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| CLIENT SwiftMile Logistics Pvt. Ltd. Jaipur, Rajasthan | PRODUCT PayRoll365 — HR & Payroll Platform Attendance integration, payroll engine, PF/ESI/TDS compliance, Razorpay payouts, employee self-service app | TIMELINE 10 Weeks On time, on budget |
SwiftMile Logistics Pvt. Ltd. is a last-mile logistics company based in Jaipur, operating 5 distribution depots across Rajasthan with a workforce of 380 employees spanning full-time delivery staff, depot supervisors, warehouse workers, and office personnel. The company was growing rapidly — headcount had doubled in 18 months — but its HR and payroll processes had not scaled with it.
Payroll was being calculated manually in Excel by a 3-person HR team every month, a process that took 4 full working days and still produced an average of 14 payslip errors per cycle. Statutory compliance — PF, ESI, and TDS filings — were handled by an external CA with a 3-week lag, creating the risk of late-filing penalties. Employees had no self-service access to payslips, leave balances, or attendance records, generating a constant stream of HR queries.
Key Brains Tech built PayRoll365 — a custom HR and payroll automation platform covering biometric attendance integration, an automated payroll calculation engine (handling all salary components, deductions, and statutory contributions), direct salary disbursement via Razorpay, statutory compliance report generation, and an employee self-service mobile app. Delivered in 10 weeks, PayRoll365 reduced monthly payroll processing from 4 days to 6 hours, eliminated payroll errors, and achieved same-month statutory filing compliance.
| Key Outcomes at a Glance |
| Payroll processing time: 4 days → 6 hours (87% reduction) |
| Payroll errors per cycle: 14 → 0 (three consecutive error-free months post-launch) |
| Statutory compliance: same-month PF/ESI/TDS filing achieved for the first time |
| Employee self-service app: 94% adoption, HR query volume down 68% |
| 10-week end-to-end delivery — within scope and budget |
02 Client & Context
About SwiftMile Logistics Pvt. Ltd.
SwiftMile Logistics was founded in 2019 as a last-mile delivery partner for e-commerce companies and FMCG distributors. By 2025, the company operated 5 depot locations (Jaipur Main, Mansarovar, Ajmer Road, Sikar Road, and Tonk Road), a fleet of 210 delivery vehicles, and a workforce of 380 employees with widely varying salary structures: delivery executives on CTC + incentive models, depot supervisors on fixed monthly salaries, warehouse staff on daily wage or monthly arrangements, and 45 office/management staff on structured pay bands.
The heterogeneous workforce created significant payroll complexity. Delivery executive pay varied month to month based on delivery counts and incentive slabs. Daily-wage staff had to be calculated from the biometric attendance system. Overtime for warehouse staff was manually calculated from supervisor-submitted paper sheets. The combination of these variables made Excel-based payroll not just slow but error-prone.
| Pain Points Before PayRoll365 |
| 4 working days per month spent on payroll calculation by a 3-person HR team |
| Average 14 payslip errors per cycle — employee complaints, manual corrections, morale impact |
| Statutory filings (PF/ESI/TDS) handled externally with a 3-week lag — late filing penalty risk |
| Biometric attendance system had no integration — HR manually copied attendance data into Excel |
| No employee self-service: every payslip, leave balance, or attendance query required an HR call or visit |
| No offer letter or onboarding workflow: new joiners documented on paper, filed in physical folders |
03 Technology Stack
PayRoll365 is built on a React.js frontend, Node.js backend, and MongoDB database. The payroll calculation engine and statutory compliance modules are the most complex components — they encode India’s PF, ESI, and TDS rules in software, eliminating manual computation and the risk of regulatory non-compliance. The employee mobile app is a React Native PWA for Android, covering the majority of SwiftMile’s non-desk workforce.
