diff --git a/README.md b/README.md
index ded9be1..3413738 100644
--- a/README.md
+++ b/README.md
@@ -1,14 +1,50 @@
 # themepark-assistant
 A tool for improving your trips to themeparks - once developed
 
-## Testing
-Send request
+## Repo structure
+- /api: API implementation
+    - ./: config files
+    - /src: API Code
+        - /db: Database client, schema & migrations
+        - /errors: Error types
+            - index.ts: Exporter for all error classes
+        - /jobs: Background tasks
+        - /lib: Reusable functions
+        - /routes: API Endpoints
+        - /types: Data type definitions
+        - index.ts: Entrypoint for API Requests & background tasks on Cloudflare Workers
 
+
+## Development
+### Run enviromnment
+Run worker locally (without remote d1 access, scheduled tasks not available)
+```bash
+npx wrangler dev
+```
+
+Run worker locally (without remote d1 access, scheduled tasks available)
+```bash
+npx wrangler dev --test-scheduled
+```
+
+Run worker locally (with remote connection to d1, scheduled tasks available)
+```bash
+npx wrangler dev --remote --test-scheduled
+```
+
+### Requests
+Send request with bearer authentication
 ```bash
 curl -H "Authorization: Bearer insecure-token" http://127.0.0.1:8787/notification/list
 ```
 
-## Update cloudflare d1 db
+Run request with cron expression (for executing background tasks)
+```bash
+curl "http://localhost:8787/__scheduled?cron=*+*+*+*+*"
+```
+
+### Drizzle DB migrations
+Update cloudflare d1 db
 DB scheme is defined in typescript
 
 apply changes
@@ -21,35 +57,25 @@ export sql statements instead of running migration
 npx drizzle-kit export --config=drizzle-dev.config.ts
 ```
 
-## SQLite / D1
+### Useful sql statements for SQLite / D1
 Delete view
 ```sql
 DROP VIEW IF EXISTS attraction_subscriptions;
 ```
 
-## Cloudflare workers tricks
+### Cloudflare workers tricks
 If types are missing, run:
 ```bash
 npx wrangler types
 ```
 
-## Testing cronjobs
-Run worker locally (without remote d1 access)
-```bash
-npx wrangler dev --test-scheduled
-```
-
-Run worker locally (with remote connection to d1)
-```bash
-npx wrangler dev --remote --test-scheduled
-```
-
-Run curl request with cron expression
-```bash
-curl "http://localhost:8787/__scheduled?cron=*+*+*+*+*"
-```
-
-## Authentication endpoints
+## Authentication endpoints (auth.js)
 - /auth/signin -> Login
 - /auth/signout -> Logout
-- /auth/callback/github -> Callback for GitHub OAuth config
\ No newline at end of file
+- /auth/callback/github -> Callback for GitHub OAuth config
+
+## Contributing
+TBD
+
+## License
+TBD
\ No newline at end of file
diff --git a/api/src/errors/background-error.ts b/api/src/errors/background-error.ts
index 338a5ad..d05207f 100644
--- a/api/src/errors/background-error.ts
+++ b/api/src/errors/background-error.ts
@@ -1,15 +1,8 @@
 // Error classes for background jobs
+import { BaseError } from "./base-error";
 
 // Class for custom background errors
-export class BackgroundJobError extends Error{
-    cause?: unknown;
-
-    constructor(message: string, cause?: unknown){
-        super(message);
-        this.name = this.constructor.name;
-        this.cause = cause;
-    }
-}
+export class BackgroundJobError extends BaseError{}
 
 // Errors based on class BackgroundJobError
 export class BackgroundDatabaseError extends BackgroundJobError{
@@ -18,12 +11,6 @@ export class BackgroundDatabaseError extends BackgroundJobError{
     }
 }
 
-export class BackgroundFetchError extends BackgroundJobError{
-    constructor(cause?: unknown){
-        super('Fetching data failed', cause);
-    }
-}
-
 export class AttractionImportError extends BackgroundJobError{
     constructor(cause?: unknown){
         super('Failed to import attractions into database.', cause);
