutes",
+			input:       "30m",
+			wantHours:   0,
+			wantMinutes: 30,
+			wantErr:     false,
+		},
+		{
+			name:        "empty string",
+			input:       "",
+			wantHours:   0,
+			wantMinutes: 0,
+			wantErr:     true,
+		},
+		{
+			name:        "invalid format garbage",
+			input:       "abc",
+			wantHours:   0,
+			wantMinutes: 0,
+			wantErr:     true,
+		},
+		{
+			name:        "missing suffix",
+			input:       "2h3",
+			wantHours:   0,
+			wantMinutes: 0,
+			wantErr:     true,
+		},
+		{
+			name:        "invalid number",
+			input:       "xh",
+			wantHours:   0,
+			wantMinutes: 0,
+			wantErr:     true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gotHours, gotMinutes, err := handleTweetTime(tt.input)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("handleTweetTime() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if gotHours != tt.wantHours {
+				t.Errorf("handleTweetTime() gotHours = %v, want %v", gotHours, tt.wantHours)
+			}
+			if gotMinutes != tt.wantMinutes {
+				t.Errorf("handleTweetTime() gotMinutes = %v, want %v", gotMinutes, tt.wantMinutes)
+			}
+		})
+	}
+}
+
+func TestHandleFutureTweetArgs(t *testing.T) {
+	tests := []struct {
+		name      string
+		args      []string
+		wantTweet string
+		wantTime  string
+		wantErr   bool
+	}{
+		{
+			name:      "valid args",
+			args:      []string{"x", "f", "hello world", "2h"},
+			wantTweet: "hello world",
+			wantTime:  "2h",
+			wantErr:   false,
+		},
+		{
+			name:      "not enough args",
+			args:      []string{"x", "f"},
+			wantTweet: "",
+			wantTime:  "",
+			wantErr:   true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			gotTweet, gotTime, err := handleFutureTweetArgs(tt.args)
+			if (err != nil) != tt.wantErr {
+				t.Errorf("handleFutureTweetArgs() error = %v, wantErr %v", err, tt.wantErr)
+				return
+			}
+			if gotTweet != tt.wantTweet {
+				t.Errorf("handleFutureTweetArgs() gotTweet = %v, want %v", gotTweet, tt.wantTweet)
+			}
+			if gotTime != tt.wantTime {
+				t.Errorf("handleFutureTweetArgs() gotTime = %v, want %v", gotTime, tt.wantTime)
+			}
+		})
+	}
+}