diff --git a/.jules/bolt.md b/.jules/bolt.md
index 91541609..d4bdfa93 100644
--- a/.jules/bolt.md
+++ b/.jules/bolt.md
@@ -9,3 +9,7 @@
 
 **Learning:** Using `on:keyup` for search input debouncing triggers unnecessary API calls on navigation keys (arrows, home, end) and misses changes from paste/cut. Svelte's reactive statements `$: debounce(value)` provide a robust, declarative way to trigger debouncing only when the value actually changes.
 **Action:** Replace `on:keyup` handlers with reactive statements for input debouncing to improve performance and correctness.
+
+## 2026-06-27 - O(N*M) Array Filtering and Static Mappings
+**Learning:** Using `Array.prototype.includes()` inside `Array.prototype.filter()` introduces O(N*M) complexity which is detrimental for large datasets (e.g. comparing `owners` against `voters`). Additionally, static configurations like `metaNamesSdk.config.byoc` should be mapped at the module level rather than on every request.
+**Action:** Precompute an O(1) `Set` before filtering to optimize array comparisons to O(N). Move static module configurations to module-level sets or constants.
diff --git a/src/routes/api/proposals/voters/add/+server.ts b/src/routes/api/proposals/voters/add/+server.ts
index 62f2caf8..584e9ef8 100644
--- a/src/routes/api/proposals/voters/add/+server.ts
+++ b/src/routes/api/proposals/voters/add/+server.ts
@@ -22,8 +22,10 @@ export async function GET() {
 			.get('voters')
 			?.setValue()
 			.values.map((voter) => voter.addressValue().value.toString('hex')) ?? [];
+	const votersSet = new Set(voters);
 
-	const newVoters = owners.filter((owner) => !voters.includes(owner)).slice(0, 50);
+	// Optimizing O(N*M) inclusion check to O(N) Set lookup
+	const newVoters = owners.filter((owner) => !votersSet.has(owner)).slice(0, 50);
 	if (newVoters.length === 0) return json({ newVoters }, { status: 200 });
 
 	const votingContract = await metaNamesSdk.contractRepository.getContract({
diff --git a/src/routes/api/proposals/voters/remove/+server.ts b/src/routes/api/proposals/voters/remove/+server.ts
index d024e90f..0da06ab3 100644
--- a/src/routes/api/proposals/voters/remove/+server.ts
+++ b/src/routes/api/proposals/voters/remove/+server.ts
@@ -19,13 +19,15 @@ export async function GET() {
 		return json({ error: 'Voting has ended' }, { status: 400 });
 
 	const owners = await metaNamesSdk.domainRepository.getOwners();
+	const ownersSet = new Set(owners);
 	const voters =
 		fields
 			.get('voters')
 			?.setValue()
 			.values.map((voter) => voter.addressValue().value.toString('hex')) ?? [];
 
-	const votersToRemove = voters.filter((voter) => !owners.includes(voter)).slice(0, 50);
+	// Optimizing O(N*M) inclusion check to O(N) Set lookup
+	const votersToRemove = voters.filter((voter) => !ownersSet.has(voter)).slice(0, 50);
 	if (votersToRemove.length === 0) return json({ newVoters: votersToRemove }, { status: 200 });
 
 	const votingContract = await metaNamesSdk.contractRepository.getContract({
diff --git a/src/routes/api/register/[name]/fees/[coin]/+server.ts b/src/routes/api/register/[name]/fees/[coin]/+server.ts
index af646a01..9e565e8d 100644
--- a/src/routes/api/register/[name]/fees/[coin]/+server.ts
+++ b/src/routes/api/register/[name]/fees/[coin]/+server.ts
@@ -1,12 +1,13 @@
 import { apiError, handleError, metaNamesSdk } from '$lib/server';
 import type { BYOCSymbol } from '@metanames/sdk';
 import { json } from '@sveltejs/kit';
-import type { DomainFeesResponse } from 'src/lib/types';
+
+// Precomputing the valid coins at module level to avoid recalculation per request
+const validCoinsSet = new Set(metaNamesSdk.config.byoc.map((byoc) => byoc.symbol.toString()));
 
 export async function GET({ params: { name, coin } }) {
 	return handleError(async () => {
-		const validCoins = metaNamesSdk.config.byoc.map((byoc) => byoc.symbol.toString());
-		if (!validCoins.includes(coin)) return apiError('Invalid coin');
+		if (!validCoinsSet.has(coin)) return apiError('Invalid coin');
 
 		const normalizedDomain = metaNamesSdk.domainRepository.domainValidator.normalize(name);
 		const domainFees = await metaNamesSdk.domainRepository.calculateMintFees(