diff --git a/README.md b/README.md
index 5986175f..c75f125f 100644
--- a/README.md
+++ b/README.md
@@ -21,10 +21,18 @@ This is the repository for the TransitMatters Data Dashboard. Client code is wri
 
 1. Add `MBTA_V3_API_KEY` to your shell environment:
    - `export MBTA_V3_API_KEY='KEY'` in ~/.bashrc or ~/.zshrc
-2. Add your AWS credentials (AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY) to your shell environment, OR add them to a .boto config file with awscli command `aws configure`.
-3. In the root directory, run `npm install` to install all frontend and backend dependencies
-4. Run `npm start` to start both the JavaScript development server and the Python backend at the same time.
-5. Navigate to [http://localhost:3000](http://localhost:3000) (or the url provided after running `npm start`)
+2. In the root directory, run `npm install` to install all frontend and backend dependencies
+3. Run `npm start` to start both the JavaScript development server and the Python backend at the same time.
+4. Navigate to [http://localhost:3000](http://localhost:3000) (or the url provided after running `npm start`)
+
+### AWS Setup
+
+If you have access to AWS credentials, add them to your local setup for a better development experience
+
+1. Add your AWS credentials (AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY) to your shell environment, OR add them to a .boto config file with awscli command `aws configure`.
+2. Ensure that AWS is set to read from/to `us-east-1` via `export AWS_DEFAULT_REGION=us-east-1` or with an aws config
+
+AWS access is not required for development, but may be required for certain charts and data to appear
 
 ## Deployment Instructions
 
diff --git a/server/chalicelib/dynamo.py b/server/chalicelib/dynamo.py
index 6fb79b84..73b4703e 100644
--- a/server/chalicelib/dynamo.py
+++ b/server/chalicelib/dynamo.py
@@ -10,13 +10,13 @@
 dynamodb = boto3.resource("dynamodb")
 
 
-def query_daily_trips_on_route(table_name, route, start_date, end_date):
+def query_daily_trips_on_route(table_name: str, route, start_date: str | date, end_date: str | date):
     table = dynamodb.Table(table_name)
     response = table.query(KeyConditionExpression=Key("route").eq(route) & Key("date").between(start_date, end_date))
     return ddb_json.loads(response["Items"])
 
 
-def query_daily_trips_on_line(table_name, line, start_date, end_date):
+def query_daily_trips_on_line(table_name: str, line: str, start_date: str | date, end_date: str | date):
     route_keys = constants.LINE_TO_ROUTE_MAP[line]
     with concurrent.futures.ThreadPoolExecutor(max_workers=4) as executor:
         futures = [