| Layer | Technology | Purpose |
| Admin Frontend | React.js 18 | HR admin dashboard — employee records, payroll runs, compliance, reports |
| Employee App | React Native (Android PWA) | Employee self-service — payslips, leave requests, attendance, tax documents |
| Backend API | Node.js 20 + Express | Payroll engine, attendance processing, compliance calculations, notifications |
| Database | MongoDB Atlas | Employee records, salary structures, attendance, payroll runs, documents |
| Biometric Integration | ZKTeco API + custom parser | Pull daily attendance from existing ZKTeco biometric devices at all 5 depots |
| Salary Disbursement | Razorpay Payouts API | Direct bank transfer to employee accounts on payroll approval — supports UPI and IMPS |
| Compliance Engine | Custom Node.js module | PF, ESI, TDS, and professional tax calculations with monthly report generation |
| Document Generation | PDFKit (Node.js) | Payslip PDFs, offer letters, Form 16, PF challans auto-generated |
| SMS | MSG91 | Payslip delivery alerts, leave approval notifications, salary credit alerts |
| Storage | AWS S3 | Payslip PDFs, employee documents, Form 16, compliance reports — secure per-employee access |
| Hosting | AWS EC2 + MongoDB Atlas | Reliable, auto-backed-up infrastructure with nightly payroll data snapshots |
04 Solution Architecture
Module 1: Biometric Attendance Integration
SwiftMile already had ZKTeco biometric devices installed at all 5 depot locations. Rather than replacing this hardware, PayRoll365 integrates with it directly:
- A Node.js attendance sync service runs every hour, pulling punch-in/punch-out records from all 5 ZKTeco devices via the ZKTeco API and storing them in MongoDB
- Late arrivals, early departures, and absences are automatically calculated against each employee’s shift schedule and flagged for supervisor review
- Overtime is auto-calculated per employee type: warehouse staff on the standard Factories Act overtime rate (2x for hours beyond 9 per day), delivery executives on a separate overtime slab negotiated in their offer letters
- Supervisors approve or adjust attendance records via the HR dashboard before payroll lock-down — a one-click approval flow that replaced the paper sheet submission process
Module 2: Payroll Calculation Engine
The payroll engine is the core of PayRoll365. It handles SwiftMile’s four distinct employee categories and their respective salary structures:
- Delivery executives: base CTC + attendance-linked variable component + delivery count incentive (tiered slabs per route) + fuel reimbursement
- Depot supervisors: fixed monthly gross, with standard deductions and PF/ESI
- Warehouse staff (monthly): fixed basic + HRA + conveyance, with daily-wage workers calculated from actual attendance days
- Office/management staff: structured pay bands with flexi-benefit components, LTA, and medical allowance
On the 25th of each month, the HR manager triggers a payroll run from the dashboard. The engine pulls attendance data, calculates gross pay for all 380 employees, applies all deductions (PF employee contribution, ESI, professional tax, TDS, loan EMI deductions where applicable), and produces a payroll register for review. The entire calculation completes in under 4 minutes.
Module 3: Statutory Compliance Engine
The compliance module is what finally brought SwiftMile’s statutory filings in-house and on time:
- PF (Provident Fund): the engine calculates employer and employee PF contributions per employee each month, generates the ECR (Electronic Challan cum Return) file in the EPFO-specified format, and produces the challan for payment
- ESI (Employee State Insurance): contributions calculated for all eligible employees (gross salary below ₹21,000), with the monthly contribution challan and ESI return files auto-generated
- TDS: monthly TDS deductions calculated per employee based on projected annual income, applicable exemptions (HRA, 80C declarations), and current income tax slabs. Form 24Q generated quarterly.
- Professional Tax: state-specific PT slabs for Rajasthan applied automatically. PT challan generated monthly.
All compliance documents are generated on payroll run date and available for download from the HR dashboard. The HR team’s role in compliance reduced from 3 days of manual calculation and formatting to a 20-minute download and upload to the relevant government portals.
Module 4: Salary Disbursement via Razorpay Payouts
- On HR approval of the payroll run, PayRoll365 initiates salary transfers via Razorpay Payouts API to all 380 employee bank accounts simultaneously
- Each employee receives an SMS alert on salary credit with the net amount
- Failed transfers (incorrect account numbers, inactive accounts) are flagged to HR within 2 hours for manual correction — previously these failures were only discovered when employees complained
- Payroll disbursement that previously took 2 additional days (manual bank NEFT upload) now completes within 4 hours of approval
Module 5: Employee Self-Service Mobile App
The employee app is a React Native Android PWA, installable from a QR code — no app store required, critical for SwiftMile’s delivery executives who use entry-level Android devices.
