diff --git a/go.mod b/go.mod
index 7d1a2225..450fde7d 100644
--- a/go.mod
+++ b/go.mod
@@ -6,6 +6,7 @@ require (
 	github.com/Masterminds/sprig/v3 v3.3.0
 	github.com/aws/aws-sdk-go v1.55.5
 	github.com/dchest/siphash v1.2.3
+	github.com/expr-lang/expr v1.16.7
 	github.com/ggwhite/go-masker v1.1.0
 	github.com/go-faker/faker/v4 v4.5.0
 	github.com/google/uuid v1.6.0
diff --git a/go.sum b/go.sum
index b90501b2..393984a4 100644
--- a/go.sum
+++ b/go.sum
@@ -16,6 +16,8 @@ github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc h1:U9qPSI2PIWSS1
 github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dchest/siphash v1.2.3 h1:QXwFc8cFOR2dSa/gE6o/HokBMWtLUaNDVd+22aKHeEA=
 github.com/dchest/siphash v1.2.3/go.mod h1:0NvQU092bT0ipiFN++/rXm69QG9tVxLAlQHIXMPAkHc=
+github.com/expr-lang/expr v1.16.7 h1:gCIiHt5ODA0xIaDbD0DPKyZpM9Drph3b3lolYAYq2Kw=
+github.com/expr-lang/expr v1.16.7/go.mod h1:8/vRC7+7HBzESEqt5kKpYXxrxkr31SaO8r40VO/1IT4=
 github.com/frankban/quicktest v1.14.6 h1:7Xjx+VpznH+oBnejlPUj8oUpdxnVs4f8XU8WnHkI4W8=
 github.com/frankban/quicktest v1.14.6/go.mod h1:4ptaffx2x8+WTWXmUCuVU6aPUX1/Mz7zb5vbUoiM6w0=
 github.com/fsnotify/fsnotify v1.7.0 h1:8JEhPFa5W2WU7YfeZzPNqzMP6Lwt7L2715Ggo0nosvA=
diff --git a/internal/db/postgres/context/table.go b/internal/db/postgres/context/table.go
index 321f5260..808b810d 100644
--- a/internal/db/postgres/context/table.go
+++ b/internal/db/postgres/context/table.go
@@ -124,7 +124,7 @@ func validateAndBuildTablesConfig(
 			// InitTransformation toolkit
 			if len(tableCfg.Transformers) > 0 {
 				for _, tc := range tableCfg.Transformers {
-					transformer, initWarnings, err := initTransformer(ctx, driver, tc, registry, types)
+					transformer, initWarnings, err := initTransformer(ctx, driver, tc, registry)
 					if len(initWarnings) > 0 {
 						for _, w := range initWarnings {
 							// Enriching the tables context into meta
diff --git a/internal/db/postgres/context/transformers.go b/internal/db/postgres/context/transformers.go
index 0c611ad5..b32d53d0 100644
--- a/internal/db/postgres/context/transformers.go
+++ b/internal/db/postgres/context/transformers.go
@@ -27,8 +27,8 @@ func initTransformer(
 	ctx context.Context, d *toolkit.Driver,
 	c *domains.TransformerConfig,
 	r *transformersUtils.TransformerRegistry,
-	types []*toolkit.Type,
 ) (*transformersUtils.TransformerContext, toolkit.ValidationWarnings, error) {
+	// TODO: Create
 	var totalWarnings toolkit.ValidationWarnings
 	td, ok := r.Get(c.Name)
 	if !ok {
@@ -42,7 +42,7 @@ func initTransformer(
 			}))
 		return nil, totalWarnings, nil
 	}
-	transformer, warnings, err := td.Instance(ctx, d, c.Params, c.DynamicParams)
+	transformer, warnings, err := td.Instance(ctx, d, c.Params, c.DynamicParams, c.When)
 	if err != nil {
 		return nil, nil, fmt.Errorf("unable to init transformer: %w", err)
 	}
diff --git a/internal/db/postgres/dumpers/transformation_pipeline.go b/internal/db/postgres/dumpers/transformation_pipeline.go
index f083253e..0d185018 100644
--- a/internal/db/postgres/dumpers/transformation_pipeline.go
+++ b/internal/db/postgres/dumpers/transformation_pipeline.go
@@ -132,7 +132,15 @@ func (tp *TransformationPipeline) Init(ctx context.Context) error {
 
