diff --git a/packages/seroval/src/core/base/async.ts b/packages/seroval/src/core/base/async.ts
index 7235e5bd..ac10054d 100644
--- a/packages/seroval/src/core/base/async.ts
+++ b/packages/seroval/src/core/base/async.ts
@@ -60,8 +60,6 @@ import type {
   SerovalResponseNode,
   SerovalSetNode,
   SerovalDataViewNode,
-  SerovalIndexedValueNode,
-  SerovalReferenceNode,
 } from '../types';
 import { createURLNode, createURLSearchParamsNode, createDOMExceptionNode } from '../web-api';
 
@@ -71,14 +69,6 @@ type ObjectLikeNode =
   | SerovalPromiseNode;
 
 export default abstract class BaseAsyncParserContext extends BaseParserContext {
-  protected abstract getReference<T>(
-    current: T,
-  ): number | SerovalIndexedValueNode | SerovalReferenceNode;
-
-  protected abstract getStrictReference<T>(
-    current: T,
-  ): SerovalIndexedValueNode | SerovalReferenceNode;
-
   private async parseItems(
     current: unknown[],
   ): Promise<SerovalNode[]> {
diff --git a/packages/seroval/src/core/base/sync.ts b/packages/seroval/src/core/base/sync.ts
index fa3db5ba..7435f12c 100644
--- a/packages/seroval/src/core/base/sync.ts
+++ b/packages/seroval/src/core/base/sync.ts
@@ -51,8 +51,6 @@ import type {
   SerovalTypedArrayNode,
   SerovalBigIntTypedArrayNode,
   SerovalDataViewNode,
-  SerovalIndexedValueNode,
-  SerovalReferenceNode,
 } from '../types';
 import { createDOMExceptionNode, createURLNode, createURLSearchParamsNode } from '../web-api';
 
@@ -65,14 +63,6 @@ export interface BaseSyncParserContextOptions extends BaseParserContextOptions {
 }
 
 export default abstract class BaseSyncParserContext extends BaseParserContext {
-  protected abstract getReference<T>(
-    current: T,
-  ): number | SerovalIndexedValueNode | SerovalReferenceNode;
-
-  protected abstract getStrictReference<T>(
-    current: T,
-  ): SerovalIndexedValueNode | SerovalReferenceNode;
-
   protected parseItems(
     current: unknown[],
   ): SerovalNode[] {
diff --git a/packages/seroval/src/core/cross/async.ts b/packages/seroval/src/core/cross/async.ts
index feb22f5f..89c9c88a 100644
--- a/packages/seroval/src/core/cross/async.ts
+++ b/packages/seroval/src/core/cross/async.ts
@@ -1,26 +1,9 @@
 import BaseAsyncParserContext from '../base/async';
-import type { SerovalIndexedValueNode, SerovalReferenceNode } from '../types';
 import type { CrossParserContextOptions } from './cross-parser';
-import { getCrossReference, getStrictCrossReference } from './cross-parser';
 import type { SerovalMode } from '../plugin';
 
 export type CrossAsyncParserContextOptions = CrossParserContextOptions
 
 export default class CrossAsyncParserContext extends BaseAsyncParserContext {
   readonly mode: SerovalMode = 'cross';
-
-  refs: Map<unknown, number>;
-
-  constructor(options: CrossAsyncParserContextOptions) {
-    super(options);
-    this.refs = options.refs || new Map<unknown, number>();
-  }
-
-  protected getReference<T>(current: T): number | SerovalIndexedValueNode | SerovalReferenceNode {
-    return getCrossReference(this.refs, current);
-  }
-
-  protected getStrictReference<T>(current: T): SerovalIndexedValueNode | SerovalReferenceNode {
-    return getStrictCrossReference(this.refs, current);
-  }
 }
diff --git a/packages/seroval/src/core/cross/cross-parser.ts b/packages/seroval/src/core/cross/cross-parser.ts
index 64a857ac..99932aa7 100644
--- a/packages/seroval/src/core/cross/cross-parser.ts
+++ b/packages/seroval/src/core/cross/cross-parser.ts
@@ -1,7 +1,4 @@
-import { createIndexedValueNode, createReferenceNode } from '../base-primitives';
 import type { BaseParserContextOptions } from '../parser-context';
-import { hasReferenceID } from '../reference';
-import type { SerovalIndexedValueNode, SerovalReferenceNode } from '../types';
 
