diff --git a/cli/wallet/validator.go b/cli/wallet/validator.go
index dd95c57b9..9426bd14c 100644
--- a/cli/wallet/validator.go
+++ b/cli/wallet/validator.go
@@ -10,12 +10,9 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
 	"github.com/nspcc-dev/neo-go/pkg/encoding/address"
-	"github.com/nspcc-dev/neo-go/pkg/io"
 	"github.com/nspcc-dev/neo-go/pkg/rpcclient"
-	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
 	"github.com/nspcc-dev/neo-go/pkg/util"
-	"github.com/nspcc-dev/neo-go/pkg/vm/emit"
-	"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
 	"github.com/nspcc-dev/neo-go/pkg/wallet"
 	"github.com/urfave/cli"
 )
@@ -122,10 +119,11 @@ func handleCandidate(ctx *cli.Context, method string, sysGas int64) error {
 	if err != nil {
 		return err
 	}
-	w := io.NewBufBinWriter()
-	emit.AppCall(w.BinWriter, neoContractHash, method, callflag.States, acc.PrivateKey().PublicKey().Bytes())
-	emit.Opcodes(w.BinWriter, opcode.ASSERT)
-	res, err := c.SignAndPushInvocationTx(w.Bytes(), acc, sysGas, gas, []rpcclient.SignerAccount{{
+	script, err := smartcontract.CreateCallWithAssertScript(neoContractHash, method, acc.PrivateKey().PublicKey().Bytes())
+	if err != nil {
+		return cli.NewExitError(err, 1)
+	}
+	res, err := c.SignAndPushInvocationTx(script, acc, sysGas, gas, []rpcclient.SignerAccount{{
 		Signer: transaction.Signer{
 			Account: acc.Contract.ScriptHash(),
 			Scopes:  transaction.CalledByEntry,
@@ -182,11 +180,11 @@ func handleVote(ctx *cli.Context) error {
 	if err != nil {
 		return cli.NewExitError(err, 1)
 	}
-	w := io.NewBufBinWriter()
-	emit.AppCall(w.BinWriter, neoContractHash, "vote", callflag.States, addr.BytesBE(), pubArg)
-	emit.Opcodes(w.BinWriter, opcode.ASSERT)
-
-	res, err := c.SignAndPushInvocationTx(w.Bytes(), acc, -1, gas, []rpcclient.SignerAccount{{
+	script, err := smartcontract.CreateCallWithAssertScript(neoContractHash, "vote", addr.BytesBE(), pubArg)
+	if err != nil {
+		return cli.NewExitError(err, 1)
+	}
+	res, err := c.SignAndPushInvocationTx(script, acc, -1, gas, []rpcclient.SignerAccount{{
 		Signer: transaction.Signer{
 			Account: acc.Contract.ScriptHash(),
 			Scopes:  transaction.CalledByEntry,
diff --git a/internal/testchain/transaction.go b/internal/testchain/transaction.go
index 3c5aac449..2e05a804c 100644
--- a/internal/testchain/transaction.go
+++ b/internal/testchain/transaction.go
@@ -6,7 +6,7 @@ import (
 	gio "io"
 	"strings"
 
-	"github.com/nspcc-dev/neo-go/cli/smartcontract"
+	clisc "github.com/nspcc-dev/neo-go/cli/smartcontract"
 	"github.com/nspcc-dev/neo-go/pkg/compiler"
 	"github.com/nspcc-dev/neo-go/pkg/config"
 	"github.com/nspcc-dev/neo-go/pkg/core/block"
@@ -16,11 +16,9 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
 	"github.com/nspcc-dev/neo-go/pkg/io"
-	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest"
 	"github.com/nspcc-dev/neo-go/pkg/util"
-	"github.com/nspcc-dev/neo-go/pkg/vm/emit"
-	"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
 )
 
 // Ledger is an interface that abstracts the implementation of the blockchain.
@@ -42,14 +40,11 @@ var (
 // NewTransferFromOwner returns a transaction transferring funds from NEO and GAS owner.
 func NewTransferFromOwner(bc Ledger, contractHash, to util.Uint160, amount int64,
 	nonce, validUntil uint32) (*transaction.Transaction, error) {
-	w := io.NewBufBinWriter()
-	emit.AppCall(w.BinWriter, contractHash, "transfer", callflag.All, ownerHash, to, amount, nil)
-	emit.Opcodes(w.BinWriter, opcode.ASSERT)
-	if w.Err != nil {
-		return nil, w.Err
+	script, err := smartcontract.CreateCallWithAssertScript(contractHash, "transfer", ownerHash, to, amount, nil)
+	if err != nil {
+		return nil, err
 	}
 
