Request submission
Create a request with leave type, start and end dates, and a reason.
05HR WORKFLOW AUTOMATION
Leave Management System.
An employee leave application connecting request submission, personal history, and administrative decisions.
01 / OVERVIEW
Less friction in the approval flow.
LeaveFlow is a separated React frontend and Express backend. Employees submit requests and review their own history, while administrative endpoints provide an overview and status decisions.
My contribution
Frontend, API & database development, bringing the interface, business workflow, and data layer together.
02 / THE BUSINESS REQUIREMENT
The problem to solve.
A leave request needs to move from employee submission to an administrative decision with clear ownership. Employees should see their own requests, and completed decisions should be handled deliberately.
03 / THE APPLICATION
What the system does.
Personal request history
Retrieve requests for the authenticated user, ordered by creation date.
Administrative review
Review employee requests and decide between pending, approved, and rejected states.
Authenticated API
Bearer token verification and dedicated administrative middleware protect request routes.
04 / TECHNICAL ARCHITECTURE
How the layers connect.
01
Presentation
React · Vite · Tailwind CSS
Employee and administrative interfaces in a separate frontend application.
02
Application
Express.js · JWT
Authentication middleware and controllers for request creation, history, and status decisions.
03
Persistence
PostgreSQL · node-postgres
Parameterized SQL queries for users and leave requests.
05 / ENGINEERING DECISIONS
Deliberate choices.
Separate the interface from the API
Independent frontend and backend repositories keep presentation and application logic distinct.
Scope history to the authenticated user
The personal-history query uses the user identity supplied by authentication middleware, instead of accepting an arbitrary user identifier.
Use parameterized queries
The controller passes query values separately from SQL text for request creation, lookup, and updates.
06 / THE TECHNICAL CHALLENGE
Making an approval decision explicit.
Unrestricted status changes can make the request lifecycle ambiguous.
THE APPROACH
The status controller accepts a defined set of statuses, checks whether the request exists, and rejects changes to requests that have already been approved or rejected. Concurrent-update behavior remains a consideration for further hardening.
07 / THE RESULT
A connected application.
Employees can submit requests and review their own history. Administrative review uses a defined set of statuses, with checks for missing requests and decisions that have already been finalized.
Public sign-in interface. An authorized account is required to access employee and administrative workflows.
About this case study’s sources
React/Express/PostgreSQL dependencies and request behavior checked against both LeaveFlow repositories. Screenshot from the original portfolio; it may show an earlier interface.