- Payslip access: all payslips from the current year downloadable as PDF with one tap, delivered to WhatsApp on request
- Attendance view: employees can see their monthly attendance record, flagged late arrivals, and overtime count
- Leave management: apply for leave (casual, earned, sick), view approved/rejected status, check remaining leave balance
- Tax documents: Form 16 available for download in the app each year, eliminating the annual distribution exercise
- Investment declaration: employees submit Section 80C and HRA declarations digitally in the app for TDS calculation — replacing the paper form collection exercise
Module 6: HR Admin & Employee Lifecycle
- Digital onboarding: offer letter generated from a template, digitally signed, and stored in S3. Employee document upload (Aadhaar, PAN, bank details) done via the app on day one
- Employee master: complete employee records — personal details, bank account, salary structure, PF/ESI numbers, document repository
- Increment management: salary revision workflow — HR proposes a new CTC, manager approves, the new structure goes live from the selected effective date automatically
- Full and Final settlement: on employee exit, the F&F calculator handles outstanding salary, leave encashment, gratuity eligibility, and pending loan deductions
05 Project Delivery Timeline
| Phase 1 Weeks 1–2 | Discovery, Salary Structure Audit & Architecture Deep dive into all 4 employee category salary structures. PF/ESI/TDS compliance requirements documented. ZKTeco API tested at one depot. MongoDB schema and system architecture signed off by SwiftMile HR and IT leads. |
| Phase 2 Weeks 3–6 | Backend Payroll Engine, Compliance Module & Biometric Integration Node.js payroll calculation engine built and unit-tested against 6 months of historical payroll data. PF, ESI, TDS, and PT compliance modules built. ZKTeco attendance sync deployed across all 5 depots and verified. Razorpay Payouts API integrated. |
| Phase 3 Weeks 7–9 | HR Dashboard, Employee App & Document Generation React.js HR admin dashboard built. React Native employee PWA built and tested. PDFKit payslip and compliance document generation built. SMS alerts configured. All modules integrated end-to-end on staging. |
| Phase 4 Week 10 | Data Migration, UAT, Training & Go-Live 380 employee records migrated from Excel. 6 months of historical payslip data imported. HR team training (1 day). Employee app onboarding (QR code rollout via WhatsApp to all staff). First live payroll run processed and disbursed successfully in week 10. |
06 Results & Business Impact
SwiftMile’s HR director conducted a formal review at 30, 60, and 90 days post-launch. The following figures are drawn from SwiftMile’s own HR records and payroll run logs within PayRoll365.
| 87% Faster payroll processing | 0 Payroll errors (3 months) | 68% Fewer HR queries | 94% Employee app adoption |
Detailed Impact Breakdown
Payroll Processing
- Monthly payroll processing time fell from 4 working days to 6 hours — an 87% reduction. The HR team now completes payroll processing on the 25th of each month and releases payslips by the 26th, compared to payslips being distributed on the 5th–7th of the following month previously.
- Three consecutive payroll cycles post-launch were completed with zero payslip errors, compared to an average of 14 errors per cycle previously. The primary error sources (manual overtime miscalculation and incentive slab misapplication) were eliminated by the automated engine.
Statutory Compliance
- PF and ESI challans are now filed on the 15th of each month — well within the statutory deadline — compared to the previous pattern of filing via the external CA between the 18th and 25th. SwiftMile has not incurred a late filing penalty since go-live.
- The annual Form 16 exercise — previously a 3-day manual task involving the external CA — was completed entirely within PayRoll365 in under 2 hours. All 380 Form 16s were generated, verified, and made available in the employee app.
Employee Experience & HR Efficiency
- Employee self-service app adoption reached 94% within 30 days of launch. The most-used features were payslip download (used by 91% of employees within the first week) and leave balance check.
