At a glance

Role	R&D Engineer — sole developer
Company	ISTL (Integrated Software and Technologies Limited)
Timeline	During Jul 2020 – Feb 2023
Team	Solo
Users	250+ employees & field agents
Modules	Requisition · Procurement · Payments · Stock/Assets · Attendance
Stack	Django · Python · MySQL · Docker · LDAP / OAuth · Linux
Status	Deployed internally

Problem & context

ISTL needed to run its internal operations for 250+ employees and field agents — raising requests, routing them through layers of approval, ordering from vendors, paying them, tracking stock, and recording attendance. Done manually, it was slow and hard to audit. I built Assets Nexus, solo: a SaaS platform that centralizes the entire requisition → approval → procurement → distribution lifecycle, plus stock and attendance. Every device it ran on was secured by Data Citadel.

Modules

• Requisition & approvals — requests routed through the org command chain.
• Procurement & vendor management — purchase orders and vendor records.
• Vendor payments — payment tracking against purchase orders.
• Stock & asset management — inventory, distribution, and returns.
• Attendance — check-in/out for employees and field agents.
• Access & audit — role-based access via LDAP/OAuth identities, with an audit trail and reporting dashboards.

Architecture

A Django application backed by MySQL, containerized with Docker on Linux. Authentication uses LDAP for directory/login and OAuth for SSO, while an HRM integration supplies the employee and organizational hierarchy that drives the approval chain. Employees and field agents work across the modules through one role-based interface.

flowchart TB
    Emp[Employees] --> App
    Agents[Field Agents] --> App
    LDAP[LDAP Directory] --> App
    OAuth[OAuth SSO] --> App
    HRM[HRM System] -->|org hierarchy| App
    subgraph App[Assets Nexus · Django]
        Req[Requisition & Approvals]
        Proc[Procurement & Payments]
        Stock[Stock & Assets]
        Att[Attendance]
        RBAC[RBAC & Audit]
    end
    App --> DB[(MySQL)]
    Proc --> Vendor[Vendors]

Key flow

The requisition lifecycle — request through the command chain to distribution.

sequenceDiagram
    actor Employee
    participant App as Assets Nexus
    participant HRM as HRM (org hierarchy)
    participant Chain as Command Chain
    participant Vendor as Vendor
    participant Stock as Stock / Inventory

    Employee->>App: Raise requisition
    App->>HRM: Resolve approval chain
    loop Each level in the command chain
        App->>Chain: Request approval
        Chain-->>App: Approve / reject
    end
    App->>Vendor: Create purchase order
    Vendor-->>App: Fulfil order
    App->>App: Record vendor payment
    App->>Stock: Update inventory
    App-->>Employee: Asset distributed

Data model

Employees, requisitions, approvals, vendors, stock, and attendance.

erDiagram
    DEPARTMENT ||--o{ EMPLOYEE : has
    ROLE ||--o{ EMPLOYEE : grants
    EMPLOYEE ||--o{ REQUISITION : raises
    REQUISITION ||--o{ APPROVAL : "routed through"
    EMPLOYEE ||--o{ APPROVAL : approves
    REQUISITION ||--o{ PURCHASE_ORDER : generates
    VENDOR ||--o{ PURCHASE_ORDER : fulfils
    PURCHASE_ORDER ||--o| PAYMENT : "paid via"
    PURCHASE_ORDER ||--o{ ASSET : delivers
    ASSET }o--|| STOCK : "tracked in"
    EMPLOYEE ||--o{ ATTENDANCE : logs

What I built

• A Django SaaS platform unifying requisition, procurement, stock, and attendance for the whole organization.
• A multi-level approval workflow that routes each requisition dynamically through the organizational command chain sourced from HRM.
• Identity & access — LDAP directory/login, OAuth SSO, HRM employee data, and role-based access control with an audit trail.
• Order management and vendor payment tracking through purchase orders.
• Stock/inventory management with asset distribution and returns.
• An attendance module for employees and field agents.
• Dockerized deployment on Linux, with endpoints hardened by Data Citadel.

Challenges & trade-offs

• Dynamic approval chains — different departments have different hierarchies, so the engine resolves the right chain of approvers per requisition from the live org structure rather than hard-coded levels.
• Stock consistency — keeping inventory accurate across concurrent procurement, distribution, and returns.
• Field-agent attendance — recording attendance reliably for agents working away from the office.

Outcome

• Served 250+ employees and field agents across the organization.
• Boosted procurement efficiency ~20% and reduced asset costs ~15%.
• Replaced a slow, manual, hard-to-audit process with a single auditable platform spanning requisition, approval, procurement, payment, stock, and attendance.