diff --git a/ipblocklist/files/mem.go b/ipblocklist/files/mem.go
new file mode 100644
index 0000000..8668612
--- /dev/null
+++ b/ipblocklist/files/mem.go
@@ -0,0 +1,37 @@
+package files
+
+import (
+	"context"
+	"io"
+	"net"
+	"strings"
+)
+
+type memFile struct {
+	data string
+}
+
+func (m memFile) Open(ctx context.Context) (io.ReadCloser, error) {
+	return io.NopCloser(strings.NewReader(m.data)), nil
+}
+
+func (m memFile) String() string {
+	return "mem"
+}
+
+func NewMem(networks []*net.IPNet) (File) {
+	builder := strings.Builder{}
+
+	if len(networks) > 0 {
+		builder.WriteString(networks[0].String())
+	}
+
+	for i := 1; i < len(networks); i++ {
+		builder.WriteString("\n")
+		builder.WriteString(networks[i].String())
+	}
+
+	return memFile{
+		data:  builder.String(),
+	}
+}
diff --git a/ipblocklist/files/mem_test.go b/ipblocklist/files/mem_test.go
new file mode 100644
index 0000000..e3142b2
--- /dev/null
+++ b/ipblocklist/files/mem_test.go
@@ -0,0 +1,42 @@
+package files_test
+
+import (
+	"context"
+	"io"
+	"net"
+	"strings"
+	"testing"
+
+	"github.com/9seconds/mtg/v2/ipblocklist/files"
+	"github.com/stretchr/testify/suite"
+)
+
+type MemTestSuite struct {
+	suite.Suite
+}
+
+func (suite *MemTestSuite) TestOk() {
+	_, network1, _ := net.ParseCIDR("192.168.0.1/24")
+	_, network2, _ := net.ParseCIDR("2001:0db8:85a3:0000:0000:8a2e:0370:7334/36")
+
+	file := files.NewMem([]*net.IPNet{
+		network1,
+		network2,
+	})
+
+	reader, err := file.Open(context.Background())
+	suite.NoError(err)
+
+	data, err := io.ReadAll(reader)
+	suite.NoError(err)
+
+	strData := strings.TrimSpace(string(data))
+
+	suite.Contains(strData, "192.168.0.0/24")
+	suite.Contains(strData, "2001:db8:8000::/36")
+}
+
+func TestMem(t *testing.T) {
+	t.Parallel()
+	suite.Run(t, &MemTestSuite{})
+}