diff --git a/api/src/errors/base-error.ts b/api/src/errors/base-error.ts
new file mode 100644
index 0000000..3e17ce4
--- /dev/null
+++ b/api/src/errors/base-error.ts
@@ -0,0 +1,10 @@
+// Base for new error domains/classes
+export class BaseError extends Error{
+    cause?: unknown;
+
+    constructor(message: string, cause?: unknown){
+        super(message);
+        this.name = this.constructor.name;
+        this.cause = cause;
+    }
+}
\ No newline at end of file
diff --git a/api/src/errors/index.ts b/api/src/errors/index.ts
new file mode 100644
index 0000000..4eaca3f
--- /dev/null
+++ b/api/src/errors/index.ts
@@ -0,0 +1,3 @@
+export * from './background-error'
+export * from './http-error'
+export * from './lib-error'
\ No newline at end of file
diff --git a/api/src/errors/lib-error.ts b/api/src/errors/lib-error.ts
new file mode 100644
index 0000000..2cad4da
--- /dev/null
+++ b/api/src/errors/lib-error.ts
@@ -0,0 +1,26 @@
+// Errors in custom libs
+import { BaseError } from "./base-error";
+
+export class LibError extends BaseError{}
+
+export class FetchError extends LibError{
+    constructor(cause?: unknown, source?: string){
+        super(
+            source
+            ? `Fetching data from ${source} failed`
+            : 'Fetching data failed',
+            cause);
+    }
+}
+
+export class BatchExecutionError extends LibError{
+    constructor(cause?: unknown){
+        super('Batched execution failed.', cause);
+    }
+}
+
+export class HTTPError extends LibError{
+    constructor(errorCode: number, cause?: unknown){
+        super(`Received HTTP error code: ${errorCode}`, cause);
+    }
+}
\ No newline at end of file
diff --git a/api/src/jobs/send-notifications.ts b/api/src/jobs/send-notifications.ts
index af7c610..11fa89a 100644
--- a/api/src/jobs/send-notifications.ts
+++ b/api/src/jobs/send-notifications.ts
@@ -3,7 +3,7 @@ import { getDbEnv } from '../db/client'
 import { subscribedThemeparks, attractionSubscriptions } from "../db/schema";
 import { SubscribedThemeparks } from "../types/subscribed-themeparks";
 import { AttractionSubscription } from "../types/attraction-subscriptions";
-import { KVParseError, SendNotificationError } from "../errors/background-error";
+import { KVParseError, SendNotificationError } from "../errors";
 import httpRequest from "../lib/http-request";
 import fetchAttractions from "../lib/fetch-attractions";
 
diff --git a/api/src/jobs/update-attraction-list.ts b/api/src/jobs/update-attraction-list.ts
index eddfeba..0fed46b 100644
--- a/api/src/jobs/update-attraction-list.ts
+++ b/api/src/jobs/update-attraction-list.ts
@@ -3,7 +3,7 @@ import { attraction, themepark } from '../db/schema'
 import { inArray } from 'drizzle-orm'
 import { Attraction } from '../types/attraction'
 import { ThemeparkSelect } from '../types/themepark'
-import { AttractionImportError, BackgroundDatabaseError } from '../errors/background-error'
+import { AttractionImportError, BackgroundDatabaseError } from '../errors'
 import asyncBatchJob from '../lib/async-batch-job'
 import fetchAttractions from '../lib/fetch-attractions'
 
diff --git a/api/src/jobs/update-themepark-data.ts b/api/src/jobs/update-themepark-data.ts
index daec8de..44d8ca9 100644
--- a/api/src/jobs/update-themepark-data.ts
+++ b/api/src/jobs/update-themepark-data.ts
@@ -1,7 +1,7 @@
 import { getDbEnv } from '../db/client'
 import { themepark } from '../db/schema'
 import { countryCodesDE } from '../lib/countries'
-import { BackgroundFetchError, ThemeparkUpdateError } from '../errors/background-error'
+import { FetchError, ThemeparkUpdateError } from '../errors'
 import httpRequest from '../lib/http-request'
 import asyncBatchJob from '../lib/async-batch-job'
 
@@ -31,7 +31,7 @@ async function fetchThemeparks(
         return result;
     }
