From c474524fc4cc5f2903ccd84a4249bca4e3a4a45d Mon Sep 17 00:00:00 2001
From: Marzooqa Kather <marzooqakather498@bitgo.com>
Date: Tue, 28 Apr 2026 10:35:08 +0000
Subject: [PATCH] fix(sdk-lib-mpc): use @bitgo/wasm-mps/web in browser for
 EdDSA DKG
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In browsers (webpack), importing @bitgo/wasm-mps resolves to the
--target bundler ESM build which has a race condition between
webpack's async WASM instantiation and __wbg_set_wasm being called.
This causes wasm.ed25519_dkg_round0_process to be undefined when
initDkg() runs.

Mirror the ECDSA pattern in ecdsa-dkls/dkg.ts: detect browser via
`typeof window !== 'undefined'` (excluding Electron via window.process
checks), then use @bitgo/wasm-mps/web which exposes an explicit
init() function — guaranteed ready after await.

Adds a local .d.ts shim for @bitgo/wasm-mps/web until WCI-250
publishes the ./web subpath export with its own types.

Ticket: WCI-251
---
 modules/sdk-lib-mpc/package.json             |  2 +-
 modules/sdk-lib-mpc/src/tss/eddsa-mps/dkg.ts | 20 ++++++++++++++++++--
 webpack/bitgojs.config.js                    |  1 +
 yarn.lock                                    |  8 ++++----
 4 files changed, 24 insertions(+), 7 deletions(-)

diff --git a/modules/sdk-lib-mpc/package.json b/modules/sdk-lib-mpc/package.json
index 6bf73ee07b..5fd84ba37d 100644
--- a/modules/sdk-lib-mpc/package.json
+++ b/modules/sdk-lib-mpc/package.json
@@ -36,7 +36,7 @@
     ]
   },
   "dependencies": {
-    "@bitgo/wasm-mps": "1.7.0",
+    "@bitgo/wasm-mps": "1.8.1",
     "@noble/curves": "1.8.1",
     "@silencelaboratories/dkls-wasm-ll-node": "1.2.0-pre.4",
     "@silencelaboratories/dkls-wasm-ll-web": "1.2.0-pre.4",
diff --git a/modules/sdk-lib-mpc/src/tss/eddsa-mps/dkg.ts b/modules/sdk-lib-mpc/src/tss/eddsa-mps/dkg.ts
index 6845f78a6e..d59e047235 100644
--- a/modules/sdk-lib-mpc/src/tss/eddsa-mps/dkg.ts
+++ b/modules/sdk-lib-mpc/src/tss/eddsa-mps/dkg.ts
@@ -3,7 +3,9 @@ import { encode } from 'cbor-x';
 import crypto from 'crypto';
 import { DeserializedMessage, DeserializedMessages, DkgState, EddsaReducedKeyShare } from './types';
 
-type WasmMps = typeof import('@bitgo/wasm-mps');
+type NodeWasmer = typeof import('@bitgo/wasm-mps');
+type WebWasmer = typeof import('@bitgo/wasm-mps/web');
+type WasmMps = NodeWasmer | WebWasmer;
 
 /**
  * EdDSA Distributed Key Generation (DKG) implementation using @bitgo/wasm-mps.
@@ -53,7 +55,21 @@ export class DKG {
 
   private async loadWasmMps(): Promise<void> {
     if (!this.wasmMps) {
-      this.wasmMps = await import('@bitgo/wasm-mps');
+      if (
+        typeof window !== 'undefined' &&
+        /* checks for electron processes */
+        !window.process &&
+        !window.process?.['type']
+      ) {
+        // Browser: web build has explicit init() — guaranteed ready after await
+        // eslint-disable-next-line import/no-internal-modules -- @bitgo/wasm-mps exposes environment-specific subpath exports.
+        const webWasm = await import('@bitgo/wasm-mps/web');
+        await webWasm.default();
+        this.wasmMps = webWasm;
+      } else {
+        // Node.js: dynamic import() rewritten to require() by tsc → CJS build → readFileSync
+        this.wasmMps = await import('@bitgo/wasm-mps');
+      }
     }
   }
 
diff --git a/webpack/bitgojs.config.js b/webpack/bitgojs.config.js
index 94fbfec112..b40af33464 100644
--- a/webpack/bitgojs.config.js
+++ b/webpack/bitgojs.config.js
@@ -22,6 +22,7 @@ module.exports = {
       '@bitgo/wasm-ton': path.resolve('../../node_modules/@bitgo/wasm-ton/dist/esm/js/index.js'),
       '@bitgo/wasm-utxo': path.resolve('../../node_modules/@bitgo/wasm-utxo/dist/esm/js/index.js'),
       '@bitgo/wasm-solana': path.resolve('../../node_modules/@bitgo/wasm-solana/dist/esm/js/index.js'),
+      '@bitgo/wasm-mps/web': path.resolve('../../node_modules/@bitgo/wasm-mps/dist/web/js/wasm/wasm_mps.js'),
       '@bitgo/wasm-mps': path.resolve('../../node_modules/@bitgo/wasm-mps/dist/esm/js/wasm/wasm_mps.js'),
       '@bitgo/utxo-ord': path.resolve('../utxo-ord/dist/esm/index.js'),
     },
diff --git a/yarn.lock b/yarn.lock
index b7906a70c8..797232913e 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1015,10 +1015,10 @@
   resolved "https://registry.npmjs.org/@bitgo/wasm-dot/-/wasm-dot-1.7.0.tgz"
   integrity sha512-KoXavJvyDHlEN+sWcigbgxYJtdFaU7gS0EkYQbNH4npVjNlzo6rL6gwjyWbyOy7oEs65DhpJ9vY5kRbE/bKiTQ==
 
-"@bitgo/wasm-mps@1.7.0":
-  version "1.7.0"
-  resolved "https://registry.npmjs.org/@bitgo/wasm-mps/-/wasm-mps-1.7.0.tgz#e7ebca1afd2df757e69c5cdac702d6a06156867c"
-  integrity sha512-SNO7as4UvnE2ptDXp1oUXjABA8Y3/71lgVpAQyAGSfSaURjz4rG19+JZR54GBRIaA6hvUPr029b4gFyqoZPcgg==
+"@bitgo/wasm-mps@1.8.1":
+  version "1.8.1"
+  resolved "https://registry.npmjs.org/@bitgo/wasm-mps/-/wasm-mps-1.8.1.tgz#946673f5845696cdcf744f8122fd1fc2be3edce1"
+  integrity sha512-CV8EXYc1BGYtXdCRDxJ5h04nj/LpMgu3VlkfowlodI6UKcj1zotAvk4OMIdgiPPbKVr1l+xibHDXZYx/uf3rnw==
 
 "@bitgo/wasm-solana@^2.6.0":
   version "2.6.0"