 func (tp *TransformationPipeline) TransformSync(ctx context.Context, r *toolkit.Record) (*toolkit.Record, error) {
 	var err error
+	var needTransform bool
 	for _, t := range tp.table.TransformersContext {
+		needTransform, err = t.EvaluateWhen()
+		if err != nil {
+			return nil, NewDumpError(tp.table.Schema, tp.table.Name, tp.line, fmt.Errorf("error evaluating when condition: %w", err))
+		}
+		if !needTransform {
+			continue
+		}
 		_, err = t.Transformer.Transform(ctx, r)
 		if err != nil {
 			return nil, NewDumpError(tp.table.Schema, tp.table.Name, tp.line, err)
diff --git a/internal/db/postgres/transformers/column_context.go b/internal/db/postgres/transformers/column_context.go
index e522e69a..dbc6f455 100644
--- a/internal/db/postgres/transformers/column_context.go
+++ b/internal/db/postgres/transformers/column_context.go
@@ -49,7 +49,7 @@ func (cc *ColumnContext) GetValue() (any, error) {
 }
 
 func (cc *ColumnContext) GetRawValue() (any, error) {
-	return cc.rc.GetRawColumnValue(cc.columnName)
+	return cc.rc.GetColumnRawValue(cc.columnName)
 }
 
 func (cc *ColumnContext) GetColumnValue(name string) (any, error) {
@@ -57,7 +57,7 @@ func (cc *ColumnContext) GetColumnValue(name string) (any, error) {
 }
 
 func (cc *ColumnContext) GetColumnRawValue(name string) (any, error) {
-	return cc.rc.GetRawColumnValue(name)
+	return cc.rc.GetColumnRawValue(name)
 }
 
 func (cc *ColumnContext) EncodeValue(v any) (any, error) {
diff --git a/internal/db/postgres/transformers/dict_test.go b/internal/db/postgres/transformers/dict_test.go
index 8eec7890..d1744248 100644
--- a/internal/db/postgres/transformers/dict_test.go
+++ b/internal/db/postgres/transformers/dict_test.go
@@ -41,6 +41,7 @@ func TestDictTransformer_Transform_with_fail(t *testing.T) {
 		context.Background(),
 		driver, params,
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	require.Empty(t, warnings)
@@ -85,6 +86,7 @@ func TestDictTransformer_Transform_validation_error(t *testing.T) {
 		context.Background(),
 		driver, params,
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	require.NotEmpty(t, warnings)
@@ -101,6 +103,7 @@ func TestDictTransformer_Transform_validation_error(t *testing.T) {
 		context.Background(),
 		driver, params,
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	require.NotEmpty(t, warnings)
@@ -121,6 +124,7 @@ func TestDictTransformer_Transform_error_not_matched(t *testing.T) {
 		context.Background(),
 		driver, params,
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	require.Empty(t, warnings)
@@ -149,6 +153,7 @@ func TestDictTransformer_Transform_use_default(t *testing.T) {
 		context.Background(),
 		driver, params,
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	require.Empty(t, warnings)
@@ -180,6 +185,7 @@ func TestDictTransformer_Transform_with_int_values(t *testing.T) {
 		context.Background(),
 		driver, params,
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/email.go b/internal/db/postgres/transformers/email.go
index 3ec79f3c..815dcb81 100644
--- a/internal/db/postgres/transformers/email.go
+++ b/internal/db/postgres/transformers/email.go
@@ -92,7 +92,7 @@ type EmailTransformer struct {
 	originalDomain           []byte
 	randomBytesBuf           []byte
 	hexEncodedRandomBytesBuf []byte
-	rrctx                    *RoRecordContext
+	rctx                     *toolkit.RecordContext
 }
 
 func NewEmailTransformer(ctx context.Context, driver *toolkit.Driver, parameters map[string]toolkit.Parameterizer) (utils.Transformer, toolkit.ValidationWarnings, error) {
@@ -142,7 +142,7 @@ func NewEmailTransformer(ctx context.Context, driver *toolkit.Driver, parameters
 		return nil, nil, fmt.Errorf(`unable to scan "domain_part_template" param: %w`, err)
 	}
 
-	rrctx := NewRoRecordContext()
+	rrctx := toolkit.NewRecordContext()
 	funcMap := toolkit.FuncMap()
 	if localPartTemplate != "" || domainTemplate != "" {
 		for _, c := range driver.Table.Columns {
@@ -208,8 +208,8 @@ func NewEmailTransformer(ctx context.Context, driver *toolkit.Driver, parameters
 		domainTemplate:           domainTmpl,
 		validate:                 validate,
 		buf:                      bytes.NewBuffer(nil),
-		hexEncodedRandomBytesBuf: make([]byte, hex.EncodedLen(maxLength)),
-		rrctx:                    rrctx,
+		hexEncodedRandomBytesBuf: make([]byte, hex.EncodedLen(emailTransformerGeneratorSize)),
+		rctx:                     rrctx,
 	}, nil, nil
 }
 
@@ -264,7 +264,7 @@ func (rit *EmailTransformer) setupTemplateContext(originalEmail []byte, r *toolk
 	if rit.localPartTemplate == nil && rit.domainTemplate == nil && !rit.keepOriginalDomain {
 		return nil
 	}
-	rit.rrctx.setRecord(r)
+	rit.rctx.SetRecord(r)
 
 	originalLocalPart, originalDomain, err := EmailParse(originalEmail)
 	if err != nil {
diff --git a/internal/db/postgres/transformers/hash_test.go b/internal/db/postgres/transformers/hash_test.go
index 15ed8a71..f3c6151c 100644
--- a/internal/db/postgres/transformers/hash_test.go
+++ b/internal/db/postgres/transformers/hash_test.go
@@ -77,6 +77,7 @@ func TestHashTransformer_Transform_all_functions(t *testing.T) {
 				context.Background(),
 				driver, tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
@@ -154,6 +155,7 @@ func TestHashTransformer_Transform_length_truncation(t *testing.T) {
 		context.Background(),
 		driver, params,
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	require.Empty(t, warnings)
@@ -184,6 +186,7 @@ func TestHashTransformer_Transform_multiple_iterations(t *testing.T) {
 		context.Background(),
 		driver, params,
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/json_context.go b/internal/db/postgres/transformers/json_context.go
index 2e36596f..f26862c3 100644
--- a/internal/db/postgres/transformers/json_context.go
+++ b/internal/db/postgres/transformers/json_context.go
@@ -47,7 +47,7 @@ func (jc *JsonContext) GetColumnValue(name string) (any, error) {
 }
 
 func (jc *JsonContext) GetColumnRawValue(name string) (any, error) {
-	return jc.rc.GetRawColumnValue(name)
+	return jc.rc.GetColumnRawValue(name)
 }
 
