What is RPA (Robotic Process Automation)?
RPA (Robotic Process Automation) is a technology that uses software robots to automate repetitive tasks that would otherwise be performed by a human. The robot "mimics" human actions — it clicks the mouse, fills in forms, copies data, opens applications.
The key distinction: RPA operates at the user interface level — meaning it "sees" exactly what the user sees on screen. It doesn't need access to databases or APIs; as long as the application has a graphical interface, RPA can work with it.
What is traditional automation (API integration)?
Traditional automation means connecting systems directly via API (Application Programming Interface), database connectors or messaging systems. Applications communicate "under the hood" at the code level, without a user interface.
When the HR system adds a new employee, the API automatically calls Active Directory, creates an account and assigns permissions — everything happens in the background in real time, with no human intervention.
RPA vs. Traditional Automation: Key Differences
| Criterion | RPA | Traditional Automation (API) |
|---|---|---|
| How it works | Mimics human actions on the UI | Direct system-to-system communication |
| Implementation | Fast (days to weeks) | More complex (weeks to months) |
| Requirements | GUI application sufficient | Requires API or DB access |
| Cost | Lower upfront investment | Higher upfront cost |
| Speed | Slower (simulates a human) | Very fast (real time) |
| Reliability | Sensitive to UI changes | Stable (API changes are rare) |
| Scalability | Limited (more robots needed) | High (millions of transactions) |
| Maintenance | Higher (UI updates) | Lower (stable interfaces) |
When to use RPA?
Ideal scenarios for RPA:
- Legacy systems without an API — older applications with no modern interface
- Fast pilot projects — you need automation "yesterday"
- Processes spanning multiple applications — the robot switches between windows, just like a human
- Document processing — invoices, contracts, forms (with OCR)
- Limited budget — lower upfront investment
- Simple repetitive tasks — downloading reports, sending emails
When to use traditional automation (API)?
Ideal scenarios for API integration:
- Systems with a modern API — applications offer REST, GraphQL or SOAP
- Real-time communication — data must be synchronised instantly
- High data volumes — thousands to millions of transactions per day
- Mission-critical processes — payments, HR, security — requiring 99.9% reliability
- Long-term solution — strategic investment in IT infrastructure
- Bidirectional communication — systems exchange data with each other
Hybrid approach: Combining RPA + API
In practice we often combine both approaches — modern systems are connected via API while legacy applications are handled by RPA robots. This hybrid model leverages the strengths of both technologies.
Example of hybrid automation:
- API integration: HR system → Active Directory (account created instantly)
- RPA robot: Writes data into the old ERP with no API
- API integration: Sends notification to Microsoft Teams
ROI: Return on investment
Both technologies deliver significant ROI, but differ in timing and long-term costs:
RPA
- ROI: 6–12 months
- Lower upfront costs
- Fast implementation (weeks)
- Higher maintenance costs
- Sensitivity to UI changes
API Integration
- ROI: 12–24 months
- Higher upfront investment
- Implementation: months
- Lower operational costs
- Stable long-term solution
Security and compliance
RPA and security
RPA robots use real user accounts, so permissions must be configured correctly and audit logs maintained. Robots must not hold higher privileges than they actually need.
API and security
API integration offers stronger security — encrypted communication (HTTPS/TLS), OAuth 2.0 authentication, JWT tokens, rate limiting. All our API integrations meet NIS2 compliance standards in effect since 2024.
Technologies and tools
RPA platforms:
- UiPath — most popular platform with AI capabilities
- Automation Anywhere — cloud-native RPA
- Blue Prism — enterprise solution
- Power Automate Desktop — Microsoft solution (lower cost)
API integration:
- .NET Core / ASP.NET — our primary stack for enterprise
- Azure Service Bus — messaging and orchestration
- REST API, GraphQL — modern communication protocols
- Azure Logic Apps — low-code integration
Decision tree: What should you choose?
Ask yourself these questions:
- YES → API integration (better long-term solution)
- NO → RPA (the only option)
- Thousands+ → API integration (faster, more stable)
- Tens to hundreds → RPA is acceptable
- Critical (payments, HR) → API integration (99.9% reliability)
- Non-critical (reports) → RPA is acceptable
- Limited → RPA (faster start)
- Strategic investment → API integration
Conclusion
RPA is excellent for quick wins, legacy systems and pilot projects. API integration is a long-term investment for mission-critical processes, high data volumes and stable solutions.
Often the best approach is a hybrid model — connect modern systems via API and handle legacy applications with RPA. At Optimaly we have hands-on experience with both approaches and can advise on what is the right fit for your specific situation.
Want to automate manual processes? Visit our process automation page or book a consultation.