-	script := w.Bytes()
 	tx := transaction.New(script, 11000000)
 	tx.ValidUntilBlock = validUntil
 	tx.Nonce = nonce
@@ -74,7 +69,7 @@ func NewDeployTx(bc Ledger, name string, sender util.Uint160, r gio.Reader, conf
 		NoEventsCheck:   true,
 	}
 	if confFile != nil {
-		conf, err := smartcontract.ParseContractConfig(*confFile)
+		conf, err := clisc.ParseContractConfig(*confFile)
 		if err != nil {
 			return nil, util.Uint160{}, nil, fmt.Errorf("failed to parse configuration: %w", err)
 		}
@@ -108,13 +103,12 @@ func NewDeployTx(bc Ledger, name string, sender util.Uint160, r gio.Reader, conf
 	if err != nil {
 		return nil, util.Uint160{}, nil, err
 	}
-	buf := io.NewBufBinWriter()
-	emit.AppCall(buf.BinWriter, bc.ManagementContractHash(), "deploy", callflag.All, neb, rawManifest)
-	if buf.Err != nil {
-		return nil, util.Uint160{}, nil, buf.Err
+	script, err := smartcontract.CreateCallScript(bc.ManagementContractHash(), "deploy", neb, rawManifest)
+	if err != nil {
+		return nil, util.Uint160{}, nil, err
 	}
 
-	tx := transaction.New(buf.Bytes(), 100*native.GASFactor)
+	tx := transaction.New(script, 100*native.GASFactor)
 	tx.Signers = []transaction.Signer{{Account: sender}}
 	h := state.CreateContractHash(tx.Sender(), ne.Checksum, m.Name)
 
diff --git a/pkg/consensus/consensus_test.go b/pkg/consensus/consensus_test.go
index a49af9759..754bb74b0 100644
--- a/pkg/consensus/consensus_test.go
+++ b/pkg/consensus/consensus_test.go
@@ -22,7 +22,6 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/io"
 	npayload "github.com/nspcc-dev/neo-go/pkg/network/payload"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
-	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
 	"github.com/nspcc-dev/neo-go/pkg/util"
 	"github.com/nspcc-dev/neo-go/pkg/vm/emit"
 	"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
@@ -55,16 +54,16 @@ func initServiceNextConsensus(t *testing.T, newAcc *wallet.Account, offset uint3
 	newPriv := newAcc.PrivateKey()
 
 	// Transfer funds to new validator.
-	w := io.NewBufBinWriter()
-	emit.AppCall(w.BinWriter, bc.GoverningTokenHash(), "transfer", callflag.All,
+	b := smartcontract.NewBuilder()
+	b.InvokeWithAssert(bc.GoverningTokenHash(), "transfer",
 		acc.Contract.ScriptHash().BytesBE(), newPriv.GetScriptHash().BytesBE(), int64(native.NEOTotalSupply), nil)
-	emit.Opcodes(w.BinWriter, opcode.ASSERT)
-	emit.AppCall(w.BinWriter, bc.UtilityTokenHash(), "transfer", callflag.All,
-		acc.Contract.ScriptHash().BytesBE(), newPriv.GetScriptHash().BytesBE(), int64(10000_000_000_000), nil)
-	emit.Opcodes(w.BinWriter, opcode.ASSERT)
-	require.NoError(t, w.Err)
 
-	tx := transaction.New(w.Bytes(), 21_000_000)
+	b.InvokeWithAssert(bc.UtilityTokenHash(), "transfer",
+		acc.Contract.ScriptHash().BytesBE(), newPriv.GetScriptHash().BytesBE(), int64(10000_000_000_000), nil)
+	script, err := b.Script()
+	require.NoError(t, err)
+
+	tx := transaction.New(script, 21_000_000)
 	tx.ValidUntilBlock = bc.BlockHeight() + 1
 	tx.NetworkFee = 10_000_000
 	tx.Signers = []transaction.Signer{{Scopes: transaction.Global, Account: acc.Contract.ScriptHash()}}
@@ -75,11 +74,12 @@ func initServiceNextConsensus(t *testing.T, newAcc *wallet.Account, offset uint3
 	srv.dbft.Start()
 
