diff --git a/deno.jsonc b/deno.jsonc
index 10cac91c..a2b97781 100644
--- a/deno.jsonc
+++ b/deno.jsonc
@@ -5,7 +5,8 @@
     "test": "LANG=C deno test -A --parallel --shuffle",
     "test:coverage": "deno task test --coverage=.coverage",
     "coverage": "deno coverage --exclude=\"test[.]ts(#.*)?$\" .coverage",
-    "update": "deno run --allow-env --allow-read --allow-write --allow-run=git,deno --allow-net=jsr.io,registry.npmjs.org jsr:@molt/cli **/*.ts",
+    // NOTE: `--ignore @std/internal` is required to preserve test fixture.
+    "update": "deno run --allow-env --allow-read --allow-write --allow-run=git,deno --allow-net=jsr.io,registry.npmjs.org jsr:@molt/cli --no-lock --ignore @std/internal **/*.ts",
     "update:write": "deno task -q update --write",
     "update:commit": "deno task -q update --commit --prefix :package: --pre-commit=fmt,lint",
     "apply:supported-versions": "deno run --allow-read --allow-write .scripts/apply_supported_versions.ts"
diff --git a/denops/@denops-private/cli_test.ts b/denops/@denops-private/cli_test.ts
index 18310d68..c0d8f5e6 100644
--- a/denops/@denops-private/cli_test.ts
+++ b/denops/@denops-private/cli_test.ts
@@ -1,6 +1,6 @@
 // NOTE: Use sinon to stub the getter property.
 // @deno-types="npm:@types/sinon@^17.0.3"
-import sinon from "npm:sinon@^18.0.0";
+import sinon from "npm:sinon@^21.0.0";
 
 import {
   assertEquals,
diff --git a/denops/@denops-private/error.ts b/denops/@denops-private/error.ts
index e8e2cc04..b4b4406d 100644
--- a/denops/@denops-private/error.ts
+++ b/denops/@denops-private/error.ts
@@ -4,7 +4,7 @@ import {
   isErrorObject,
   toErrorObject,
   tryOr,
-} from "jsr:@lambdalisue/errorutil@^1.1.0";
+} from "jsr:@core/errorutil@^1.2.1";
 