 func (jc *JsonContext) EncodeValueByColumn(name string, v any) (any, error) {
diff --git a/internal/db/postgres/transformers/json_test.go b/internal/db/postgres/transformers/json_test.go
index cef9bd33..7a23b10b 100644
--- a/internal/db/postgres/transformers/json_test.go
+++ b/internal/db/postgres/transformers/json_test.go
@@ -44,6 +44,7 @@ func TestJsonTransformer_Transform(t *testing.T) {
 			]`),
 		},
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	assert.Empty(t, warnings)
@@ -86,6 +87,7 @@ func TestJsonTransformer_Transform_with_template(t *testing.T) {
 			"operations": opsData,
 		},
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	assert.Empty(t, warnings)
@@ -130,6 +132,7 @@ func TestJsonTransformer_Transform_null(t *testing.T) {
 			"keep_null":  toolkit.ParamsValue("false"),
 		},
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	assert.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/masking_test.go b/internal/db/postgres/transformers/masking_test.go
index 56b17b21..89d6673a 100644
--- a/internal/db/postgres/transformers/masking_test.go
+++ b/internal/db/postgres/transformers/masking_test.go
@@ -79,6 +79,7 @@ func TestMaskingTransformer_Transform(t *testing.T) {
 				context.Background(),
 				driver, tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
@@ -109,6 +110,7 @@ func TestMaskingTransformer_type_validation(t *testing.T) {
 			"type":   toolkit.ParamsValue("unknown"),
 		},
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	assert.Len(t, warnings, 1)
diff --git a/internal/db/postgres/transformers/noise_date_test.go b/internal/db/postgres/transformers/noise_date_test.go
index af84f361..35cd2ecc 100644
--- a/internal/db/postgres/transformers/noise_date_test.go
+++ b/internal/db/postgres/transformers/noise_date_test.go
@@ -118,6 +118,7 @@ func TestNoiseDateTransformer_Transform(t *testing.T) {
 				context.Background(),
 				driver, tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/noise_float_test.go b/internal/db/postgres/transformers/noise_float_test.go
index 9024d1a2..1c705c9a 100644
--- a/internal/db/postgres/transformers/noise_float_test.go
+++ b/internal/db/postgres/transformers/noise_float_test.go
@@ -131,6 +131,7 @@ func TestNoiseFloatTransformer_Transform(t *testing.T) {
 				driver,
 				tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/noise_int_test.go b/internal/db/postgres/transformers/noise_int_test.go
index 012ffadd..0a6adc6b 100644
--- a/internal/db/postgres/transformers/noise_int_test.go
+++ b/internal/db/postgres/transformers/noise_int_test.go
@@ -104,6 +104,7 @@ func TestNoiseIntTransformer_Transform(t *testing.T) {
 				context.Background(),
 				driver, tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/noise_numeric_test.go b/internal/db/postgres/transformers/noise_numeric_test.go
index 61600277..5daf460f 100644
--- a/internal/db/postgres/transformers/noise_numeric_test.go
+++ b/internal/db/postgres/transformers/noise_numeric_test.go
@@ -121,6 +121,7 @@ func TestNoiseNumericTransformer_Transform(t *testing.T) {
 				driver,
 				tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/random_bool_test.go b/internal/db/postgres/transformers/random_bool_test.go
index b76849fa..22463753 100644
--- a/internal/db/postgres/transformers/random_bool_test.go
+++ b/internal/db/postgres/transformers/random_bool_test.go
@@ -67,6 +67,7 @@ func TestRandomBoolTransformer_Transform(t *testing.T) {
 				driver,
 				tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/random_choice_test.go b/internal/db/postgres/transformers/random_choice_test.go
index cc4bd721..77b9b5fb 100644
--- a/internal/db/postgres/transformers/random_choice_test.go
+++ b/internal/db/postgres/transformers/random_choice_test.go
@@ -26,6 +26,7 @@ func TestRandomChoiceTransformer_Transform_with_fail(t *testing.T) {
 		context.Background(),
 		driver, params,
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	require.Empty(t, warnings)
@@ -57,6 +58,7 @@ func TestRandomChoiceTransformer_Transform_validation_error(t *testing.T) {
 		context.Background(),
 		driver, params,
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	require.NotEmpty(t, warnings)
@@ -78,6 +80,7 @@ func TestRandomChoiceTransformer_Transform_json(t *testing.T) {
 		context.Background(),
 		driver, params,
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/random_date_test.go b/internal/db/postgres/transformers/random_date_test.go
index 91ef1297..5409d264 100644
--- a/internal/db/postgres/transformers/random_date_test.go
+++ b/internal/db/postgres/transformers/random_date_test.go
@@ -116,6 +116,7 @@ func TestTimestampTransformer_Transform(t *testing.T) {
 				context.Background(),
 				driver, tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/random_float_test.go b/internal/db/postgres/transformers/random_float_test.go
index dfd7cb7a..cc6e909a 100644
--- a/internal/db/postgres/transformers/random_float_test.go
+++ b/internal/db/postgres/transformers/random_float_test.go
@@ -159,6 +159,7 @@ func TestRandomFloatTransformer_Transform(t *testing.T) {
 				driver,
 				tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/random_int_test.go b/internal/db/postgres/transformers/random_int_test.go
index e009c84e..5fe12ef3 100644
--- a/internal/db/postgres/transformers/random_int_test.go
+++ b/internal/db/postgres/transformers/random_int_test.go
@@ -131,6 +131,7 @@ func TestRandomIntTransformer_Transform_random_static(t *testing.T) {
 				driver,
 				tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
@@ -205,6 +206,7 @@ func TestRandomIntTransformer_Transform_random_dynamic(t *testing.T) {
 				driver,
 				tt.params,
 				tt.dynamicParams,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
@@ -284,6 +286,7 @@ func TestRandomIntTransformer_Transform_deterministic_dynamic(t *testing.T) {
 				driver,
 				tt.params,
 				tt.dynamicParams,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/random_ip_test.go b/internal/db/postgres/transformers/random_ip_test.go
index 4ef4c89c..033c1327 100644
--- a/internal/db/postgres/transformers/random_ip_test.go
+++ b/internal/db/postgres/transformers/random_ip_test.go
@@ -69,6 +69,7 @@ func TestRandomIpTransformer_Transform_random_dynamic(t *testing.T) {
 				driver,
 				tt.params,
 				tt.dynamicParams,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/random_mac_test.go b/internal/db/postgres/transformers/random_mac_test.go
index 30dbae0d..a624c772 100644
--- a/internal/db/postgres/transformers/random_mac_test.go
+++ b/internal/db/postgres/transformers/random_mac_test.go
@@ -131,6 +131,7 @@ func TestRandomMacTransformer_Transform_random(t *testing.T) {
 				driver,
 				tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/random_numeric_test.go b/internal/db/postgres/transformers/random_numeric_test.go
index 56d87d19..9f763bd6 100644
--- a/internal/db/postgres/transformers/random_numeric_test.go
+++ b/internal/db/postgres/transformers/random_numeric_test.go
@@ -95,6 +95,7 @@ func TestBigIntTransformer_Transform_random_static(t *testing.T) {
 				driver,
 				tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
@@ -175,6 +176,7 @@ func TestBigIntTransformer_Transform_random_dynamic(t *testing.T) {
 				driver,
 				tt.params,
 				tt.dynamicParams,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
@@ -254,6 +256,7 @@ func TestBigIntTransformer_Transform_deterministic_dynamic(t *testing.T) {
 				driver,
 				tt.params,
 				tt.dynamicParams,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/random_person_test.go b/internal/db/postgres/transformers/random_person_test.go
index ac0b69a8..8165c107 100644
--- a/internal/db/postgres/transformers/random_person_test.go
+++ b/internal/db/postgres/transformers/random_person_test.go
@@ -32,6 +32,7 @@ func TestRandomPersonTransformer_Transform_static_fullname(t *testing.T) {
 		driver,
 		params,
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	require.Empty(t, warnings)
@@ -69,6 +70,7 @@ func TestRandomPersonTransformer_Transform_static_firstname(t *testing.T) {
 		driver,
 		params,
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	require.Empty(t, warnings)
@@ -106,6 +108,7 @@ func TestRandomPersonTransformer_Transform_static_lastname(t *testing.T) {
 		driver,
 		params,
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/random_string_test.go b/internal/db/postgres/transformers/random_string_test.go
index 8db5fe04..1efd36da 100644
--- a/internal/db/postgres/transformers/random_string_test.go
+++ b/internal/db/postgres/transformers/random_string_test.go
@@ -91,6 +91,7 @@ func TestRandomStringTransformer_Transform(t *testing.T) {
 				driver,
 				tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/random_unix_timestamp_test.go b/internal/db/postgres/transformers/random_unix_timestamp_test.go
index 83821476..44da8821 100644
--- a/internal/db/postgres/transformers/random_unix_timestamp_test.go
+++ b/internal/db/postgres/transformers/random_unix_timestamp_test.go
@@ -125,6 +125,7 @@ func TestUnixTimestampTransformer_Transform__positive_cases__static(t *testing.T
 				context.Background(),
 				driver, tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
@@ -200,6 +201,7 @@ func TestUnixTimestampTransformer_Transform_null_cases(t *testing.T) {
 				context.Background(),
 				driver, tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
@@ -276,6 +278,7 @@ func TestUnixTimestampTransformer_Transform_dynamic(t *testing.T) {
 				driver,
 				tt.params,
 				tt.dynamicParams,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/random_uuid_test.go b/internal/db/postgres/transformers/random_uuid_test.go
index 3a2358a5..4bf31f66 100644
--- a/internal/db/postgres/transformers/random_uuid_test.go
+++ b/internal/db/postgres/transformers/random_uuid_test.go
@@ -76,6 +76,7 @@ func TestUuidTransformer_Transform_uuid_type(t *testing.T) {
 				driver,
 				tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/real_address_test.go b/internal/db/postgres/transformers/real_address_test.go
index 44a1dbff..d40e1372 100644
--- a/internal/db/postgres/transformers/real_address_test.go
+++ b/internal/db/postgres/transformers/real_address_test.go
@@ -44,6 +44,7 @@ func TestRealAddressTransformer_Transform(t *testing.T) {
 			"columns": rawData,
 		},
 		nil,
+		"",
 	)
 