     catch(e){
-        throw new BackgroundFetchError(e);
+        throw new FetchError(e);
     }
 }
 
diff --git a/api/src/lib/async-batch-job.ts b/api/src/lib/async-batch-job.ts
index f41818c..a9e84ca 100644
--- a/api/src/lib/async-batch-job.ts
+++ b/api/src/lib/async-batch-job.ts
@@ -1,3 +1,5 @@
+import { BatchExecutionError } from "../errors";
+
 /**
  * Run any async operation in (multiple) batches
  * @param data Array to split into batches
@@ -12,6 +14,6 @@ export default async function asyncBatchJob<T>(data: T[], batchSize: number = 20
         }
     }
     catch(e){
-        throw new Error(`Batch execution failed: ${e}`);
+        throw new BatchExecutionError(e);
     }
 }
\ No newline at end of file
diff --git a/api/src/lib/fetch-attractions.ts b/api/src/lib/fetch-attractions.ts
index c83e7e1..53a3950 100644
--- a/api/src/lib/fetch-attractions.ts
+++ b/api/src/lib/fetch-attractions.ts
@@ -1,5 +1,6 @@
 import { AttractionImport } from '../types/attraction'
 import httpRequest from '../lib/http-request'
+import { FetchError } from '../errors';
 
 /**
  * Fetching the attractions from a specified park
@@ -25,6 +26,6 @@ export default async function fetchAttractions(
         return result;
     }
     catch(e){
-        throw new Error(`Failed to fetch attractions: ${e}`);
+        throw new FetchError(e, endpoint);
     }
 }
\ No newline at end of file
diff --git a/api/src/lib/http-request.ts b/api/src/lib/http-request.ts
index 47267e2..fdc0aea 100644
--- a/api/src/lib/http-request.ts
+++ b/api/src/lib/http-request.ts
@@ -1,3 +1,5 @@
+import { HTTPError } from "../errors";
+
 /**
  * Executes a HTTP Request with option for custom header & body parameters
  * @param endpoint Request endpoint
@@ -26,7 +28,7 @@ export default async function httpRequest<TResponse, TBody = undefined>(
 
 
     if (!response.ok){
-        throw new Error(`HTTP error! Status: ${response.status}`);
+        throw new HTTPError(response.status);
     }
 
     if(response.status === 204){
diff --git a/api/src/lib/user-auth.ts b/api/src/lib/user-auth.ts
index f71b586..550be54 100644
--- a/api/src/lib/user-auth.ts
+++ b/api/src/lib/user-auth.ts
@@ -4,7 +4,7 @@ import { UserSelect } from "../types/user";
 import { user } from "../db/schema";
 import { like } from "drizzle-orm";
 import { DrizzleD1Database } from "drizzle-orm/d1";
-import { MissingMailError, UserInactiveError, DatabaseError } from "../errors/http-error";
+import { MissingMailError, UserInactiveError, DatabaseError } from "../errors";
 
 /**
  * Returns the details of a user from the given context
diff --git a/api/src/routes/attraction.ts b/api/src/routes/attraction.ts
index 291d429..bf59d49 100644
--- a/api/src/routes/attraction.ts
+++ b/api/src/routes/attraction.ts
@@ -2,7 +2,7 @@ import { Hono, Context } from 'hono'
 import { getDbContext } from '../db/client'
 import { attractionNotification, notificationMethod } from '../db/schema'
 import { and, eq } from 'drizzle-orm'
-import { DatabaseError, InvalidParameter, MissingParameter } from '../errors/http-error'
+import { DatabaseError, InvalidParameter, MissingParameter } from '../errors'
 import { getUser } from '../lib/user-auth'
 import { Message } from '../types/response'
 import { NotificationMethodSelect } from '../types/notification-method'
diff --git a/api/src/routes/themepark.ts b/api/src/routes/themepark.ts
index c1b4d03..7bd89b9 100644
--- a/api/src/routes/themepark.ts
+++ b/api/src/routes/themepark.ts
@@ -3,7 +3,7 @@ import { getDbContext } from '../db/client'
 import { themepark, attraction } from '../db/schema'
 import { responseCache } from '../lib/cache'
 import { eq } from 'drizzle-orm'
-import { DatabaseError } from '../errors/http-error'
+import { DatabaseError } from '../errors'
 
 const app = new Hono()