diff --git a/generate/generate_test.go b/generate/generate_test.go
new file mode 100644
index 0000000..ceb2ac9
--- /dev/null
+++ b/generate/generate_test.go
@@ -0,0 +1,236 @@
+package generate
+
+// import "fmt"
+import "strings"
+import "testing"
+import "git.tebibyte.media/sashakoshka/goparse"
+
+var testGenerateCorrect =
+`package protocol
+
+/* # Do not edit this package by hand!
+ * 
+ * This file was automatically generated by the Holanet PDL compiler. The
+ * source file is located at input.pdl
+ * Please edit that file instead, and re-compile it to this location.
+ *
+ * HOPP, TAPE, METADAPT, PDL/0 (c) 2025 holanet.xyz
+ */
+
+import "git.tebibyte.media/sashakoshka/hopp/tape"
+
+// Table is a KTV table with an undefined schema.
+type Table map[uint16] any
+
+// Message is any message that can be sent along this protocol.
+type Message interface {
+	tape.Encodable
+	tape.Decodable
+
+	// Method returns the method code of the message.
+	Method() uint16
+}
+
+// User represents the protocol data type User.
+type User struct {
+	Name string
+	Bio string
+	Followers uint32
+}
+
+// EncodeValue encodes the value of this type without the tag. The value is
+// encoded according to the parameters specified by the tag, if possible.
+func (this *User) EncodeValue(encoder *tape.Encoder) (n int, err error) {
+	nn, err := tape.WriteTableHeader(2)
+	n += nn; if err != nil { return n, err }
+	nn, err := encoder.WriteUint16(0x0000)
+	n += nn; if err != nil { return n, err }
+	nn, err := tape.WriteString(encoder, this.Name)
+	n += nn; if err != nil { return n, err }
+	nn, err := encoder.WriteUint16(0x0001)
+	n += nn; if err != nil { return n, err }
+	nn, err := tape.WriteString(encoder, this.Bio)
+	n += nn; if err != nil { return n, err }
+	return n, nil
+}
+
+// Decode replaces the data in this User with information from the decoder.
+func (this *User) Decode(decoder *tape.Decoder) (n int, err error) {
+	pull, nn, err := tape.ReadTableHeader(decoder)
+	n += nn; if err != nil { return n, err }
+
+	for {
+		key, tag, end, nn, err := pull()
+		n += nn; if err != nil { return n, err }
+		if end { break }
+
+		switch key {
+		case 0x0000:
+			value, nn, err := tape.ReadString(decoder)
+			n += nn; if err != nil { return n, err }
+			this.Name = value
+		case 0x0001:
+			value, nn, err := tape.ReadString(decoder)
+			n += nn; if err != nil { return n, err }
+			this.Bio = value 
+		}
+	}
+	
+	return n, nil
+}
+
+// MessageConnect represents the protocol message M0000 Connect.
+type MessageConnect struct {
+	Name string
+	Password string
+}
+
+// Method returns the method code, M0000.
+func (this *MessageConnect) Method() uint16 {
+	return 0x0000
+}
+
+// Encode encodes the message to the encoder.
+func (this *MessageConnect) Encode(encoder *tape.Encoder) (n int, err error) {
+	nn, err := tape.WriteTableHeader(2)
+	n += nn; if err != nil { return n, err }
+	nn, err := encoder.WriteUint16(0x0000)
+	n += nn; if err != nil { return n, err }
+	nn, err := tape.WriteString(encoder, this.Name)
+	n += nn; if err != nil { return n, err }
+	nn, err := encoder.WriteUint16(0x0001)
+	n += nn; if err != nil { return n, err }
+	nn, err := tape.WriteString(encoder, this.Password)
+	n += nn; if err != nil { return n, err }
+	return n, nil
+}
+
+// Decode replaces the data in this message with information from the decoder.