 	require.NoError(t, err)
@@ -77,6 +78,7 @@ func TestMakeNewFakeTransformerFunction_parsing_error(t *testing.T) {
 			"columns": rawData,
 		},
 		nil,
+		"",
 	)
 	require.Len(t, warnings, 1)
 	require.Equal(t, "error parsing template", warnings[0].Msg)
@@ -102,6 +104,7 @@ func TestMakeNewFakeTransformerFunction_validation_error(t *testing.T) {
 			"columns": rawData,
 		},
 		nil,
+		"",
 	)
 	require.Len(t, warnings, 1)
 	require.Equal(t, "error validating template", warnings[0].Msg)
diff --git a/internal/db/postgres/transformers/regexp_replace_test.go b/internal/db/postgres/transformers/regexp_replace_test.go
index a26f096c..fe27e797 100644
--- a/internal/db/postgres/transformers/regexp_replace_test.go
+++ b/internal/db/postgres/transformers/regexp_replace_test.go
@@ -52,6 +52,7 @@ func TestRegexpReplaceTransformer_Transform2(t *testing.T) {
 				driver,
 				tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/replace_test.go b/internal/db/postgres/transformers/replace_test.go
index 996ec672..1d31675d 100644
--- a/internal/db/postgres/transformers/replace_test.go
+++ b/internal/db/postgres/transformers/replace_test.go
@@ -87,6 +87,7 @@ func TestReplaceTransformer_Transform(t *testing.T) {
 				driver,
 				tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
@@ -146,6 +147,7 @@ func TestReplaceTransformer_Transform_with_raw_value(t *testing.T) {
 				driver,
 				tt.params,
 				nil,
+				"",
 			)
 			require.NoError(t, err)
 			require.Empty(t, warnings)
@@ -185,6 +187,7 @@ func TestReplaceTransformer_Transform_with_validation_error(t *testing.T) {
 		driver,
 		params,
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	assert.NotEmpty(t, warnings)
diff --git a/internal/db/postgres/transformers/ro_record_context.go b/internal/db/postgres/transformers/ro_record_context.go
deleted file mode 100644
index 671adac8..00000000
--- a/internal/db/postgres/transformers/ro_record_context.go
+++ /dev/null
@@ -1,47 +0,0 @@
-package transformers
-
-import (
-	"github.com/greenmaskio/greenmask/pkg/toolkit"
-)
-
-type RoRecordContext struct {
-	rc *toolkit.RecordContext
-}
-
-func NewRoRecordContext() *RoRecordContext {
-	return &RoRecordContext{
-		rc: &toolkit.RecordContext{},
-	}
-}
-
-func (cc *RoRecordContext) clean() {
-	cc.rc.Clean()
-}
-
-func (cc *RoRecordContext) setRecord(r *toolkit.Record) {
-	cc.rc.SetRecord(r)
-}
-
-func (cc *RoRecordContext) GetColumnValue(name string) (any, error) {
-	return cc.rc.GetColumnValue(name)
-}
-
-func (cc *RoRecordContext) GetColumnRawValue(name string) (any, error) {
-	return cc.rc.GetRawColumnValue(name)
-}
-
-func (cc *RoRecordContext) EncodeValueByColumn(name string, v any) (any, error) {
-	return cc.rc.EncodeValueByColumn(name, v)
-}
-
-func (cc *RoRecordContext) DecodeValueByColumn(name string, v any) (any, error) {
-	return cc.rc.DecodeValueByColumn(name, v)
-}
-
-func (cc *RoRecordContext) EncodeValueByType(name string, v any) (any, error) {
-	return cc.rc.EncodeValueByType(name, v)
-}
-
-func (cc *RoRecordContext) DecodeValueByType(name string, v any) (any, error) {
-	return cc.rc.DecodeValueByType(name, v)
-}
diff --git a/internal/db/postgres/transformers/set_null_test.go b/internal/db/postgres/transformers/set_null_test.go
index 7f10cdaf..dae225ae 100644
--- a/internal/db/postgres/transformers/set_null_test.go
+++ b/internal/db/postgres/transformers/set_null_test.go
@@ -37,6 +37,7 @@ func TestSetNullTransformer_Transform(t *testing.T) {
 			"column": toolkit.ParamsValue(columnName),
 		},
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	assert.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/template_record_test.go b/internal/db/postgres/transformers/template_record_test.go
index 4a5424b6..e8b8866a 100644
--- a/internal/db/postgres/transformers/template_record_test.go
+++ b/internal/db/postgres/transformers/template_record_test.go
@@ -60,6 +60,7 @@ func TestTemplateRecordTransformer_Transform_date(t *testing.T) {
 			"template": toolkit.ParamsValue(template),
 		},
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	require.Empty(t, warnings)
@@ -85,7 +86,7 @@ func TestTemplateRecordTransformer_Transform_date(t *testing.T) {
 func TestTemplateRecordTransformer_Transform_json(t *testing.T) {
 	var columnName = "doc"
 	var template = `
-	  {{ $val := .GetRawColumnValue "doc" }}
+	  {{ $val := .GetColumnRawValue "doc" }}
 	  {{ jsonSet "name" "hello" $val | jsonValidate | .SetColumnValue "doc" }}
 	`
 
