From 9b34d357d40043a816d6e72a15d99b53a15b43a0 Mon Sep 17 00:00:00 2001
From: Samuel Newman <mozzius@protonmail.com>
Date: Fri, 10 Jul 2026 12:43:04 +0300
Subject: [PATCH] Lazy load @ipld/dag-cbor in computeCid (#11099)

Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
---
 src/lib/api/index.ts | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/lib/api/index.ts b/src/lib/api/index.ts
index 5a278aeba4..69cc2bf03e 100644
--- a/src/lib/api/index.ts
+++ b/src/lib/api/index.ts
@@ -16,7 +16,6 @@ import {
   RichText,
 } from '@atproto/api'
 import {TID} from '@atproto/common-web'
-import * as dcbor from '@ipld/dag-cbor'
 import {t} from '@lingui/core/macro'
 import {type QueryClient} from '@tanstack/react-query'
 import {sha256} from 'js-sha256'
@@ -505,6 +504,12 @@ const mf_sha256 = Hasher.from({
 })
 
 async function computeCid(record: AppBskyFeedPost.Record): Promise<string> {
+  /*
+   * Lazily loaded since it's only needed when posting a thread, and its
+   * `cborg` dependency is ~190KB that would otherwise be in the initial
+   * web bundle.
+   */
+  const dcbor = await import('@ipld/dag-cbor')
   // IMPORTANT: `prepareObject` prepares the record to be hashed by removing
   // fields with undefined value, and converting BlobRef instances to the
   // right IPLD representation.