Replace lru-cache dep with light util

app/components/Avatar.tsx

@@ -1,8 +1,8 @@
 import clsx from "clsx";
-import { LRUCache } from "lru-cache";
 import * as React from "react";
 import type { Tables } from "~/db/tables";
 import { useHydrated } from "~/hooks/useHydrated";
+import { LRUCache } from "~/modules/cache";
 import { BLANK_IMAGE_URL, discordAvatarUrl } from "~/utils/urls";
 import styles from "./Avatar.module.css";
 

app/modules/cache/index.test.ts

@@ -0,0 +1,67 @@
+import { describe, expect, it } from "vitest";
+import { LRUCache } from "./index";
+
+describe("LRUCache", () => {
+	it("stores and retrieves values", () => {
+		const cache = new LRUCache<string, number>({ max: 2 });
+		cache.set("a", 1);
+
+		expect(cache.get("a")).toBe(1);
+		expect(cache.has("a")).toBe(true);
+	});
+
+	it("returns undefined for missing keys", () => {
+		const cache = new LRUCache<string, number>({ max: 2 });
+
+		expect(cache.get("missing")).toBeUndefined();
+		expect(cache.has("missing")).toBe(false);
+	});
+
+	it("evicts the least recently used entry once over capacity", () => {
+		const cache = new LRUCache<string, number>({ max: 2 });
+		cache.set("a", 1);
+		cache.set("b", 2);
+		cache.set("c", 3);
+
+		expect(cache.has("a")).toBe(false);
+		expect(cache.get("b")).toBe(2);
+		expect(cache.get("c")).toBe(3);
+	});
+
+	it("counts reads as recent use", () => {
+		const cache = new LRUCache<string, number>({ max: 2 });
+		cache.set("a", 1);
+		cache.set("b", 2);
+		cache.get("a");
+		cache.set("c", 3);
+
+		expect(cache.has("a")).toBe(true);
+		expect(cache.has("b")).toBe(false);
+	});
+
+	it("updates value without growing past capacity on re-set", () => {
+		const cache = new LRUCache<string, number>({ max: 2 });
+		cache.set("a", 1);
+		cache.set("a", 2);
+
+		expect(cache.get("a")).toBe(2);
+	});
+
+	it("deletes a single entry", () => {
+		const cache = new LRUCache<string, number>({ max: 2 });
+		cache.set("a", 1);
+		cache.delete("a");
+
+		expect(cache.has("a")).toBe(false);
+	});
+
+	it("clears all entries", () => {
+		const cache = new LRUCache<string, number>({ max: 2 });
+		cache.set("a", 1);
+		cache.set("b", 2);
+		cache.clear();
+
+		expect(cache.has("a")).toBe(false);
+		expect(cache.has("b")).toBe(false);
+	});
+});

app/modules/cache/index.ts

@@ -0,0 +1,48 @@
+/**
+ * A lightweight least-recently-used cache backed by a `Map`. Once `max` entries
+ * are stored, inserting a new key evicts the least recently used one. Reading a
+ * key via `get` marks it as most recently used.
+ */
+export class LRUCache<K, V> {
+	private readonly max: number;
+	private readonly map = new Map<K, V>();
+
+	constructor({ max }: { max: number }) {
+		this.max = max;
+	}
+
+	get(key: K): V | undefined {
+		if (!this.map.has(key)) return undefined;
+
+		const value = this.map.get(key) as V;
+		this.map.delete(key);
+		this.map.set(key, value);
+
+		return value;
+	}
+
+	has(key: K): boolean {
+		return this.map.has(key);
+	}
+
+	set(key: K, value: V): void {
+		if (this.map.has(key)) {
+			this.map.delete(key);
+		}
+
+		this.map.set(key, value);
+
+		if (this.map.size > this.max) {
+			const oldest = this.map.keys().next().value as K;
+			this.map.delete(oldest);
+		}
+	}
+
+	delete(key: K): void {
+		this.map.delete(key);
+	}
+
+	clear(): void {
+		this.map.clear();
+	}
+}

app/utils/cache.server.ts

@@ -1,5 +1,5 @@
 import type { CacheEntry } from "@epic-web/cachified";
-import { LRUCache } from "lru-cache";
+import { LRUCache } from "~/modules/cache";
 
 declare global {
 	// This preserves the LRU cache during development

package.json

@@ -68,7 +68,6 @@
 		"isbot": "5.1.40",
 		"jsoncrush": "1.1.8",
 		"kysely": "0.29.0",
-		"lru-cache": "11.5.1",
 		"lucide-react": "1.17.0",
 		"markdown-to-jsx": "9.8.1",
 		"nanoid": "5.1.11",

pnpm-lock.yaml

@@ -102,9 +102,6 @@ importers:
       kysely:
         specifier: 0.29.0
         version: 0.29.0(patch_hash=6f395b25414c1ef852485fa3a03d2d521816064697d8c4bff337e2b24d19daa6)
-      lru-cache:
-        specifier: 11.5.1
-        version: 11.5.1
       lucide-react:
         specifier: 1.17.0
         version: 1.17.0(react@19.2.7)