+func (this *MessageConnect) Decode(decoder *tape.Decoder) (n int, err error) {
+	pull, nn, err := tape.ReadTableHeader(decoder)
+	n += nn; if err != nil { return n, err }
+
+	for {
+		key, tag, end, nn, err := pull()
+		n += nn; if err != nil { return n, err }
+		if end { break }
+
+		switch key {
+		case 0x0000:
+			value, nn, err := tape.ReadString(decoder)
+			n += nn; if err != nil { return n, err }
+			this.Name = value
+		case 0x0001:
+			value, nn, err := tape.ReadString(decoder)
+			n += nn; if err != nil { return n, err }
+			this.Password = value 
+		}
+	}
+	
+	return n, nil
+}
+
+// MessageUserList represents the protocol message M0001 UserList.
+type MessageUserList struct {
+	Users []User
+}
+
+// Method returns the method code, M0001.
+func (this *MessageUserList) Method() uint16 {
+	return 0x0001
+}
+
+// TODO methods
+`
+
+func TestGenerate(test *testing.T) {
+	protocol := defaultProtocol()
+	protocol.Messages[0x0000] = Message {
+		Name: "Connect",
+		Type: TypeTableDefined {
+			Fields: map[uint16] Field {
+				0x0000: Field { Name: "Name",      Type: TypeNamed { Name: "String" } },
+				0x0001: Field { Name: "Password",  Type: TypeNamed { Name: "String" } },
+			},
+		},
+	}
+	protocol.Messages[0x0001] = Message {
+		Name: "UserList",
+		Type: TypeTableDefined {
+			Fields: map[uint16] Field {
+				0x0000: Field { Name: "Users",  Type: TypeArray { Element: TypeNamed { Name: "User" } } },
+			},
+		},
+	}
+	protocol.Types["User"] = TypeTableDefined {
+		Fields: map[uint16] Field {
+			0x0000: Field { Name: "Name",      Type: TypeNamed { Name: "String" } },
+			0x0001: Field { Name: "Bio",       Type: TypeNamed { Name: "String" } },
+			0x0002: Field { Name: "Followers", Type: TypeNamed { Name: "U32" } },
+		},
+	}
+
+	correct := testGenerateCorrect
+
+	builder := strings.Builder { }
+	generator := Generator { Output: &builder }
+	/* TODO test n: */ _, err := generator.Generate(&protocol)
+	if err != nil { test.Fatal(parse.Format(err)) }
+	got := builder.String()
+
+	test.Log("CORRECT:")
+	test.Log(correct)
+	test.Log("GOT:")
+	test.Log(got)
+
+	if correct != got {
+		test.Error("not equal")
+		for index := range min(len(correct), len(got)) {
+			if correct[index] == got[index] { continue }
+			test.Log("C:", correct[max(0, index - 8):min(len(correct), index + 8)])
+			test.Log("G:", got[max(0, index - 8):min(len(got), index + 8)])
+			break
+		}
+		test.FailNow()
+	}
+}
+
+func TestGenerateRun(test *testing.T) {
+	protocol := defaultProtocol()
+	protocol.Messages[0x0000] = Message {
+		Name: "Connect",
+		Type: TypeTableDefined {
+			Fields: map[uint16] Field {
+				0x0000: Field { Name: "Name",      Type: TypeNamed { Name: "String" } },
+				0x0001: Field { Name: "Password",  Type: TypeNamed { Name: "String" } },
+			},
+		},
+	}
+	protocol.Messages[0x0001] = Message {
+		Name: "UserList",
+		Type: TypeTableDefined {
+			Fields: map[uint16] Field {
+				0x0000: Field { Name: "Users",  Type: TypeArray { Element: TypeNamed { Name: "User" } } },
+			},
+		},
+	}
+	protocol.Types["User"] = TypeTableDefined {
+		Fields: map[uint16] Field {
+			0x0000: Field { Name: "Name",      Type: TypeNamed { Name: "String" } },
+			0x0001: Field { Name: "Bio",       Type: TypeNamed { Name: "String" } },
+			0x0002: Field { Name: "Followers", Type: TypeNamed { Name: "U32" } },
+		},
+	}
+	testGenerateRun(test, &protocol, `
+		// imports
+	`, `
+		// test case
+		messageConnect := MessageConnect {
+			Name: "rarity",
+			Password: "gems",
+		}
+		testEncode(
+			messageConnect,
+			0x0) // TODO
+	`)
+}