diff --git a/capability.go b/capability.go
deleted file mode 100644
index 7b291f38..00000000
--- a/capability.go
+++ /dev/null
@@ -1,36 +0,0 @@
-package core
-
-type Capability byte
-
-const (
-	TCPConnection = Capability(0x01)
-	UDPConnection = Capability(0x02)
-)
-
-type Capabilities interface {
-	HasCapability(cap Capability) bool
-	AddCapability(cap Capability)
-}
-
-type listCapabilities struct {
-	data []Capability
-}
-
-func NewCapabilities() Capabilities {
-	return &listCapabilities{
-		data: make([]Capability, 0, 16),
-	}
-}
-
-func (c *listCapabilities) HasCapability(cap Capability) bool {
-	for _, v := range c.data {
-		if v == cap {
-			return true
-		}
-	}
-	return false
-}
-
-func (c *listCapabilities) AddCapability(cap Capability) {
-	c.data = append(c.data, cap)
-}
diff --git a/capability_test.go b/capability_test.go
deleted file mode 100644
index 100daeb7..00000000
--- a/capability_test.go
+++ /dev/null
@@ -1,21 +0,0 @@
-package core
-
-import (
-	"testing"
-
-	"github.com/v2ray/v2ray-core/testing/unit"
-)
-
-func TestCapabilities(t *testing.T) {
-	assert := unit.Assert(t)
-
-	caps := NewCapabilities()
-	assert.Bool(caps.HasCapability(TCPConnection)).IsFalse()
-
-	caps.AddCapability(TCPConnection)
-	assert.Bool(caps.HasCapability(TCPConnection)).IsTrue()
-
-	caps.AddCapability(UDPConnection)
-	assert.Bool(caps.HasCapability(TCPConnection)).IsTrue()
-	assert.Bool(caps.HasCapability(UDPConnection)).IsTrue()
-}