 	// Register new candidate.
-	w.Reset()
-	emit.AppCall(w.BinWriter, bc.GoverningTokenHash(), "registerCandidate", callflag.All, newPriv.PublicKey().Bytes())
-	require.NoError(t, w.Err)
+	b.Reset()
+	b.InvokeWithAssert(bc.GoverningTokenHash(), "registerCandidate", newPriv.PublicKey().Bytes())
+	script, err = b.Script()
+	require.NoError(t, err)
 
-	tx = transaction.New(w.Bytes(), 1001_00000000)
+	tx = transaction.New(script, 1001_00000000)
 	tx.ValidUntilBlock = bc.BlockHeight() + 1
 	tx.NetworkFee = 20_000_000
 	tx.Signers = []transaction.Signer{{Scopes: transaction.Global, Account: newPriv.GetScriptHash()}}
@@ -94,13 +94,13 @@ func initServiceNextConsensus(t *testing.T, newAcc *wallet.Account, offset uint3
 	}
 
 	// Vote for new candidate.
-	w.Reset()
-	emit.AppCall(w.BinWriter, bc.GoverningTokenHash(), "vote", callflag.All,
+	b.Reset()
+	b.InvokeWithAssert(bc.GoverningTokenHash(), "vote",
 		newPriv.GetScriptHash(), newPriv.PublicKey().Bytes())
-	emit.Opcodes(w.BinWriter, opcode.ASSERT)
-	require.NoError(t, w.Err)
+	script, err = b.Script()
+	require.NoError(t, err)
 
-	tx = transaction.New(w.Bytes(), 20_000_000)
+	tx = transaction.New(script, 20_000_000)
 	tx.ValidUntilBlock = bc.BlockHeight() + 1
 	tx.NetworkFee = 20_000_000
 	tx.Signers = []transaction.Signer{{Scopes: transaction.Global, Account: newPriv.GetScriptHash()}}
diff --git a/pkg/core/bench_test.go b/pkg/core/bench_test.go
index 2e6415a10..2885487b7 100644
--- a/pkg/core/bench_test.go
+++ b/pkg/core/bench_test.go
@@ -14,12 +14,9 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/core/storage/dbconfig"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
-	"github.com/nspcc-dev/neo-go/pkg/io"
 	"github.com/nspcc-dev/neo-go/pkg/neotest"
 	"github.com/nspcc-dev/neo-go/pkg/neotest/chain"
-	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
-	"github.com/nspcc-dev/neo-go/pkg/vm/emit"
-	"github.com/nspcc-dev/neo-go/pkg/vm/opcode"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
 	"github.com/nspcc-dev/neo-go/pkg/wallet"
 	"github.com/stretchr/testify/require"
 )
@@ -96,13 +93,12 @@ func benchmarkForEachNEP17Transfer(t *testing.B, ps storage.Store, startFromBloc
 	from := e.Validator.ScriptHash()
 