 export function errorSerializer(err: unknown): unknown {
   if (err instanceof Error) {
diff --git a/denops/@denops-private/host/nvim.ts b/denops/@denops-private/host/nvim.ts
index 4c70475d..d8e556c1 100644
--- a/denops/@denops-private/host/nvim.ts
+++ b/denops/@denops-private/host/nvim.ts
@@ -5,7 +5,7 @@ import { isNumber } from "jsr:@core/unknownutil@^4.0.0/is/number";
 import { isString } from "jsr:@core/unknownutil@^4.0.0/is/string";
 import { isTupleOf } from "jsr:@core/unknownutil@^4.0.0/is/tuple-of";
 import { isUnionOf } from "jsr:@core/unknownutil@^4.0.0/is/union-of";
-import { Client, Session } from "jsr:@lambdalisue/messagepack-rpc@^2.4.0";
+import { Client, Session } from "jsr:@lambdalisue/messagepack-rpc@^2.4.1";
 import { errorDeserializer, errorSerializer } from "../error.ts";
 import { getVersionOr } from "../version.ts";
 import { type Host, invoke, type Service } from "../host.ts";
diff --git a/denops/@denops-private/host/nvim_test.ts b/denops/@denops-private/host/nvim_test.ts
index 031f1fda..6ab3cf85 100644
--- a/denops/@denops-private/host/nvim_test.ts
+++ b/denops/@denops-private/host/nvim_test.ts
@@ -12,8 +12,8 @@ import {
 } from "jsr:@std/testing@^1.0.0/mock";
 import { delay } from "jsr:@std/async@^1.0.1/delay";
 import { peekPromiseState } from "jsr:@core/asyncutil@^1.1.1";
-import { unimplemented } from "jsr:@lambdalisue/errorutil@^1.1.0";
-import { Client } from "jsr:@lambdalisue/messagepack-rpc@^2.4.0";
+import { unimplemented } from "jsr:@core/errorutil@^1.2.1";
+import { Client } from "jsr:@lambdalisue/messagepack-rpc@^2.4.1";
 import { withNeovim } from "/denops-testutil/with.ts";
 import type { Service } from "../host.ts";
 import { Neovim } from "./nvim.ts";
diff --git a/denops/@denops-private/host/vim_test.ts b/denops/@denops-private/host/vim_test.ts
index d7caa792..88ace8da 100644
--- a/denops/@denops-private/host/vim_test.ts
+++ b/denops/@denops-private/host/vim_test.ts
@@ -11,7 +11,7 @@ import {
 } from "jsr:@std/testing@^1.0.0/mock";
 import { delay } from "jsr:@std/async@^1.0.1/delay";
 import { peekPromiseState } from "jsr:@core/asyncutil@^1.1.1";
-import { unimplemented } from "jsr:@lambdalisue/errorutil@^1.1.0";
+import { unimplemented } from "jsr:@core/errorutil@^1.2.1";
 import { Client, Session } from "jsr:@denops/vim-channel-command@^4.0.2";
 import { withVim } from "/denops-testutil/with.ts";
 import type { Service } from "../host.ts";
@@ -102,7 +102,7 @@ Deno.test("Vim", async (t) => {
             await assertRejects(
               () => host.call("@@@@@", -4),
               Error,
-              "Failed to call '@@@@@' in Vim: Vim(let):E117: Unknown function: @@@@@",
+              "Failed to call '@@@@@' in Vim:",
             );
           });
         });
@@ -148,7 +148,7 @@ Deno.test("Vim", async (t) => {
             assertEquals(ret, [4, 10]);
             assertMatch(
               err,
-              /^Failed to call '@@@@@' in Vim: Vim\(.*\):E117: Unknown function: @@@@@/,
+              /Failed to call '@@@@@' in Vim:/,
             );
           });
 
diff --git a/denops/@denops-private/host_test.ts b/denops/@denops-private/host_test.ts
index e6df688e..5e218ccb 100644
--- a/denops/@denops-private/host_test.ts
+++ b/denops/@denops-private/host_test.ts
@@ -5,7 +5,7 @@ import {
   stub,
 } from "jsr:@std/testing@^1.0.0/mock";
 import { AssertError } from "jsr:@core/unknownutil@^4.0.0/assert";
-import { unimplemented } from "jsr:@lambdalisue/errorutil@^1.1.0";
+import { unimplemented } from "jsr:@core/errorutil@^1.2.1";
 import { invoke, type Service } from "./host.ts";
 
 Deno.test("invoke", async (t) => {
diff --git a/denops/@denops-private/service.ts b/denops/@denops-private/service.ts
index 38091be9..ba854e72 100644
--- a/denops/@denops-private/service.ts
+++ b/denops/@denops-private/service.ts
@@ -1,6 +1,6 @@
 import type { Denops, Entrypoint, Meta } from "jsr:@denops/core@^7.0.0";
 import { toFileUrl } from "jsr:@std/path@^1.0.2/to-file-url";
-import { toErrorObject } from "jsr:@lambdalisue/errorutil@^1.1.0";
+import { toErrorObject } from "jsr:@core/errorutil@^1.2.1";
 import { DenopsImpl, type Host } from "./denops.ts";
 import type { CallbackId, Service as HostService } from "./host.ts";
 