 export interface CrossParserContextOptions extends BaseParserContextOptions {
   refs?: Map<unknown, number>;
@@ -10,32 +7,3 @@ export interface CrossParserContextOptions extends BaseParserContextOptions {
 export interface CrossContextOptions {
   scopeId?: string;
 }
-
-export function getCrossReference<T>(
-  refs: Map<unknown, number>,
-  value: T,
-): number | SerovalIndexedValueNode | SerovalReferenceNode {
-  const registeredID = refs.get(value);
-  if (registeredID != null) {
-    return createIndexedValueNode(registeredID);
-  }
-  const id = refs.size;
-  refs.set(value, id);
-  if (hasReferenceID(value)) {
-    return createReferenceNode(id, value);
-  }
-  return id;
-}
-
-export function getStrictCrossReference<T>(
-  refs: Map<unknown, number>,
-  value: T,
-): SerovalIndexedValueNode | SerovalReferenceNode {
-  const id = refs.get(value);
-  if (id != null) {
-    return createIndexedValueNode(id);
-  }
-  const newID = refs.size;
-  refs.set(value, newID);
-  return createReferenceNode(newID, value);
-}
diff --git a/packages/seroval/src/core/cross/index.ts b/packages/seroval/src/core/cross/index.ts
index d18b1109..9c20f5c6 100644
--- a/packages/seroval/src/core/cross/index.ts
+++ b/packages/seroval/src/core/cross/index.ts
@@ -15,12 +15,17 @@ export function crossSerialize<T>(
   source: T,
   options: CrossSerializeOptions = {},
 ): string {
-  const ctx = new SyncCrossParserContext(options);
+  const ctx = new SyncCrossParserContext({
+    plugins: options.plugins,
+    disabledFeatures: options.disabledFeatures,
+    refs: options.refs,
+  });
   const tree = ctx.parse(source);
   const serial = new CrossSerializerContext({
     plugins: options.plugins,
     features: ctx.features,
     scopeId: options.scopeId,
+    markedRefs: ctx.marked,
   });
   return serial.serializeTop(tree);
 }
@@ -33,12 +38,17 @@ export async function crossSerializeAsync<T>(
   source: T,
   options: CrossSerializeAsyncOptions = {},
 ): Promise<string> {
-  const ctx = new AsyncCrossParserContext(options);
+  const ctx = new AsyncCrossParserContext({
+    plugins: options.plugins,
+    disabledFeatures: options.disabledFeatures,
+    refs: options.refs,
+  });
   const tree = await ctx.parse(source);
   const serial = new CrossSerializerContext({
     plugins: options.plugins,
     features: ctx.features,
     scopeId: options.scopeId,
+    markedRefs: ctx.marked,
   });
   return serial.serializeTop(tree);
 }
@@ -106,6 +116,7 @@ export function crossSerializeStream<T>(
         plugins: options.plugins,
         features: ctx.features,
         scopeId: options.scopeId,
+        markedRefs: ctx.marked,
       });
 
       options.onSerialize(
diff --git a/packages/seroval/src/core/cross/serialize.ts b/packages/seroval/src/core/cross/serialize.ts
index a1e07a4a..d3afca0c 100644
--- a/packages/seroval/src/core/cross/serialize.ts
+++ b/packages/seroval/src/core/cross/serialize.ts
@@ -38,10 +38,6 @@ export default class CrossSerializerContext extends BaseSerializerContext {
     this.scopeId = options.scopeId;
   }
 
