diff --git a/api/crawler/types.go b/api/crawler/types.go
index df455f0a..5892daa5 100644
--- a/api/crawler/types.go
+++ b/api/crawler/types.go
@@ -1,6 +1,9 @@
 package crawler
 
 import (
+	"bytes"
+	"encoding/json"
+	"fmt"
 	"time"
 
 	"github.com/algolia/algoliasearch-client-go/v4/algolia/search"
@@ -64,13 +67,13 @@ type Config struct {
 	StartUrls   []string `json:"startUrls,omitempty"`
 	Sitemaps    []string `json:"sitemaps,omitempty"`
 
-	ExclusionPatterns []string `json:"exclusionPatterns,omitempty"`
-	IgnoreQueryParams []string `json:"ignoreQueryParams,omitempty"`
-	RenderJavaScript  bool     `json:"renderJavaScript,omitempty"`
-	RateLimit         int      `json:"rateLimit,omitempty"`
-	ExtraUrls         []string `json:"extraUrls,omitempty"`
-	MaxDepth          int      `json:"maxDepth,omitempty"`
-	MaxURLs           int      `json:"maxUrls,omitempty"`
+	ExclusionPatterns []string          `json:"exclusionPatterns,omitempty"`
+	IgnoreQueryParams []string          `json:"ignoreQueryParams,omitempty"`
+	RenderJavaScript  *RenderJavaScript `json:"renderJavaScript,omitempty"`
+	RateLimit         int               `json:"rateLimit,omitempty"`
+	ExtraUrls         []string          `json:"extraUrls,omitempty"`
+	MaxDepth          int               `json:"maxDepth,omitempty"`
+	MaxURLs           int               `json:"maxUrls,omitempty"`
 
 	IgnoreRobotsTxtRules bool `json:"ignoreRobotsTxtRules,omitempty"`
 	IgnoreNoIndex        bool `json:"ignoreNoIndex,omitempty"`
@@ -83,6 +86,60 @@ type Config struct {
 	Actions []*Action `json:"actions,omitempty"`
 }
 
+type RenderJavaScript struct {
+	Enabled bool
+
+	raw json.RawMessage
+}
+
+func (r *RenderJavaScript) UnmarshalJSON(data []byte) error {
+	trimmed := bytes.TrimSpace(data)
+	if len(trimmed) == 0 || bytes.Equal(trimmed, []byte("null")) {
+		return nil
+	}
+
+	switch trimmed[0] {
+	case 't', 'f':
+		var enabled bool
+		if err := json.Unmarshal(trimmed, &enabled); err != nil {
+			return err
+		}
+		r.Enabled = enabled
+		return nil
+	case '[':
+		var patterns []json.RawMessage
+		if err := json.Unmarshal(trimmed, &patterns); err != nil {
+			return err
+		}
+		r.Enabled = len(patterns) > 0
+	case '{':
+		var object struct {
+			Enabled *bool `json:"enabled"`
+		}
+		if err := json.Unmarshal(trimmed, &object); err != nil {
+			return err
+		}
+		r.Enabled = object.Enabled == nil || *object.Enabled
+	default:
+		return fmt.Errorf(
+			"renderJavaScript must be a boolean, an array of URL patterns or an object, got %s",
+			trimmed,
+		)
+	}
+
+	r.raw = bytes.Clone(trimmed)
+
+	return nil
+}
+
+func (r *RenderJavaScript) MarshalJSON() ([]byte, error) {
+	if len(r.raw) > 0 {
+		return bytes.Clone(r.raw), nil
+	}
+
+	return json.Marshal(r.Enabled)
+}
+
 // Action is a Crawler configuration action.
 type Action struct {
 	IndexName        string          `json:"indexName"`
diff --git a/api/crawler/types_test.go b/api/crawler/types_test.go
new file mode 100644
index 00000000..5a41cf1b
--- /dev/null
+++ b/api/crawler/types_test.go
@@ -0,0 +1,176 @@
+package crawler
+
+import (
+	"encoding/json"
+	"reflect"
+	"strings"
+	"testing"
+)
+
+func TestRenderJavaScript_UnmarshalJSON(t *testing.T) {
+	tests := []struct {
+		name    string
+		payload string
+		want    bool
+		wantErr bool
+	}{
+		{name: "bool true", payload: `true`, want: true},
+		{name: "bool false", payload: `false`, want: false},
+		{name: "null", payload: `null`, want: false},
+		{
+			name:    "array of patterns",
+			payload: `["https://example.com/docs/**","https://example.com/api/**"]`,
+			want:    true,
+		},
+		{name: "empty array", payload: `[]`, want: false},
+		{
+			name:    "object with enabled false",
+			payload: `{"enabled":false,"waitTime":{"min":1000,"max":5000}}`,
+			want:    false,
+		},
+		{
+			name:    "object with enabled true",
+			payload: `{"enabled":true,"adblock":true,"patterns":["https://example.com/**"]}`,
+			want:    true,
+		},
+		{
+			name:    "object without enabled",
+			payload: `{"waitTime":{"min":1000,"max":5000}}`,
+			want:    true,
+		},
+		{name: "number", payload: `42`, wantErr: true},
+		{name: "string", payload: `"yes"`, wantErr: true},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var got RenderJavaScript
+			err := json.Unmarshal([]byte(tt.payload), &got)
+
+			if tt.wantErr {
+				if err == nil {
+					t.Fatalf("expected an error for payload %s, got nil", tt.payload)
+				}
+				return
+			}
+			if err != nil {
+				t.Fatalf("unexpected error for payload %s: %v", tt.payload, err)
+			}
+			if got.Enabled != tt.want {
+				t.Errorf("expected Enabled %t, got %t", tt.want, got.Enabled)
+			}
+		})
+	}
+}
+
+func TestRenderJavaScript_RoundTrip(t *testing.T) {
+	tests := []struct {
+		name    string
+		payload string
+	}{
+		{name: "bool", payload: `{"renderJavaScript":true}`},
+		{
+			name:    "array",
+			payload: `{"renderJavaScript":["https://example.com/docs/**","https://example.com/api/**"]}`,
+		},
+		{
+			name:    "object",
+			payload: `{"renderJavaScript":{"enabled":true,"waitTime":{"min":1000,"max":5000},"adblock":true,"patterns":["https://example.com/**"]}}`,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var config Config
+			if err := json.Unmarshal([]byte(tt.payload), &config); err != nil {
+				t.Fatalf("unmarshal: %v", err)
+			}
+
+			got, err := json.Marshal(&config)
+			if err != nil {
+				t.Fatalf("marshal: %v", err)
+			}
+
+			var want, have interface{}
+			if err := json.Unmarshal([]byte(tt.payload), &want); err != nil {
+				t.Fatalf("unmarshal expected payload: %v", err)
+			}
+			if err := json.Unmarshal(got, &have); err != nil {
+				t.Fatalf("unmarshal marshalled payload: %v", err)
+			}
+			if !reflect.DeepEqual(want, have) {
+				t.Errorf("expected %s, got %s", tt.payload, got)
+			}
+		})
+	}
+}
+
+func TestCrawler_UnmarshalJSON_RenderJavaScriptPatterns(t *testing.T) {
+	payload := `{
+		"id": "1a2b3c4d-1234-5678-90ab-cdef12345678",
+		"name": "my-crawler",
+		"running": true,
+		"createdAt": "2024-01-02T03:04:05.000Z",
+		"config": {
+			"appId": "APP_ID",
+			"indexPrefix": "crawler_",
+			"startUrls": ["https://example.com"],
+			"renderJavaScript": ["https://example.com/docs/**"],
+			"rateLimit": 8,
+			"actions": [
+				{
+					"indexName": "docs",
+					"pathsToMatch": ["https://example.com/docs/**"],
+					"recordExtractor": {"__type": "function", "source": "() => {}"}
+				}
+			]
+		}
+	}`
+
+	var crawler Crawler
+	if err := json.Unmarshal([]byte(payload), &crawler); err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if crawler.Config == nil {
+		t.Fatal("expected a config, got nil")
+	}
+	if crawler.Config.RenderJavaScript == nil {
+		t.Fatal("expected a renderJavaScript value, got nil")
+	}
+	if !crawler.Config.RenderJavaScript.Enabled {
+		t.Error("expected Enabled true, got false")
+	}
+}
+
+func TestConfig_MarshalJSON_WithoutRenderJavaScript(t *testing.T) {
+	got, err := json.Marshal(&Config{AppID: "APP_ID"})
+	if err != nil {
+		t.Fatalf("marshal: %v", err)
+	}
+	if strings.Contains(string(got), "renderJavaScript") {
+		t.Errorf("expected no renderJavaScript key, got %s", got)
+	}
+}
+
+func TestRenderJavaScript_MarshalJSON_FromGo(t *testing.T) {
+	tests := []struct {
+		name  string
+		value *RenderJavaScript
+		want  string
+	}{
+		{name: "enabled", value: &RenderJavaScript{Enabled: true}, want: `true`},
+		{name: "disabled", value: &RenderJavaScript{}, want: `false`},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := json.Marshal(tt.value)
+			if err != nil {
+				t.Fatalf("marshal: %v", err)
+			}
+			if string(got) != tt.want {
+				t.Errorf("expected %s, got %s", tt.want, got)
+			}
+		})
+	}
+}