diff --git a/scripts/build.copy-workers.mjs b/scripts/build.copy-workers.mjs
index 22be97875..51bd3cd7c 100644
--- a/scripts/build.copy-workers.mjs
+++ b/scripts/build.copy-workers.mjs
@@ -9,6 +9,8 @@ await cp(
 		filter: (source) => extname(source) !== '.map'
 	},
 	(err) => {
+		// TODO: Remove ESLint exception and use nullish checks
+		// eslint-disable-next-line local-rules/use-nullish-checks
 		if (err === null) {
 			return;
 		}
diff --git a/scripts/build.tokens.ckerc20.mjs b/scripts/build.tokens.ckerc20.mjs
index 6cc73f8c0..71d54291f 100755
--- a/scripts/build.tokens.ckerc20.mjs
+++ b/scripts/build.tokens.ckerc20.mjs
@@ -4,7 +4,7 @@ import { AnonymousIdentity } from '@dfinity/agent';
 import { CkETHOrchestratorCanister } from '@dfinity/cketh';
 import { IcrcLedgerCanister } from '@dfinity/ledger-icrc';
 import { Principal } from '@dfinity/principal';
-import { createAgent, fromNullable, isNullish, jsonReplacer } from '@dfinity/utils';
+import { createAgent, fromNullable, isNullish, jsonReplacer, nonNullish } from '@dfinity/utils';
 import { existsSync, writeFileSync } from 'node:fs';
 import { join } from 'node:path';
 
@@ -74,7 +74,7 @@ const buildOrchestratorInfo = async (orchestratorId) => {
 
 	const assertUniqueTokenSymbol = Object.values(tokens).find((value) => value.length > 1);
 
-	if (assertUniqueTokenSymbol !== undefined) {
+	if (nonNullish(assertUniqueTokenSymbol)) {
 		throw new Error(
 			`More than one pair of ledger and index canisters were used for the token symbol ${assertUniqueTokenSymbol}.`
 		);
diff --git a/src/frontend/src/icp-eth/services/cketh.services.ts b/src/frontend/src/icp-eth/services/cketh.services.ts
index 0e04a7e88..2568f56c3 100644
--- a/src/frontend/src/icp-eth/services/cketh.services.ts
+++ b/src/frontend/src/icp-eth/services/cketh.services.ts
@@ -23,6 +23,7 @@ export const loadCkEthMinterInfo = async ({
 	const minterInfoInStore = get(ckEthMinterInfoStore);
 
 	// We try to load only once per session the helpers (ckETH and ckErc20) contract addresses
+	// eslint-disable-next-line local-rules/use-nullish-checks -- We want to check for not-undefined values but null is allowed
 	if (minterInfoInStore?.[tokenId] !== undefined) {
 		return;
 	}
diff --git a/src/frontend/src/lib/utils/route.utils.ts b/src/frontend/src/lib/utils/route.utils.ts
index d52b3ae57..769e37242 100644
--- a/src/frontend/src/lib/utils/route.utils.ts
+++ b/src/frontend/src/lib/utils/route.utils.ts
@@ -1,3 +1,5 @@
+import { nonNullish } from '@dfinity/utils';
+
 /**
  * Update browser URL. To be use only for really particular use case that do not include navigation and loading data.
  */
@@ -15,6 +17,6 @@ export const replaceHistory = (url: URL) => {
  * Source: https://stackoverflow.com/a/6825002/5404186
  */
 const supportsHistory = (): boolean =>
-	window.history !== undefined &&
+	nonNullish(window.history) &&
 	'pushState' in window.history &&
 	typeof window.history.pushState !== 'undefined';