diff --git a/.changeset/moody-dots-taste.md b/.changeset/moody-dots-taste.md
new file mode 100644
index 00000000..cde045ca
--- /dev/null
+++ b/.changeset/moody-dots-taste.md
@@ -0,0 +1,5 @@
+---
+"@xmtp/mls-client": patch
+---
+
+Add streaming callbacks
diff --git a/packages/mls-client/package.json b/packages/mls-client/package.json
index c3c178fe..9e8a3880 100644
--- a/packages/mls-client/package.json
+++ b/packages/mls-client/package.json
@@ -52,9 +52,9 @@
     "typecheck": "tsc"
   },
   "dependencies": {
+    "@xmtp/content-type-primitives": "^1.0.1",
     "@xmtp/mls-client-bindings-node": "^0.0.4",
-    "@xmtp/proto": "^3.61.1",
-    "@xmtp/xmtp-js": "^11.6.2"
+    "@xmtp/proto": "^3.61.1"
   },
   "devDependencies": {
     "@ianvs/prettier-plugin-sort-imports": "^4.2.1",
@@ -64,6 +64,7 @@
     "@typescript-eslint/eslint-plugin": "^7.8.0",
     "@typescript-eslint/parser": "^7.8.0",
     "@vitest/coverage-v8": "^1.6.0",
+    "@xmtp/xmtp-js": "workspace:^",
     "eslint": "^8.57.0",
     "eslint-config-prettier": "^9.1.0",
     "eslint-config-standard": "^17.1.0",
diff --git a/packages/mls-client/src/AsyncStream.ts b/packages/mls-client/src/AsyncStream.ts
index 490cf135..8f36428d 100644
--- a/packages/mls-client/src/AsyncStream.ts
+++ b/packages/mls-client/src/AsyncStream.ts
@@ -1,32 +1,30 @@
-type Value<T, V> = V extends undefined ? T : V
-
-type ResolveValue<T, V> = {
-  value: Value<T, V> | undefined
+type ResolveValue<T> = {
+  value: T | undefined
   done: boolean
 }
 
-type ResolveNext<T, V> = (resolveValue: ResolveValue<T, V>) => void
+type ResolveNext<T> = (resolveValue: ResolveValue<T>) => void
 
-type TransformValue<T, V> = (value: T) => Value<T, V>
+export type StreamCallback<T> = (err: Error | null, value: T) => void
 
-export class AsyncStream<T, V = undefined> {
+export class AsyncStream<T> {
   #done = false
-  #resolveNext: ResolveNext<T, V> | null
-  #queue: Value<T, V>[]
-  #transformValue?: TransformValue<T, V>
+  #resolveNext: ResolveNext<T> | null
+  #queue: T[]
 
   stopCallback: (() => void) | undefined = undefined
 
-  constructor(
-    transformValue: V extends undefined ? undefined : TransformValue<T, V>
-  ) {
+  constructor() {
     this.#queue = []
     this.#resolveNext = null
     this.#done = false
-    this.#transformValue = transformValue
   }
 
-  callback = (err: Error | null, value: T) => {
+  get isDone() {
+    return this.#done
+  }
+
+  callback: StreamCallback<T> = (err, value) => {
     if (err) {
       console.error('stream error', err)
       this.stop()
@@ -37,17 +35,11 @@ export class AsyncStream<T, V = undefined> {
       return
     }
 
-    const newValue = this.#transformValue
-      ? this.#transformValue(value)
-      : // must assert type because TypeScript can't infer that T is assignable
-        // to Value<T, V> when this.#transformValue is undefined
-        (value as unknown as Value<T, V>)
-
     if (this.#resolveNext) {
-      this.#resolveNext({ value: newValue, done: false })
+      this.#resolveNext({ value, done: false })
       this.#resolveNext = null
     } else {
-      this.#queue.push(newValue)
+      this.#queue.push(value)
     }
   }
 
@@ -59,7 +51,7 @@ export class AsyncStream<T, V = undefined> {
     this.stopCallback?.()
   }
 