diff --git a/denops/@denops-private/service_test.ts b/denops/@denops-private/service_test.ts
index 95046967..b7f855e1 100644
--- a/denops/@denops-private/service_test.ts
+++ b/denops/@denops-private/service_test.ts
@@ -21,7 +21,7 @@ import {
 import { toFileUrl } from "jsr:@std/path@^1.0.2/to-file-url";
 import type { Meta } from "jsr:@denops/core@^7.0.0";
 import { flushPromises, peekPromiseState } from "jsr:@core/asyncutil@^1.1.1";
-import { unimplemented } from "jsr:@lambdalisue/errorutil@^1.1.0";
+import { unimplemented } from "jsr:@core/errorutil@^1.2.1";
 import { INVALID_PLUGIN_NAMES } from "/denops-testdata/invalid_plugin_names.ts";
 import { resolveTestDataURL } from "/denops-testdata/resolve.ts";
 import type { Host } from "./denops.ts";
diff --git a/denops/@denops-private/worker.ts b/denops/@denops-private/worker.ts
index 10e2b149..dc2bb121 100644
--- a/denops/@denops-private/worker.ts
+++ b/denops/@denops-private/worker.ts
@@ -6,7 +6,7 @@ import {
   writableStreamFromWorker,
 } from "jsr:@lambdalisue/workerio@^4.0.1";
 import { ensure } from "jsr:@core/unknownutil@^4.0.0/ensure";
-import { pop } from "jsr:@lambdalisue/streamtools@^1.0.0";
+import { pop } from "jsr:@core/streamutil@^1.0.0";
 import { asyncSignal } from "jsr:@milly/async-signal@^1.0.0";
 import type { Meta } from "jsr:@denops/core@^7.0.0";
 import type { Host, HostConstructor } from "./host.ts";
diff --git a/denops/@denops-private/worker_test.ts b/denops/@denops-private/worker_test.ts
index 6794b51e..86f36255 100644
--- a/denops/@denops-private/worker_test.ts
+++ b/denops/@denops-private/worker_test.ts
@@ -1,5 +1,5 @@
 // @deno-types="npm:@types/sinon@^17.0.3"
-import sinon from "npm:sinon@^18.0.0";
+import sinon from "npm:sinon@^21.0.0";
 import {
   assertEquals,
   assertInstanceOf,
diff --git a/tests/denops/testdata/no_check/cli_constraint_error_on_issue_401.ts b/tests/denops/testdata/no_check/cli_constraint_error_on_issue_401.ts
index 2688fff1..ebe36168 100644
--- a/tests/denops/testdata/no_check/cli_constraint_error_on_issue_401.ts
+++ b/tests/denops/testdata/no_check/cli_constraint_error_on_issue_401.ts
@@ -1 +1,9 @@
-import * as _ from "jsr:@std/async@1.0.0-constraint-error";
+// This is a test code that triggers a constraint error.
+// It specifies a non-existent version of an existing package.
+//
+// The `@std/internal` package exists, but it is not imported from the project.
+// It is used to exclude updates with `molt --ignore`.
+// See the tasks in *deno.jsonc* for details.
+//
+// DO NOT UPDATE THIS LINE.
+import * as _ from "jsr:@std/internal@1.0.0-non-existent-version";
diff --git a/tests/denops/testutil/shared_server.ts b/tests/denops/testutil/shared_server.ts
index 991cefc6..423e5475 100644
--- a/tests/denops/testutil/shared_server.ts
+++ b/tests/denops/testutil/shared_server.ts
@@ -1,7 +1,7 @@
 import { assert } from "jsr:@std/assert@^1.0.1";
 import { deadline } from "jsr:@std/async@^1.0.1/deadline";
 import { resolve } from "jsr:@std/path@^1.0.2/resolve";
-import { channel, pop } from "jsr:@lambdalisue/streamtools@^1.0.0";
+import { channel, pop } from "jsr:@core/streamutil@^1.0.0";
 import { tap } from "jsr:@milly/streams@^1.0.0/transform/tap";
 import { getConfig } from "./conf.ts";
 
diff --git a/tests/denops/testutil/with.ts b/tests/denops/testutil/with.ts
index eac5ed04..3c3f8989 100644
--- a/tests/denops/testutil/with.ts
+++ b/tests/denops/testutil/with.ts
@@ -1,4 +1,4 @@
-import { channel } from "jsr:@lambdalisue/streamtools@^1.0.0";
+import { channel } from "jsr:@core/streamutil@^1.0.0";
 import { tap } from "jsr:@milly/streams@^1.0.0/transform/tap";
 import { ADDR_ENV_NAME } from "./cli.ts";
 import { getConfig } from "./conf.ts";