diff --git a/acceptance_testing.go b/acceptance_testing.go
index e00d3f5..ae31fe6 100644
--- a/acceptance_testing.go
+++ b/acceptance_testing.go
@@ -19,6 +19,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"maps"
 	"math/rand"
 	"reflect"
 	"regexp"
@@ -179,11 +180,11 @@ func (d ConfigurableAcceptanceTestDriver) Connector() Connector {
 }
 
 func (d ConfigurableAcceptanceTestDriver) SourceConfig(*testing.T) map[string]string {
-	return d.Config.SourceConfig
+	return maps.Clone(d.Config.SourceConfig)
 }
 
 func (d ConfigurableAcceptanceTestDriver) DestinationConfig(*testing.T) map[string]string {
-	return d.Config.DestinationConfig
+	return maps.Clone(d.Config.DestinationConfig)
 }
 
 func (d ConfigurableAcceptanceTestDriver) BeforeTest(t *testing.T) {
diff --git a/go.mod b/go.mod
index b798c15..c4ccc4e 100644
--- a/go.mod
+++ b/go.mod
@@ -5,6 +5,7 @@ go 1.20
 require (
 	github.com/Masterminds/sprig/v3 v3.2.3
 	github.com/conduitio/conduit-connector-protocol v0.5.0
+	github.com/goccy/go-json v0.10.2
 	github.com/golang/mock v1.6.0
 	github.com/google/uuid v1.3.0
 	github.com/jpillora/backoff v1.0.0
diff --git a/go.sum b/go.sum
index 85201cb..239132a 100644
--- a/go.sum
+++ b/go.sum
@@ -18,6 +18,8 @@ github.com/envoyproxy/go-control-plane v0.9.1-0.20191026205805-5f8ba28d4473/go.m
 github.com/envoyproxy/protoc-gen-validate v0.1.0/go.mod h1:iSmxcyjqTsJpI2R4NaDN7+kN2VEUnK/pcBlmesArF7c=
 github.com/fatih/color v1.7.0 h1:DkWD4oS2D8LGGgTQ6IvwJJXSL5Vp2ffcQg58nFV38Ys=
 github.com/fatih/color v1.7.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
+github.com/goccy/go-json v0.10.2 h1:CrxCmQqYDkv1z7lO7Wbh2HN93uovUHgrECaO5ZrCXAU=
+github.com/goccy/go-json v0.10.2/go.mod h1:6MelG93GURQebXPDq3khkgXZkazVtN9CRI+MGFi0w8I=
 github.com/godbus/dbus/v5 v5.0.4/go.mod h1:xhWf0FNVPg57R7Z0UbKHbJfkEywrmjJnf7w5xrFpKfA=
 github.com/golang/glog v0.0.0-20160126235308-23def4e6c14b/go.mod h1:SBH7ygxi8pfUlaOkMMuAQtPIUF8ecWP5IEl/CR7VP2Q=
 github.com/golang/mock v1.1.1/go.mod h1:oTYuIxOrZwtPieC+H1uAHpcLFnEyAGVDL/k47Jfbm0A=
diff --git a/record.go b/record.go
index 87b67c5..2af374e 100644
--- a/record.go
+++ b/record.go
@@ -18,12 +18,12 @@ package sdk
 
 import (
 	"context"
-	"encoding/json"
 	"fmt"
 	"strconv"
 	"strings"
 
 	"github.com/conduitio/conduit-connector-protocol/cpluginv1"
+	"github.com/goccy/go-json"
 )
 
 const (
diff --git a/record_formatter.go b/record_formatter.go
index 8663744..886da92 100644
--- a/record_formatter.go
+++ b/record_formatter.go
@@ -16,13 +16,13 @@ package sdk
 
 import (
 	"bytes"
-	"encoding/json"
 	"fmt"
 	"strings"
 	"text/template"
 
 	"github.com/Masterminds/sprig/v3"
 	"github.com/conduitio/conduit-connector-sdk/kafkaconnect"
+	"github.com/goccy/go-json"
 )
 
 // RecordFormatter is a type that can format a record to bytes. It's used in
diff --git a/record_formatter_test.go b/record_formatter_test.go
index 94d425d..a717146 100644
--- a/record_formatter_test.go
+++ b/record_formatter_test.go
@@ -21,6 +21,32 @@ import (
 	"github.com/matryer/is"
 )
 
+var (
+	encBytesSink []byte
+	encErrSink   error
+)
+
+func BenchmarkJSONEncoder(b *testing.B) {
+	rec := Record{
+		Position:  Position("foo"),
+		Operation: OperationCreate,
+		Metadata:  Metadata{MetadataConduitSourcePluginName: "example"},
+		Key:       RawData("bar"),
+		Payload: Change{
+			Before: nil,
+			After: StructuredData{
+				"foo": "bar",
+				"baz": "qux",
+			},
+		},
+	}
+
+	enc := JSONEncoder{}
+	for i := 0; i < b.N; i++ {
+		encBytesSink, encErrSink = enc.Encode(rec)
+	}
+}
+
 func TestOpenCDCConverter(t *testing.T) {
 	is := is.New(t)
 	var converter OpenCDCConverter
diff --git a/util.go b/util.go
index b55d9f5..ace28a5 100644
--- a/util.go
+++ b/util.go
@@ -16,6 +16,7 @@ package sdk
 
 import (
 	"fmt"
+	"reflect"
 	"strings"
 
 	"github.com/mitchellh/mapstructure"
@@ -81,6 +82,7 @@ func parseConfig(raw map[string]string, config interface{}) error {
 		WeaklyTypedInput: true,
 		Result:           &config,
 		DecodeHook: mapstructure.ComposeDecodeHookFunc(
+			emptyStringToZeroValueHookFunc(),
 			mapstructure.StringToTimeDurationHookFunc(),
 			mapstructure.StringToSliceHookFunc(","),
 		),
@@ -95,3 +97,15 @@ func parseConfig(raw map[string]string, config interface{}) error {
 	err = decoder.Decode(breakUpConfig(raw))
 	return err
 }
+
+func emptyStringToZeroValueHookFunc() mapstructure.DecodeHookFunc {
+	return func(
+		f reflect.Type,
+		t reflect.Type,
+		data interface{}) (interface{}, error) {
+		if f.Kind() != reflect.String || data != "" {
+			return data, nil
+		}
+		return reflect.New(t).Elem().Interface(), nil
+	}
+}
diff --git a/util_test.go b/util_test.go
index d809bce..87caf82 100644
--- a/util_test.go
+++ b/util_test.go
@@ -27,11 +27,13 @@ func TestParseConfig_Simple_Struct(t *testing.T) {
 	type Person struct {
 		Name string `json:"person_name"`
 		Age  int
+		Dur  time.Duration
 	}
 
 	input := map[string]string{
 		"person_name": "meroxa",
 		"age":         "91",
+		"dur":         "", // empty value should result in zero value
 	}
 	want := Person{
 		Name: "meroxa",