- HR query volume related to payslips, leave balances, and attendance records fell by 68%. The HR team redirected this time to onboarding quality and performance management.
| Cost Impact Summary |
| External CA payroll + compliance fees: estimated ₹3.6 lakh/year savings (partially brought in-house) |
| Late filing penalty risk eliminated: prior year late filing penalties totalled ₹1.1 lakh |
| HR overtime eliminated: 3 HR staff working 4 extra days/month on payroll = 144 person-days/year recovered |
| Employee morale: exit interviews post-launch cited payslip accuracy and timely salary as positive improvements |
07 Client Testimonial
| “Payroll used to be a nightmare every month. My HR team dreaded the last week of the month. We would make mistakes, employees would complain, and we were always filing PF late. Now we run payroll in a morning, salaries are in accounts by the afternoon, and my team has time to actually do HR work instead of just number-crunching. The delivery boys love being able to check their payslip on their phone without having to come to the depot office.” Neha Choudhary HR Director, SwiftMile Logistics Pvt. Ltd. |
08 Challenges & How We Solved Them
Challenge 1: Heterogeneous Salary Structure Complexity
SwiftMile’s four employee categories had fundamentally different salary structures, and the incentive slab logic for delivery executives had 11 separate tiers based on monthly delivery count thresholds. Encoding this correctly took significant discovery effort and multiple validation rounds.
- Solution: We ran three structured workshops with the HR director and two senior executives to document every salary component and rule in writing before writing a single line of payroll engine code. We then built a salary simulation tool (a simple UI in the admin dashboard) that allowed the HR team to test the engine against known historical payroll outputs for 20 sample employees before going live. Discrepancies were traced and resolved before the first live run.
Challenge 2: ZKTeco Device Connectivity at Remote Depots
Two of SwiftMile’s depots (Sikar Road and Tonk Road) had intermittent internet connectivity, causing the biometric sync service to fail periodically during testing.
- Solution: We built an offline-resilient sync layer: the attendance sync service uses a local queue on the depot device, storing punch records locally when the connection is down and batch-uploading when connectivity resumes. The HR dashboard shows a sync health indicator per depot so the team can proactively identify and resolve connectivity issues before payroll lock-down.
Challenge 3: Employee Bank Account Data Quality
When migrating 380 employee records from Excel, we found that 47 employees had incomplete or incorrect bank account details (wrong IFSC codes, outdated account numbers), which would have caused salary disbursement failures.
- Solution: We built a bank account validation step into the employee onboarding flow (penny drop verification via Razorpay’s account validation API). For the 47 existing records with issues, we ran a WhatsApp campaign asking employees to update their details via the app before the first live payroll run, resolving 43 of the 47 before go-live.
09 Future Roadmap
- Performance management module: A quarterly goal-setting and appraisal workflow tied to increment management, allowing managers to document performance ratings digitally and link them directly to the salary revision workflow in PayRoll365.
- GPS attendance for field staff: For delivery executives who rarely visit the depot, a GPS-based check-in feature in the mobile app to replace biometric attendance — marking shift start and end from their delivery route.
- Loan & advance management: A digital employee loan and salary advance module, tracking disbursement, EMI deduction schedule, and outstanding balance — replacing the current manual Excel tracker.
- Multi-company support: SwiftMile’s promoters are considering spinning out a separate entity for their new warehousing business. A multi-company PayRoll365 configuration is on the roadmap to manage both entities from a single platform.
10 About Key Brains Tech
Key Brains Tech Pvt. Ltd. is a Jaipur-based software development company specialising in custom web applications, mobile apps, AI/ML integration, and enterprise software solutions. Founded in 2021, we serve clients across healthcare, retail, education, real estate, and fintech sectors across India and internationally.
| Service Area | Technologies |
| Full-Stack Web Development | React.js, Node.js, Next.js, PHP (Laravel), MongoDB, PostgreSQL, MySQL |
| Mobile Applications | React Native, Android (Kotlin), iOS (Swift), PWA |
| AI & Machine Learning | Python, scikit-learn, TensorFlow, OpenAI API, FastAPI |
| Cloud & DevOps | AWS, GCP, Docker, GitHub Actions, CI/CD pipelines |
| Integrations & APIs | Razorpay, Twilio, WhatsApp Business API, Salesforce, SAP, Zoho |
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