My Role
Full-stack and workflow engineer
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Interactive full-stack buildFlagship case study
Employee Scheduling & Team Management System
Teams need to balance availability, coverage, shift changes, and permissions without relying on disconnected spreadsheets and messages.
Interactive preview
Full demoWhat I Built
Comprehensive scheduling platform with real-time updates, shift swapping, and role-based access. Flask + React web app paired with React Native + Firebase mobile app, boosting team coordination by 30%.
Evidence
Working interface, documented system behavior, and implementation-level decisions.
Technical Architecture
From system input to explainable output.
The control gate is shown as a first-class stage, not an afterthought added around the workflow.
Technical Decisions
- Built a Flask REST API and React web client backed by a shared scheduling model, so the same shift data drives both the manager view and the employee view without duplicate logic.
- Implemented role-based access so managers publish and approve while employees only see and act on their own shifts, checked on the server rather than hidden in the UI.
- Designed a shift-swap workflow with request, counter-party acceptance, and manager approval states, preventing the double-booking that manual swaps caused.
Security Considerations
- Implemented role-based access so managers publish and approve while employees only see and act on their own shifts, checked on the server rather than hidden in the UI.
Outcome & Evidence
- Added real-time propagation over Firebase listeners so a published change reaches every device without a refresh.
- Reduced schedule coordination overhead by roughly 30% measured against the manual process it replaced.
FlaskReactReact NativeFirebaseFull Stack
Working product
Try the interactive demo.
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employee-scheduling-team.zainkhalilkhan.com
Scheduling
Workforce coverage control
SchedulingWorkspace2 updates
ShiftOpsWORKFORCE CONTROL
WEEK 42 · CHICAGO OPERATIONS
Coverage without guesswork.
Manager view: click any cell to open the roster and assign or unassign staff. Understaffed shifts flash red; approve claimed swaps and the grid updates live.
Shifts
21
Fully staffed
14
Understaffed
7
| Shift | Mon | Tue | Wed | Thu | Fri | Sat | Sun |
|---|---|---|---|---|---|---|---|
Morning needs 3 · 6h | |||||||
Afternoon needs 3 · 6h | |||||||
Night needs 2 · 8h |
ManagerServerCookgreen = staffedred = understaffed
Shift Swap Requests2 pending
Jordan gives up Wed Morning to Maya
Doctor appointment Wed morning
Sam gives up Fri Night
Class conflict Friday night
Scheduled hoursovertime past 40h
Alex
40h
Devon
40h
Jordan
42h · OT
Priya
42h · OT
Maya
46h · OT
Sam
66h · OT
Chris
42h · OT
Zain Khalil Khan
Client-side sandbox. State is in memory and nothing is sent to a server.
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