 	for j := 0; j < chainHeight; j++ {
-		w := io.NewBufBinWriter()
+		b := smartcontract.NewBuilder()
 		for i := 0; i < transfersPerBlock; i++ {
-			emit.AppCall(w.BinWriter, gasHash, "transfer", callflag.All, from, acc, 1, nil)
-			emit.Opcodes(w.BinWriter, opcode.ASSERT)
+			b.InvokeWithAssert(gasHash, "transfer", from, acc, 1, nil)
 		}
-		require.NoError(t, w.Err)
-		script := w.Bytes()
+		script, err := b.Script()
+		require.NoError(t, err)
 		tx := transaction.New(script, int64(1100_0000*transfersPerBlock))
 		tx.NetworkFee = 1_0000_000
 		tx.ValidUntilBlock = bc.BlockHeight() + 1
diff --git a/pkg/core/interop/runtime/ext_test.go b/pkg/core/interop/runtime/ext_test.go
index bc262fe4a..43e5fff56 100644
--- a/pkg/core/interop/runtime/ext_test.go
+++ b/pkg/core/interop/runtime/ext_test.go
@@ -26,6 +26,7 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/io"
 	"github.com/nspcc-dev/neo-go/pkg/neotest"
 	"github.com/nspcc-dev/neo-go/pkg/neotest/chain"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/nef"
@@ -424,9 +425,9 @@ func TestGetInvocationCounter(t *testing.T) {
 		require.EqualValues(t, 42, v.Estack().Pop().BigInt().Int64())
 	})
 	t.Run("Contract", func(t *testing.T) {
-		w := io.NewBufBinWriter()
-		emit.AppCall(w.BinWriter, cs.Hash, "invocCounter", callflag.All)
-		v.LoadWithFlags(w.Bytes(), callflag.All)
+		script, err := smartcontract.CreateCallScript(cs.Hash, "invocCounter")
+		require.NoError(t, err)
+		v.LoadWithFlags(script, callflag.All)
 		require.NoError(t, v.Run())
 		require.EqualValues(t, 1, v.Estack().Pop().BigInt().Int64())
 	})
diff --git a/pkg/core/native/native_test/oracle_test.go b/pkg/core/native/native_test/oracle_test.go
index 4aafc7175..754add6d1 100644
--- a/pkg/core/native/native_test/oracle_test.go
+++ b/pkg/core/native/native_test/oracle_test.go
@@ -14,10 +14,8 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/core/native/noderoles"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
-	"github.com/nspcc-dev/neo-go/pkg/io"
 	"github.com/nspcc-dev/neo-go/pkg/neotest"
-	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
-	"github.com/nspcc-dev/neo-go/pkg/vm/emit"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
 	"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
 	"github.com/stretchr/testify/require"
 )
@@ -81,11 +79,9 @@ func TestOracle_Request(t *testing.T) {
 
 	// Finish.
 	prepareResponseTx := func(t *testing.T, requestID uint64) *transaction.Transaction {
-		w := io.NewBufBinWriter()
-		emit.AppCall(w.BinWriter, oracleCommitteeInvoker.Hash, "finish", callflag.All)
-		require.NoError(t, w.Err)
+		script, err := smartcontract.CreateCallScript(oracleCommitteeInvoker.Hash, "finish")
+		require.NoError(t, err)
 
-		script := w.Bytes()
 		tx := transaction.New(script, 1000_0000)
 		tx.Nonce = neotest.Nonce()
 		tx.ValidUntilBlock = e.Chain.BlockHeight() + 1
diff --git a/pkg/core/native/oracle.go b/pkg/core/native/oracle.go
index 8f99fd936..a31eb929d 100644
--- a/pkg/core/native/oracle.go
+++ b/pkg/core/native/oracle.go
@@ -20,13 +20,11 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/crypto/hash"
 	"github.com/nspcc-dev/neo-go/pkg/crypto/keys"
 	"github.com/nspcc-dev/neo-go/pkg/encoding/bigint"
-	"github.com/nspcc-dev/neo-go/pkg/io"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/manifest"
 	"github.com/nspcc-dev/neo-go/pkg/util"
 	"github.com/nspcc-dev/neo-go/pkg/util/slice"
-	"github.com/nspcc-dev/neo-go/pkg/vm/emit"
 	"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
 )
 
@@ -556,10 +554,9 @@ func (o *Oracle) updateCache(d *dao.Simple) error {
 // CreateOracleResponseScript returns a script that is used to create the native Oracle
 // response.
 func CreateOracleResponseScript(nativeOracleHash util.Uint160) []byte {
-	w := io.NewBufBinWriter()
-	emit.AppCall(w.BinWriter, nativeOracleHash, "finish", callflag.All)
-	if w.Err != nil {
-		panic(fmt.Errorf("failed to create Oracle response script: %w", w.Err))
+	script, err := smartcontract.CreateCallScript(nativeOracleHash, "finish")
+	if err != nil {
+		panic(fmt.Errorf("failed to create Oracle response script: %w", err))
 	}
-	return w.Bytes()
+	return script
 }
diff --git a/pkg/neotest/basic.go b/pkg/neotest/basic.go
index 7d85882f4..a115aa7a4 100644
--- a/pkg/neotest/basic.go
+++ b/pkg/neotest/basic.go
@@ -16,11 +16,11 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/core/state"
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/io"
+	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract/trigger"
 	"github.com/nspcc-dev/neo-go/pkg/util"
 	"github.com/nspcc-dev/neo-go/pkg/vm"
-	"github.com/nspcc-dev/neo-go/pkg/vm/emit"
 	"github.com/nspcc-dev/neo-go/pkg/vm/stackitem"
 	"github.com/nspcc-dev/neo-go/pkg/vm/vmstate"
 	"github.com/nspcc-dev/neo-go/pkg/wallet"
@@ -81,11 +81,9 @@ func (e *Executor) NativeID(t testing.TB, name string) int32 {
 