@@ -109,6 +110,7 @@ func TestTemplateRecordTransformer_Transform_json(t *testing.T) {
 			"template": toolkit.ParamsValue(template),
 		},
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	require.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/template_test.go b/internal/db/postgres/transformers/template_test.go
index 3da253cc..c1526288 100644
--- a/internal/db/postgres/transformers/template_test.go
+++ b/internal/db/postgres/transformers/template_test.go
@@ -48,6 +48,7 @@ func TestTemplateTransformer_Transform_int(t *testing.T) {
 			"template": toolkit.ParamsValue(template),
 		},
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	assert.Empty(t, warnings)
@@ -86,6 +87,7 @@ func TestTemplateTransformer_Transform_timestamp(t *testing.T) {
 			"template": toolkit.ParamsValue(template),
 		},
 		nil,
+		"",
 	)
 	require.NoError(t, err)
 	assert.Empty(t, warnings)
diff --git a/internal/db/postgres/transformers/utils/definition.go b/internal/db/postgres/transformers/utils/definition.go
index c09ef43b..6db05e50 100644
--- a/internal/db/postgres/transformers/utils/definition.go
+++ b/internal/db/postgres/transformers/utils/definition.go
@@ -18,6 +18,9 @@ import (
 	"context"
 	"fmt"
 