-  markRef(): void {
-    // no-op
-  }
-
   getRefParam(id: number): string {
     return GLOBAL_CONTEXT_REFERENCES + '[' + id + ']';
   }
diff --git a/packages/seroval/src/core/cross/stream.ts b/packages/seroval/src/core/cross/stream.ts
index efb40792..018f4d59 100644
--- a/packages/seroval/src/core/cross/stream.ts
+++ b/packages/seroval/src/core/cross/stream.ts
@@ -1,29 +1,9 @@
-import type {
-  SerovalIndexedValueNode,
-  SerovalReferenceNode,
-} from '../types';
 import type { BaseStreamParserContextOptions } from '../base/stream';
 import BaseStreamParserContext from '../base/stream';
 import type { SerovalMode } from '../plugin';
-import { getCrossReference, getStrictCrossReference } from './cross-parser';
 
 export type CrossStreamParserContextOptions = BaseStreamParserContextOptions
 
 export default class CrossStreamParserContext extends BaseStreamParserContext {
   readonly mode: SerovalMode = 'cross';
-
-  refs: Map<unknown, number>;
-
-  constructor(options: CrossStreamParserContextOptions) {
-    super(options);
-    this.refs = options.refs || new Map<unknown, number>();
-  }
-
-  protected getReference<T>(current: T): number | SerovalIndexedValueNode | SerovalReferenceNode {
-    return getCrossReference(this.refs, current);
-  }
-
-  protected getStrictReference<T>(current: T): SerovalIndexedValueNode | SerovalReferenceNode {
-    return getStrictCrossReference(this.refs, current);
-  }
 }
diff --git a/packages/seroval/src/core/cross/sync.ts b/packages/seroval/src/core/cross/sync.ts
index e47ffb46..4698c90d 100644
--- a/packages/seroval/src/core/cross/sync.ts
+++ b/packages/seroval/src/core/cross/sync.ts
@@ -1,25 +1,9 @@
 import BaseSyncParserContext from '../base/sync';
 import type { SerovalMode } from '../plugin';
-import type { SerovalIndexedValueNode, SerovalReferenceNode } from '../types';
-import { getStrictCrossReference, type CrossParserContextOptions, getCrossReference } from './cross-parser';
+import type { CrossParserContextOptions } from './cross-parser';
 
 export type CrossSyncParserContextOptions = CrossParserContextOptions
 
 export default class CrossSyncParserContext extends BaseSyncParserContext {
   readonly mode: SerovalMode = 'cross';
-
-  refs: Map<unknown, number>;
-
-  constructor(options: CrossSyncParserContextOptions) {
-    super(options);
-    this.refs = options.refs || new Map<unknown, number>();
-  }
-
-  protected getReference<T>(current: T): number | SerovalIndexedValueNode | SerovalReferenceNode {
-    return getCrossReference(this.refs, current);
-  }
-
-  protected getStrictReference<T>(current: T): SerovalIndexedValueNode | SerovalReferenceNode {
-    return getStrictCrossReference(this.refs, current);
-  }
 }
diff --git a/packages/seroval/src/core/parser-context.ts b/packages/seroval/src/core/parser-context.ts
index 565fe266..5ee144c1 100644
--- a/packages/seroval/src/core/parser-context.ts
+++ b/packages/seroval/src/core/parser-context.ts
@@ -1,15 +1,14 @@
+import { createIndexedValueNode, createReferenceNode } from './base-primitives';
 import { ALL_ENABLED, BIGINT_FLAG, Feature } from './compat';
 import { ERROR_CONSTRUCTOR_STRING } from './constants';
 import type { Plugin, PluginAccessOptions, SerovalMode } from './plugin';
+import { hasReferenceID } from './reference';
 import { getErrorConstructor } from './shared';
-
-export interface ParserReference {
-  ids: Map<unknown, number>;
-  marked: Set<number>;
-}
+import type { SerovalIndexedValueNode, SerovalReferenceNode } from './types';
 
 export interface BaseParserContextOptions extends PluginAccessOptions {
   disabledFeatures?: number;
+  refs?: Map<unknown, number>;
 }
 
 export abstract class BaseParserContext implements PluginAccessOptions {
@@ -17,11 +16,49 @@ export abstract class BaseParserContext implements PluginAccessOptions {
 
   features: number;
 