-  next = (): Promise<ResolveValue<T, V>> => {
+  next = (): Promise<ResolveValue<T>> => {
     if (this.#queue.length > 0) {
       return Promise.resolve({ value: this.#queue.shift(), done: false })
     } else if (this.#done) {
diff --git a/packages/mls-client/src/Conversation.ts b/packages/mls-client/src/Conversation.ts
index 3853b730..8367093d 100644
--- a/packages/mls-client/src/Conversation.ts
+++ b/packages/mls-client/src/Conversation.ts
@@ -1,10 +1,9 @@
 import type {
   NapiGroup,
   NapiListMessagesOptions,
-  NapiMessage,
 } from '@xmtp/mls-client-bindings-node'
 import type { ContentTypeId } from '@xmtp/xmtp-js'
-import { AsyncStream } from '@/AsyncStream'
+import { AsyncStream, type StreamCallback } from '@/AsyncStream'
 import type { Client } from '@/Client'
 import { DecodedMessage } from '@/DecodedMessage'
 import { nsToDate } from '@/helpers/date'
@@ -78,12 +77,17 @@ export class Conversation {
     return this.#group.sync()
   }
 
-  stream() {
-    const asyncStream = new AsyncStream<NapiMessage, DecodedMessage>(
-      (message) => new DecodedMessage(this.#client, message)
-    )
-    const stream = this.#group.stream(asyncStream.callback)
+  stream(callback?: StreamCallback<DecodedMessage>) {
+    const asyncStream = new AsyncStream<DecodedMessage>()
+
+    const stream = this.#group.stream((err, message) => {
+      const decodedMessage = new DecodedMessage(this.#client, message)
+      asyncStream.callback(err, decodedMessage)
+      callback?.(err, decodedMessage)
+    })
+
     asyncStream.stopCallback = stream.end.bind(stream)
+
     return asyncStream
   }
 
diff --git a/packages/mls-client/src/Conversations.ts b/packages/mls-client/src/Conversations.ts
index d01d143c..6501a847 100644
--- a/packages/mls-client/src/Conversations.ts
+++ b/packages/mls-client/src/Conversations.ts
@@ -1,11 +1,9 @@
 import type {
   GroupPermissions,
   NapiConversations,
-  NapiGroup,
   NapiListMessagesOptions,
-  NapiMessage,
 } from '@xmtp/mls-client-bindings-node'
-import { AsyncStream } from '@/AsyncStream'
+import { AsyncStream, type StreamCallback } from '@/AsyncStream'
 import type { Client } from '@/Client'
 import { Conversation } from '@/Conversation'
 import { DecodedMessage } from '@/DecodedMessage'
@@ -13,10 +11,16 @@ import { DecodedMessage } from '@/DecodedMessage'
 export class Conversations {
   #client: Client
   #conversations: NapiConversations
+  #map: Map<string, Conversation>
 
   constructor(client: Client, conversations: NapiConversations) {
     this.#client = client
     this.#conversations = conversations
+    this.#map = new Map()
+  }
+
+  get(id: string) {
+    return this.#map.get(id)
   }
 
   async newConversation(
@@ -27,35 +31,53 @@ export class Conversations {
       accountAddresses,
       permissions
     )
-    return new Conversation(this.#client, group)
+    const conversation = new Conversation(this.#client, group)
+    this.#map.set(conversation.id, conversation)
+    return conversation
   }
 
   async list(options?: NapiListMessagesOptions) {
     const groups = await this.#conversations.list(options)
-    return groups.map((group) => new Conversation(this.#client, group))
+    return groups.map((group) => {
+      const conversation = new Conversation(this.#client, group)
+      this.#map.set(conversation.id, conversation)
+      return conversation
+    })
   }
 
   async sync() {
     return this.#conversations.sync()
   }
 
-  stream() {
-    const asyncStream = new AsyncStream<NapiGroup, Conversation>(
-      (group) => new Conversation(this.#client, group)
-    )
-    const stream = this.#conversations.stream(asyncStream.callback)
+  stream(callback?: StreamCallback<Conversation>) {
+    const asyncStream = new AsyncStream<Conversation>()
+
+    const stream = this.#conversations.stream((err, group) => {
+      const conversation = new Conversation(this.#client, group)
+      this.#map.set(conversation.id, conversation)
+      asyncStream.callback(err, conversation)
+      callback?.(err, conversation)
+    })
+
     asyncStream.stopCallback = stream.end.bind(stream)
+
     return asyncStream
   }
 