+	"github.com/expr-lang/expr"
+	"github.com/expr-lang/expr/vm"
+
 	"github.com/greenmaskio/greenmask/pkg/toolkit"
 )
 
@@ -56,10 +59,36 @@ type TransformerContext struct {
 	Transformer       Transformer
 	StaticParameters  map[string]*toolkit.StaticParameter
 	DynamicParameters map[string]*toolkit.DynamicParameter
+	whenCond          *vm.Program
+	whenEnv           expr.Option
+	rc                *toolkit.RecordContext
+}
+
+func (tc *TransformerContext) SetRecord(r *toolkit.Record) {
+	tc.rc.SetRecord(r)
+}
+
+func (tc *TransformerContext) EvaluateWhen() (bool, error) {
+	if tc.whenCond == nil {
+		return true, nil
+	}
+
+	output, err := expr.Run(tc.whenCond, nil)
+	if err != nil {
+		return false, fmt.Errorf("unable to evaluate when condition: %w", err)
+	}
+
+	cond, ok := output.(bool)
+	if ok {
+		return cond, nil
+	}
+
+	return false, fmt.Errorf("when condition should return boolean, got (%T) and value %+v", cond, cond)
 }
 
 func (d *TransformerDefinition) Instance(
 	ctx context.Context, driver *toolkit.Driver, rawParams map[string]toolkit.ParamsValue, dynamicParameters map[string]*toolkit.DynamicParamValue,
+	whenCond string,
 ) (*TransformerContext, toolkit.ValidationWarnings, error) {
 	// DecodeValue parameters and get the pgcopy of parsed
 	params, parametersWarnings, err := toolkit.InitParameters(driver, d.Parameters, rawParams, dynamicParameters)
@@ -103,9 +132,51 @@ func (d *TransformerDefinition) Instance(
 	res = append(res, schemaWarnings...)
 	res = append(res, transformerWarnings...)
 
+	cond, rc, condWarns := compileCond(whenCond, driver)
+	res = append(res, condWarns...)
+
 	return &TransformerContext{
 		Transformer:       t,
 		StaticParameters:  staticParams,
 		DynamicParameters: dynamicParams,
+		whenCond:          cond,
+		rc:                rc,
 	}, res, nil
 }
+
+func compileCond(whenCond string, driver *toolkit.Driver) (*vm.Program, *toolkit.RecordContext, toolkit.ValidationWarnings) {
+	if whenCond == "" {
+		return nil, nil, nil
+	}
+	rc, funcs := newRecordContext(driver)
+
+	cond, err := expr.Compile(whenCond, funcs...)
+	if err != nil {
+		return nil, nil, toolkit.ValidationWarnings{
+			toolkit.NewValidationWarning().
+				SetSeverity(toolkit.ErrorValidationSeverity).
+				AddMeta("Error", err.Error()).
+				SetMsg("unable to compile when condition"),
+		}
+	}
+
+	return cond, rc, nil
+}
+
+func newRecordContext(driver *toolkit.Driver) (*toolkit.RecordContext, []expr.Option) {
+	var funcs []expr.Option
+	rctx := toolkit.NewRecordContext()
+	for _, c := range driver.Table.Columns {
+
+		f := expr.Function(
+			c.Name,
+			func(name string) func(params ...any) (any, error) {
+				return func(params ...any) (any, error) {
+					return rctx.GetColumnRawValue(name)
+				}
+			}(c.Name),
+		)
+		funcs = append(funcs, f)
+	}
+	return rctx, funcs
+}
diff --git a/internal/db/postgres/transformers/utils/definition_test.go b/internal/db/postgres/transformers/utils/definition_test.go
index 02eb72e6..f23adfe5 100644
--- a/internal/db/postgres/transformers/utils/definition_test.go
+++ b/internal/db/postgres/transformers/utils/definition_test.go
@@ -100,7 +100,7 @@ func TestDefinition(t *testing.T) {
 		"replace": []byte("2023-08-27 12:08:11.304895"),
 	}
 