 // NewUnsignedTx creates a new unsigned transaction which invokes the method of the contract with the hash.
 func (e *Executor) NewUnsignedTx(t testing.TB, hash util.Uint160, method string, args ...interface{}) *transaction.Transaction {
-	w := io.NewBufBinWriter()
-	emit.AppCall(w.BinWriter, hash, method, callflag.All, args...)
-	require.NoError(t, w.Err)
+	script, err := smartcontract.CreateCallScript(hash, method, args...)
+	require.NoError(t, err)
 
-	script := w.Bytes()
 	tx := transaction.New(script, 0)
 	tx.Nonce = Nonce()
 	tx.ValidUntilBlock = e.Chain.BlockHeight() + 1
@@ -266,11 +264,10 @@ func NewDeployTxBy(t testing.TB, bc *core.Blockchain, signer Signer, c *Contract
 	neb, err := c.NEF.Bytes()
 	require.NoError(t, err)
 
-	buf := io.NewBufBinWriter()
-	emit.AppCall(buf.BinWriter, bc.ManagementContractHash(), "deploy", callflag.All, neb, rawManifest, data)
-	require.NoError(t, buf.Err)
+	script, err := smartcontract.CreateCallScript(bc.ManagementContractHash(), "deploy", neb, rawManifest, data)
+	require.NoError(t, err)
 
-	tx := transaction.New(buf.Bytes(), 100*native.GASFactor)
+	tx := transaction.New(script, 100*native.GASFactor)
 	tx.Nonce = Nonce()
 	tx.ValidUntilBlock = bc.BlockHeight() + 1
 	tx.Signers = []transaction.Signer{{
diff --git a/pkg/smartcontract/entry.go b/pkg/smartcontract/entry.go
index 5423495ef..a3fb44262 100644
--- a/pkg/smartcontract/entry.go
+++ b/pkg/smartcontract/entry.go
@@ -77,6 +77,15 @@ func CreateCallAndUnwrapIteratorScript(contract util.Uint160, operation string,
 	return bytes, nil
 }
 
+// CreateCallScript returns a script that calls contract's method with
+// the specified parameters. Whatever this method returns remains on the stack.
+// See also (*Builder).InvokeMethod.
+func CreateCallScript(contract util.Uint160, method string, params ...interface{}) ([]byte, error) {
+	b := NewBuilder()
+	b.InvokeMethod(contract, method, params...)
+	return b.Script()
+}
+
 // CreateCallWithAssertScript returns a script that calls contract's method with
 // the specified parameters expecting a Boolean value to be return that then is
 // used for ASSERT. See also (*Builder).InvokeWithAssert.
diff --git a/scripts/gendump/main.go b/scripts/gendump/main.go
index ef7079413..6f79ff917 100644
--- a/scripts/gendump/main.go
+++ b/scripts/gendump/main.go
@@ -20,8 +20,6 @@ import (
 	"github.com/nspcc-dev/neo-go/pkg/core/transaction"
 	"github.com/nspcc-dev/neo-go/pkg/io"
 	"github.com/nspcc-dev/neo-go/pkg/smartcontract"
-	"github.com/nspcc-dev/neo-go/pkg/smartcontract/callflag"
-	"github.com/nspcc-dev/neo-go/pkg/vm/emit"
 	"github.com/nspcc-dev/neo-go/pkg/wallet"
 	"go.uber.org/zap"
 	"go.uber.org/zap/zapcore"
@@ -99,11 +97,10 @@ func main() {
 			_, err = rand.Read(value)
 			handleError("can't get random data for value", err)
 
-			w := io.NewBufBinWriter()
-			emit.AppCall(w.BinWriter, contractHash, "put", callflag.All, key, value)
-			handleError("can't create transaction", w.Err)
+			script, err := smartcontract.CreateCallScript(contractHash, "put", key, value)
+			handleError("can't create transaction", err)
 
-			tx := transaction.New(w.Bytes(), 4_040_000)
+			tx := transaction.New(script, 4_040_000)
 			tx.ValidUntilBlock = i + 1
 			tx.NetworkFee = 4_000_000
 			tx.Nonce = nonce