-  async streamAllMessages() {
+  async streamAllMessages(callback?: StreamCallback<DecodedMessage>) {
     // sync conversations first
     await this.sync()
-    const asyncStream = new AsyncStream<NapiMessage, DecodedMessage>(
-      (message) => new DecodedMessage(this.#client, message)
-    )
-    const stream = this.#conversations.streamAllMessages(asyncStream.callback)
+
+    const asyncStream = new AsyncStream<DecodedMessage>()
+
+    const stream = this.#conversations.streamAllMessages((err, message) => {
+      const decodedMessage = new DecodedMessage(this.#client, message)
+      asyncStream.callback(err, decodedMessage)
+      callback?.(err, decodedMessage)
+    })
+
     asyncStream.stopCallback = stream.end.bind(stream)
+
     return asyncStream
   }
 }
diff --git a/packages/mls-client/src/codecs/GroupUpdatedCodec.ts b/packages/mls-client/src/codecs/GroupUpdatedCodec.ts
index fe540fb2..402318ed 100644
--- a/packages/mls-client/src/codecs/GroupUpdatedCodec.ts
+++ b/packages/mls-client/src/codecs/GroupUpdatedCodec.ts
@@ -1,9 +1,9 @@
-import { mlsTranscriptMessages } from '@xmtp/proto'
 import {
   ContentTypeId,
   type ContentCodec,
   type EncodedContent,
-} from '@xmtp/xmtp-js'
+} from '@xmtp/content-type-primitives'
+import { mlsTranscriptMessages } from '@xmtp/proto'
 
 export const ContentTypeGroupUpdated = new ContentTypeId({
   authorityId: 'xmtp.org',
diff --git a/packages/mls-client/src/index.ts b/packages/mls-client/src/index.ts
index f373bcd0..b538d9af 100644
--- a/packages/mls-client/src/index.ts
+++ b/packages/mls-client/src/index.ts
@@ -13,3 +13,4 @@ export {
   ContentTypeGroupUpdated,
   GroupUpdatedCodec,
 } from './codecs/GroupUpdatedCodec'
+export type { StreamCallback } from './AsyncStream'
diff --git a/packages/mls-client/test/Conversations.test.ts b/packages/mls-client/test/Conversations.test.ts
index 30721ab6..d569300d 100644
--- a/packages/mls-client/test/Conversations.test.ts
+++ b/packages/mls-client/test/Conversations.test.ts
@@ -19,6 +19,7 @@ describe('Conversations', () => {
       user2.account.address,
     ])
     expect(conversation).toBeDefined()
+    expect(client1.conversations.get(conversation.id)?.id).toBe(conversation.id)
     expect(conversation.id).toBeDefined()
     expect(conversation.createdAt).toBeDefined()
     expect(conversation.createdAtNs).toBeDefined()
@@ -75,6 +76,12 @@ describe('Conversations', () => {
       }
     }
     stream.stop()
+    expect(client3.conversations.get(conversation1.id)?.id).toBe(
+      conversation1.id
+    )
+    expect(client3.conversations.get(conversation2.id)?.id).toBe(
+      conversation2.id
+    )
   })
 
   it('should stream all messages', async () => {
diff --git a/yarn.lock b/yarn.lock
index 637ae849..079bfe16 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2863,6 +2863,15 @@ __metadata:
   languageName: node
   linkType: hard
 
+"@xmtp/content-type-primitives@npm:^1.0.1":
+  version: 1.0.1
+  resolution: "@xmtp/content-type-primitives@npm:1.0.1"
+  dependencies:
+    "@xmtp/proto": "npm:^3.61.1"
+  checksum: 10/656826cda74328e3079c7f5937eeb694260bd68a66090303fdf6abf4c54c8bbf924064eb6895b9e66addee1269779dfe1c3f0e836fcd8857f784c5645c7b7bf5
+  languageName: node
+  linkType: hard
+
 "@xmtp/mls-client-bindings-node@npm:^0.0.4":
   version: 0.0.4
   resolution: "@xmtp/mls-client-bindings-node@npm:0.0.4"
@@ -2881,9 +2890,10 @@ __metadata:
     "@typescript-eslint/eslint-plugin": "npm:^7.8.0"
     "@typescript-eslint/parser": "npm:^7.8.0"
     "@vitest/coverage-v8": "npm:^1.6.0"
+    "@xmtp/content-type-primitives": "npm:^1.0.1"
     "@xmtp/mls-client-bindings-node": "npm:^0.0.4"
     "@xmtp/proto": "npm:^3.61.1"
-    "@xmtp/xmtp-js": "npm:^11.6.2"
+    "@xmtp/xmtp-js": "workspace:^"
     eslint: "npm:^8.57.0"
     eslint-config-prettier: "npm:^9.1.0"
     eslint-config-standard: "npm:^17.1.0"
@@ -2963,7 +2973,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@xmtp/xmtp-js@npm:^11.6.2, @xmtp/xmtp-js@workspace:packages/js-sdk":
+"@xmtp/xmtp-js@workspace:^, @xmtp/xmtp-js@workspace:packages/js-sdk":
   version: 0.0.0-use.local
   resolution: "@xmtp/xmtp-js@workspace:packages/js-sdk"
   dependencies: