diff --git a/src/config/cache.ts b/src/config/cache.ts
index 916047e..584ff69 100644
--- a/src/config/cache.ts
+++ b/src/config/cache.ts
@@ -1,47 +1,54 @@
-import { config } from "dotenv";
 import { Redis } from "ioredis";
-
-config();
+import { env } from "./env.js";
 
 export class AniwatchAPICache {
-    private _client: Redis | null;
+    private static instance: AniwatchAPICache | null = null;
+
+    private client: Redis | null;
     public isOptional: boolean = true;
 
     static DEFAULT_CACHE_EXPIRY_SECONDS = 60 as const;
     static CACHE_EXPIRY_HEADER_NAME = "X-ANIWATCH-CACHE-EXPIRY" as const;
 
     constructor() {
-        const redisConnURL = process.env?.ANIWATCH_API_REDIS_CONN_URL;
+        const redisConnURL = env.ANIWATCH_API_REDIS_CONN_URL;
         this.isOptional = !Boolean(redisConnURL);
-        this._client = this.isOptional ? null : new Redis(String(redisConnURL));
+        this.client = this.isOptional ? null : new Redis(String(redisConnURL));
     }
 
-    set(key: string | Buffer, value: string | Buffer | number) {
-        if (this.isOptional) return;
-        return this._client?.set(key, value);
+    static getInstance() {
+        if (!AniwatchAPICache.instance) {
+            AniwatchAPICache.instance = new AniwatchAPICache();
+        }
+        return AniwatchAPICache.instance;
     }
 
-    get(key: string | Buffer) {
-        if (this.isOptional) return;
-        return this._client?.get(key);
-    }
+    // set(key: string | Buffer, value: string | Buffer | number) {
+    //     if (this.isOptional) return;
+    //     return this.client?.set(key, value);
+    // }
+
+    // get(key: string | Buffer) {
+    //     if (this.isOptional) return;
+    //     return this.client?.get(key);
+    // }
 
     /**
      * @param expirySeconds set to 60 by default
      */
     async getOrSet<T>(
-        setCB: () => Promise<T>,
+        dataGetter: () => Promise<T>,
         key: string | Buffer,
         expirySeconds: number = AniwatchAPICache.DEFAULT_CACHE_EXPIRY_SECONDS
     ) {
         const cachedData = this.isOptional
             ? null
-            : (await this._client?.get(key)) || null;
+            : (await this.client?.get?.(key)) || null;
         let data = JSON.parse(String(cachedData)) as T;
 
         if (!data) {
-            data = await setCB();
-            await this._client?.set(
+            data = await dataGetter();
+            await this.client?.set?.(
                 key,
                 JSON.stringify(data),
                 "EX",
@@ -52,4 +59,4 @@ export class AniwatchAPICache {
     }
 }
 
-export const cache = new AniwatchAPICache();
+export const cache = AniwatchAPICache.getInstance();
diff --git a/src/config/cors.ts b/src/config/cors.ts
index 6d6e138..f6b5f25 100644
--- a/src/config/cors.ts
+++ b/src/config/cors.ts
@@ -1,17 +1,15 @@
-import { config } from "dotenv";
 import { cors } from "hono/cors";
+import { env } from "./env.js";
 
-config();
+const DEFAULT_ALLOWED_ORIGINS = ["http://localhost:4000", "*"];
 
-const allowedOrigins = process.env.ANIWATCH_API_CORS_ALLOWED_ORIGINS
-  ? process.env.ANIWATCH_API_CORS_ALLOWED_ORIGINS.split(",")
-  : ["http://localhost:4000", "*"];
+const allowedOrigins = env.ANIWATCH_API_CORS_ALLOWED_ORIGINS
+    ? env.ANIWATCH_API_CORS_ALLOWED_ORIGINS.split(",")
+    : DEFAULT_ALLOWED_ORIGINS;
 
-const corsConfig = cors({
-  allowMethods: ["GET"],
-  maxAge: 600,
-  credentials: true,
-  origin: allowedOrigins,
+export const corsConfig = cors({
+    allowMethods: ["GET"],
+    maxAge: 600,
+    credentials: true,
+    origin: allowedOrigins,
 });
-
-export default corsConfig;
diff --git a/src/config/errorHandler.ts b/src/config/errorHandler.ts
index d6f3193..36f57c3 100644
--- a/src/config/errorHandler.ts
+++ b/src/config/errorHandler.ts
@@ -1,27 +1,28 @@
 import { HiAnimeError } from "aniwatch";
 import type { ErrorHandler, NotFoundHandler } from "hono";
 import type { ContentfulStatusCode } from "hono/utils/http-status";
+import { logger } from "./logger.js";
 
 const errResp: { status: ContentfulStatusCode; message: string } = {
-  status: 500,
-  message: "Internal Server Error",
+    status: 500,
+    message: "Internal Server Error",
 };
 
 export const errorHandler: ErrorHandler = (err, c) => {
-  console.error(err);
+    logger.error(JSON.stringify(err));
 
-  if (err instanceof HiAnimeError) {
-    errResp.status = err.status as ContentfulStatusCode;
-    errResp.message = err.message;
-  }
+    if (err instanceof HiAnimeError) {
+        errResp.status = err.status as ContentfulStatusCode;
+        errResp.message = err.message;
+    }
 
-  return c.json(errResp, errResp.status);
+    return c.json(errResp, errResp.status);
 };
 
 export const notFoundHandler: NotFoundHandler = (c) => {
-  errResp.status = 404;
-  errResp.message = "Not Found";
+    errResp.status = 404;
+    errResp.message = "Not Found";
 
-  console.error(errResp);
-  return c.json(errResp, errResp.status);
+    logger.error(JSON.stringify(errResp));
+    return c.json(errResp, errResp.status);
 };
diff --git a/src/config/ratelimit.ts b/src/config/ratelimit.ts
index afd6e54..8bfc308 100644
--- a/src/config/ratelimit.ts
+++ b/src/config/ratelimit.ts
@@ -1,21 +1,22 @@
-import { config } from "dotenv";
 import { rateLimiter } from "hono-rate-limiter";
 import { getConnInfo } from "@hono/node-server/conninfo";
-
-config();
+import { env } from "./env.js";
 
 export const ratelimit = rateLimiter({
-  windowMs: Number(process.env.ANIWATCH_API_WINDOW_MS) || 30 * 60 * 1000,
-  limit: Number(process.env.ANIWATCH_API_MAX_REQS) || 6,
-  standardHeaders: "draft-7",
-  keyGenerator(c) {
-    const { remote } = getConnInfo(c);
-    const key =
-      `${String(remote.addressType)}_` +
-      `${String(remote.address)}:${String(remote.port)}`;
+    windowMs: env.ANIWATCH_API_WINDOW_MS,
+    limit: env.ANIWATCH_API_MAX_REQS,
+    standardHeaders: "draft-7",
+    keyGenerator(c) {
+        const { remote } = getConnInfo(c);
+        const key =
+            `${String(remote.addressType)}_` +
+            `${String(remote.address)}:${String(remote.port)}`;
 
-    return key;
-  },
-  handler: (c) =>
-    c.json({ status: 429, message: "Too Many Requests 😵" }, { status: 429 }),
+        return key;
+    },
+    handler: (c) =>
+        c.json(
+            { status: 429, message: "Too Many Requests 😵" },
+            { status: 429 }
+        ),
 });