+  marked = new Set<number>();
+
+  refs: Map<unknown, number>;
+
   plugins?: Plugin<any, any>[] | undefined;
 
   constructor(options: BaseParserContextOptions) {
     this.plugins = options.plugins;
     this.features = ALL_ENABLED ^ (options.disabledFeatures || 0);
+    this.refs = options.refs || new Map<unknown, number>();
+  }
+
+  protected markRef(id: number): void {
+    this.marked.add(id);
+  }
+
+  protected isMarked(id: number): boolean {
+    return this.marked.has(id);
+  }
+
+  protected getReference<T>(current: T): number | SerovalIndexedValueNode | SerovalReferenceNode {
+    const registeredID = this.refs.get(current);
+    if (registeredID != null) {
+      this.markRef(registeredID);
+      return createIndexedValueNode(registeredID);
+    }
+    const id = this.refs.size;
+    this.refs.set(current, id);
+    if (hasReferenceID(current)) {
+      return createReferenceNode(id, current);
+    }
+    return id;
+  }
+
+  protected getStrictReference<T>(current: T): SerovalIndexedValueNode | SerovalReferenceNode {
+    const registeredID = this.refs.get(current);
+    if (registeredID != null) {
+      this.markRef(registeredID);
+      return createIndexedValueNode(registeredID);
+    }
+    const id = this.refs.size;
+    this.refs.set(current, id);
+    return createReferenceNode(id, current);
   }
 
   /**
diff --git a/packages/seroval/src/core/serializer-context.ts b/packages/seroval/src/core/serializer-context.ts
index c93353f7..f26f2558 100644
--- a/packages/seroval/src/core/serializer-context.ts
+++ b/packages/seroval/src/core/serializer-context.ts
@@ -66,6 +66,7 @@ const PROMISE_REJECT = 'Promise.reject';
 
 export interface BaseSerializerContextOptions extends PluginAccessOptions {
   features: number;
+  markedRefs: number[] | Set<number>;
 }
 
 export default abstract class BaseSerializerContext implements PluginAccessOptions {
@@ -94,9 +95,16 @@ export default abstract class BaseSerializerContext implements PluginAccessOptio
 
   plugins?: Plugin<any, any>[] | undefined;
 
+  /**
+   * Refs that are...referenced
+   * @private
+   */
+  marked: Set<number>;
+
   constructor(options: BaseSerializerContextOptions) {
     this.plugins = options.plugins;
     this.features = options.features;
+    this.marked = new Set(options.markedRefs);
   }
 
   abstract readonly mode: SerovalMode;
@@ -107,7 +115,13 @@ export default abstract class BaseSerializerContext implements PluginAccessOptio
    * deciding whether or not we should generate
    * an identifier for the object
    */
-  abstract markRef(id: number): void;
+  protected markRef(id: number): void {
+    this.marked.add(id);
+  }
+
+  protected isMarked(id: number): boolean {
+    return this.marked.has(id);
+  }
 
   /**
    * Converts the ID of a reference into a identifier string
@@ -197,6 +211,29 @@ export default abstract class BaseSerializerContext implements PluginAccessOptio
     this.createAssignment(this.getRefParam(ref) + '.' + key, value);
   }
 
+  /**
+   * Seroval dedupes references by keeping only one of the reference,
+   * and the rest reusing the id of the original.
+   *
+   * Normally, since serialization is depth-first process,
+   * it should always be able to serialize the original before
+   * the other references.
+   *
+   * However, Seroval also has another mechanism called "assignments" which
+   * defers serialization when a reference is made inside a temporal
+   * dead zone or when a recursion is detected. Most of the time, assignments
+   * will only use the reference not the original, the only exception
+   * here is Map which has a key-value pair, so there's a case where
+   * only one of the two has the original, the other being a reference
+   * that can cause an assignment to occur.
+   *
+   * `defer` will help us here by serializing the item without assigning
+   * it the position it's supposed to be assigned. The next reference
+   * will be replaced with the original.
+   *
+   * Take note that this only matters if the object in question has more than
+   * one deduped reference in the entire tree.
+   */
   deferred = new Map<number, string>();
 