-	_, warnings, err := TestTransformerDefinition.Instance(context.Background(), driver, rawParams, nil)
+	_, warnings, err := TestTransformerDefinition.Instance(context.Background(), driver, rawParams, nil, "")
 	require.NoError(t, err)
 	assert.Empty(t, warnings)
 }
diff --git a/internal/domains/config.go b/internal/domains/config.go
index 84d9a5c3..7083e8b3 100644
--- a/internal/domains/config.go
+++ b/internal/domains/config.go
@@ -144,6 +144,7 @@ type TransformerConfig struct {
 	// this is used only due to https://github.com/spf13/viper/issues/373
 	MetadataParams map[string]any            `mapstructure:"-" yaml:"params,omitempty" json:"params,omitempty"`
 	DynamicParams  toolkit.DynamicParameters `mapstructure:"dynamic_params" yaml:"dynamic_params" json:"dynamic_params,omitempty"`
+	When           string                    `mapstructure:"when" yaml:"when" json:"when,omitempty"`
 }
 
 type Table struct {
@@ -154,6 +155,7 @@ type Table struct {
 	Transformers        []*TransformerConfig `mapstructure:"transformers" yaml:"transformers" json:"transformers,omitempty"`
 	ColumnsTypeOverride map[string]string    `mapstructure:"columns_type_override" yaml:"columns_type_override" json:"columns_type_override,omitempty"`
 	SubsetConds         []string             `mapstructure:"subset_conds" yaml:"subset_conds" json:"subset_conds,omitempty"`
+	When                string               `mapstructure:"when" yaml:"when" json:"when,omitempty"`
 }
 
 // DummyConfig - This is a dummy config to the viper workaround
diff --git a/pkg/toolkit/dynamic_parameter.go b/pkg/toolkit/dynamic_parameter.go
index 10535f60..99bb2aff 100644
--- a/pkg/toolkit/dynamic_parameter.go
+++ b/pkg/toolkit/dynamic_parameter.go
@@ -58,7 +58,7 @@ func (dpc *DynamicParameterContext) GetValue() (any, error) {
 }
 
 func (dpc *DynamicParameterContext) GetRawValue() (any, error) {
-	return dpc.rc.GetRawColumnValue(dpc.column.Name)
+	return dpc.rc.GetColumnRawValue(dpc.column.Name)
 }
 
 func (dpc *DynamicParameterContext) GetColumnValue(name string) (any, error) {
@@ -66,7 +66,7 @@ func (dpc *DynamicParameterContext) GetColumnValue(name string) (any, error) {
 }
 
 func (dpc *DynamicParameterContext) GetColumnRawValue(name string) (any, error) {
-	return dpc.rc.GetRawColumnValue(name)
+	return dpc.rc.GetColumnRawValue(name)
 }
 
 func (dpc *DynamicParameterContext) EncodeValue(v any) (any, error) {
diff --git a/pkg/toolkit/template_record_context.go b/pkg/toolkit/template_record_context.go
index e3a0da06..10daa7f7 100644
--- a/pkg/toolkit/template_record_context.go
+++ b/pkg/toolkit/template_record_context.go
@@ -61,7 +61,7 @@ func (rc *RecordContext) GetColumnValue(name string) (any, error) {
 	return v.Value, nil
 }
 
-func (rc *RecordContext) GetRawColumnValue(name string) (any, error) {
+func (rc *RecordContext) GetColumnRawValue(name string) (any, error) {
 	v, err := rc.record.GetRawColumnValueByName(name)
 	if err != nil {
 		return nil, err
@@ -87,7 +87,7 @@ func (rc *RecordContext) SetColumnValue(name string, v any) (bool, error) {
 	return true, nil
 }
 
-func (rc *RecordContext) SetRawColumnValue(name string, v any) (bool, error) {
+func (rc *RecordContext) SetColumnRawValue(name string, v any) (bool, error) {
 	var val *RawValue
 	switch vv := v.(type) {
 	case NullType: