Django deployment on railway hosting error: gunicorn command not found

Am attempting to deploy my django project on railway hosting but It crashes during deployment and outputs the error below

gunicorn command not found

Below are the deployment logs

Applying auth.0004_alter_user_username_opts... OK
Applying auth.0005_alter_user_last_login_null... OK
Applying auth.0006_require_contenttypes_0002... OK
Applying auth.0007_alter_validators_add_error_messages... OK
Applying auth.0008_alter_user_username_max_length... OK
Applying auth.0009_alter_user_last_name_max_length... OK
Applying auth.0010_alter_group_name_max_length... OK
Applying auth.0011_update_proxy_permissions... OK
Applying auth.0012_alter_user_first_name_max_length... OK
Applying sessions.0001_initial... OK
Applying sites.0001_initial... OK
Applying sites.0002_alter_domain_unique... OK
/bin/bash: line 1: gunicorn: command not found