   defer(id: number, value: string): void {
@@ -526,7 +563,7 @@ export default abstract class BaseSerializerContext implements PluginAccessOptio
       // assignment
       const parent = this.stack;
       this.stack = [];
-      if (val.t !== SerovalNodeType.IndexedValue && val.i != null) {
+      if (val.t !== SerovalNodeType.IndexedValue && val.i != null && this.isMarked(val.i)) {
         this.defer(val.i, this.serialize(val));
         this.createSetAssignment(id, keyRef, this.getRefParam(val.i));
       } else {
@@ -542,7 +579,7 @@ export default abstract class BaseSerializerContext implements PluginAccessOptio
       // Reset stack for the key serialization
       const parent = this.stack;
       this.stack = [];
-      if (val.t !== SerovalNodeType.IndexedValue && val.i != null) {
+      if (val.t !== SerovalNodeType.IndexedValue && val.i != null && this.isMarked(val.i)) {
         this.defer(val.i, this.serialize(val));
         this.createSetAssignment(id, this.getRefParam(val.i), valueRef);
       } else {
diff --git a/packages/seroval/src/core/tree/async.ts b/packages/seroval/src/core/tree/async.ts
index 75c95294..52ce872f 100644
--- a/packages/seroval/src/core/tree/async.ts
+++ b/packages/seroval/src/core/tree/async.ts
@@ -1,29 +1,9 @@
 import BaseAsyncParserContext from '../base/async';
 import type { BaseParserContextOptions } from '../parser-context';
-import type { SerovalIndexedValueNode, SerovalReferenceNode } from '../types';
 import type { SerovalMode } from '../plugin';
-import { getStrictVanillaReference, getVanillaReference } from './parser';
 
-export type AsyncParserContextOptions = BaseParserContextOptions
+export type AsyncParserContextOptions = Omit<BaseParserContextOptions, 'refs'>
 
 export default class AsyncParserContext extends BaseAsyncParserContext {
   readonly mode: SerovalMode = 'vanilla';
-
-  /**
-   * @private
-   */
-  ids: Map<unknown, number> = new Map();
-
-  /**
-   * @private
-   */
-  marked: Set<number> = new Set();
-
-  protected getReference<T>(current: T): number | SerovalIndexedValueNode | SerovalReferenceNode {
-    return getVanillaReference(this.ids, this.marked, current);
-  }
-
-  protected getStrictReference<T>(current: T): SerovalIndexedValueNode | SerovalReferenceNode {
-    return getStrictVanillaReference(this.ids, this.marked, current);
-  }
 }
diff --git a/packages/seroval/src/core/tree/index.ts b/packages/seroval/src/core/tree/index.ts
index 9b332a38..22ba6e7e 100644
--- a/packages/seroval/src/core/tree/index.ts
+++ b/packages/seroval/src/core/tree/index.ts
@@ -11,7 +11,10 @@ export function serialize<T>(
   source: T,
   options: SyncParserContextOptions = {},
 ): string {
-  const ctx = new SyncParserContext(options);
+  const ctx = new SyncParserContext({
+    plugins: options.plugins,
+    disabledFeatures: options.disabledFeatures,
+  });
   const tree = ctx.parse(source);
   const serial = new VanillaSerializerContext({
     plugins: options.plugins,
@@ -25,7 +28,10 @@ export async function serializeAsync<T>(
   source: T,
   options: AsyncParserContextOptions = {},
 ): Promise<string> {
-  const ctx = new AsyncParserContext(options);
+  const ctx = new AsyncParserContext({
+    plugins: options.plugins,
+    disabledFeatures: options.disabledFeatures,
+  });
   const tree = await ctx.parse(source);
   const serial = new VanillaSerializerContext({
     plugins: options.plugins,
@@ -50,7 +56,10 @@ export function toJSON<T>(
   source: T,
   options: SyncParserContextOptions = {},
 ): SerovalJSON {
-  const ctx = new SyncParserContext(options);
+  const ctx = new SyncParserContext({
+    plugins: options.plugins,
+    disabledFeatures: options.disabledFeatures,
+  });
   return {
     t: ctx.parse(source),
     f: ctx.features,
@@ -62,7 +71,10 @@ export async function toJSONAsync<T>(
   source: T,
   options: AsyncParserContextOptions = {},
 ): Promise<SerovalJSON> {
-  const ctx = new AsyncParserContext(options);
+  const ctx = new AsyncParserContext({
+    plugins: options.plugins,
+    disabledFeatures: options.disabledFeatures,
+  });
   return {
     t: await ctx.parse(source),
     f: ctx.features,
diff --git a/packages/seroval/src/core/tree/serialize.ts b/packages/seroval/src/core/tree/serialize.ts
index 4fa6671f..bf5d7b89 100644
--- a/packages/seroval/src/core/tree/serialize.ts
+++ b/packages/seroval/src/core/tree/serialize.ts
@@ -15,9 +15,7 @@ import type { SerovalMode } from '../plugin';
 import { Feature } from '../compat';
 import { SerovalNodeType } from '../constants';
 
-export interface VanillaSerializerContextOptions extends BaseSerializerContextOptions {
-  markedRefs: number[] | Set<number>;
-}
+export type VanillaSerializerContextOptions = BaseSerializerContextOptions
 
 export default class VanillaSerializerContext extends BaseSerializerContext {
   readonly mode: SerovalMode = 'cross';
@@ -34,23 +32,12 @@ export default class VanillaSerializerContext extends BaseSerializerContext {
    */
   valid: (number | undefined)[] = [];
 
-  /**
-   * Refs that are...referenced
-   * @private
-   */
-  marked: Set<number>;
-
   /**
    * Variables
    * @private
    */
   vars: (string | undefined)[] = [];
 
-  constructor(options: VanillaSerializerContextOptions) {
-    super(options);
-    this.marked = new Set(options.markedRefs);
-  }
-
   /**
    * Increments the number of references the referenced value has
    */
@@ -88,7 +75,7 @@ export default class VanillaSerializerContext extends BaseSerializerContext {
     index: number,
     value: string,
   ): string {
-    if (this.marked.has(index)) {
+    if (this.isMarked(index)) {
       return this.getRefParam(index) + '=' + value;
     }
     return value;
diff --git a/packages/seroval/src/core/tree/sync.ts b/packages/seroval/src/core/tree/sync.ts
index adb4947a..8e730bfd 100644
--- a/packages/seroval/src/core/tree/sync.ts
+++ b/packages/seroval/src/core/tree/sync.ts
@@ -1,29 +1,9 @@
 import BaseSyncParserContext from '../base/sync';
 import type { BaseParserContextOptions } from '../parser-context';
 import type { SerovalMode } from '../plugin';
-import type { SerovalIndexedValueNode, SerovalReferenceNode } from '../types';
-import { getStrictVanillaReference, getVanillaReference } from './parser';
 
-export type SyncParserContextOptions = BaseParserContextOptions
+export type SyncParserContextOptions = Omit<BaseParserContextOptions, 'refs'>;
 
 export default class SyncParserContext extends BaseSyncParserContext {
   readonly mode: SerovalMode = 'vanilla';
-
-  /**
-   * @private
-   */
-  ids: Map<unknown, number> = new Map();
-
-  /**
-   * @private
-   */
-  marked: Set<number> = new Set();
-
-  protected getReference<T>(current: T): number | SerovalIndexedValueNode | SerovalReferenceNode {
-    return getVanillaReference(this.ids, this.marked, current);
-  }
-
-  protected getStrictReference<T>(current: T): SerovalIndexedValueNode | SerovalReferenceNode {
-    return getStrictVanillaReference(this.ids, this.marked, current);
-  }
 }