AI-Based VoIP Call System Development
Budget: $750 – $1,500 USD
We are looking for an experienced backend / VoIP developer to build an AI-based call system with a fully integrated admin/management dashboard.
This project is not only about making AI calls, but about delivering a practical operational system that can control, bill, and immediately stop AI calls based on prepaid usage.
The AI call engine and the admin dashboard must be delivered as one integrated system.
Admin functionality is included in the core scope and is NOT a separate project.
Scope of Work (Included)
1. AI Call Core
- SIP-based outbound call handling (credentials provided)
- RTP audio capture
- G.711 μ-law / A-law
- Mono, 8kHz
- RTP → linear PCM conversion
- Real-time AI voice integration
Bi-directional audio flow is required:
- Call audio → AI (STT / processing)
- AI voice response (TTS) → back into the live call
- Basic AI-driven call flow(Call start → AI greeting → response loop → call end)
2. Stability & Session Handling
- Per-call session isolation
- Non-blocking audio streaming
- Timeout and error handling for AI API
- Graceful call termination on failure
- Stable handling of multiple concurrent calls (basic level)
3. Integrated Admin Dashboard (Required)
The admin dashboard is a mandatory part of this project and must be fully integrated with the call engine, not a standalone or mock interface.
Account Structure
- HQ / Distributor / Client roles
- Basic account creation, activation, and deactivation
Prepaid Billing & Control
- Prepaid balance per client
- Manual credit top-up (admin action)
- Real-time usage deduction handled automatically by the system
- Billing rate: KRW 13.72 per 10 seconds (KRW only)
- When balance reaches zero: Ongoing calls stop immediately, New calls are blocked
Monitoring
-Balance view
-Basic usage summary
-Call history (time, duration, deducted amount)
No payment gateway integration is required.
No USD conversion or exchange-rate logic is required.
Explicitly Out of Scope
- Postpaid billing
- Negative balances
- Payment gateway integration
- Advanced analytics or dashboards
- UI/UX polishing beyond functional level
- AI model training or fine-tuning
Definition of Done (Important)
The project is considered complete only when all conditions below are met:
- At least one real outbound call completes successfully with live bi-directional AI interaction
- Audio flows bi-directionally between the call and the AI
- The admin dashboard is fully integrated with the call engine
- Usage is deducted in real time by the system
- Calls stop immediately when the prepaid balance reaches zero
- All critical bugs are fixed and the system runs stably under normal usage
- Final verification and acceptance by the client
Contract & Payment Structure
- Base Payment: USD $1,200 (implementation)
- Success Bonus: USD $800 (Paid only after full completion, stabilization, and final acceptance)
- Total Possible Payment: USD $2,000
- Fixed-price, milestone-based contract
- No additional charges within the agreed scope
Ideal Candidate
- Strong experience with Asterisk / SIP / RTP
- Comfortable with real-time audio processing
- Experience integrating AI voice APIs (STT / TTS)
- Able to deliver end-to-end working systems, not partial demos
- Clear communication and responsibility for completion
When Applying, Please Include
- Your experience with SIP / RTP / VoIP systems
- Whether you work individually or as a team
- A brief description of a similar project you have completed
Please apply only if you are comfortable with the base + success bonus structure
and delivering the full scope described above.
This project is not only about making AI calls, but about delivering a practical operational system that can control, bill, and immediately stop AI calls based on prepaid usage.
The AI call engine and the admin dashboard must be delivered as one integrated system.
Admin functionality is included in the core scope and is NOT a separate project.
Scope of Work (Included)
1. AI Call Core
- SIP-based outbound call handling (credentials provided)
- RTP audio capture
- G.711 μ-law / A-law
- Mono, 8kHz
- RTP → linear PCM conversion
- Real-time AI voice integration
Bi-directional audio flow is required:
- Call audio → AI (STT / processing)
- AI voice response (TTS) → back into the live call
- Basic AI-driven call flow(Call start → AI greeting → response loop → call end)
2. Stability & Session Handling
- Per-call session isolation
- Non-blocking audio streaming
- Timeout and error handling for AI API
- Graceful call termination on failure
- Stable handling of multiple concurrent calls (basic level)
3. Integrated Admin Dashboard (Required)
The admin dashboard is a mandatory part of this project and must be fully integrated with the call engine, not a standalone or mock interface.
Account Structure
- HQ / Distributor / Client roles
- Basic account creation, activation, and deactivation
Prepaid Billing & Control
- Prepaid balance per client
- Manual credit top-up (admin action)
- Real-time usage deduction handled automatically by the system
- Billing rate: KRW 13.72 per 10 seconds (KRW only)
- When balance reaches zero: Ongoing calls stop immediately, New calls are blocked
Monitoring
-Balance view
-Basic usage summary
-Call history (time, duration, deducted amount)
No payment gateway integration is required.
No USD conversion or exchange-rate logic is required.
Explicitly Out of Scope
- Postpaid billing
- Negative balances
- Payment gateway integration
- Advanced analytics or dashboards
- UI/UX polishing beyond functional level
- AI model training or fine-tuning
Definition of Done (Important)
The project is considered complete only when all conditions below are met:
- At least one real outbound call completes successfully with live bi-directional AI interaction
- Audio flows bi-directionally between the call and the AI
- The admin dashboard is fully integrated with the call engine
- Usage is deducted in real time by the system
- Calls stop immediately when the prepaid balance reaches zero
- All critical bugs are fixed and the system runs stably under normal usage
- Final verification and acceptance by the client
Contract & Payment Structure
- Base Payment: USD $1,200 (implementation)
- Success Bonus: USD $800 (Paid only after full completion, stabilization, and final acceptance)
- Total Possible Payment: USD $2,000
- Fixed-price, milestone-based contract
- No additional charges within the agreed scope
Ideal Candidate
- Strong experience with Asterisk / SIP / RTP
- Comfortable with real-time audio processing
- Experience integrating AI voice APIs (STT / TTS)
- Able to deliver end-to-end working systems, not partial demos
- Clear communication and responsibility for completion
When Applying, Please Include
- Your experience with SIP / RTP / VoIP systems
- Whether you work individually or as a team
- A brief description of a similar project you have completed
Please apply only if you are comfortable with the base + success bonus structure
and delivering the full scope described above.