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Khushi Singla
Khushi Singla

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🎤 Crack Interviews with AI: Building a Voice-Powered Mock Interview Simulator

Gemma 4 Challenge: Build With Gemma 4 Submission

What I Built

AI Voice Interview Simulator is an intelligent, voice-enabled mock interview platform that helps job seekers practice interviews with real-time feedback, emotion analysis, and performance tracking.

Most interview preparation platforms today are text-based and fail to simulate real conversational pressure or provide actionable feedback on communication skills.

This project solves that by creating a voice-based AI interview experience that:

  • conducts real-time mock interviews
  • asks adaptive questions based on responses
  • evaluates interview performance
  • analyzes emotional signals
  • tracks progress over time

The goal was to build a more realistic and interactive interview preparation platform rather than a static chatbot experience.


Features

🎤 Voice Interview Simulation

  • AI asks questions using text-to-speech
  • Users can answer using their microphone
  • Automatic speech transcription using Whisper

🧠 Dynamic AI Questioning

The interview flow adapts based on previous answers.

The platform supports:

  • General interviews
  • Technical interviews
  • HR interviews
  • Sales interviews

Difficulty levels:

  • Entry Level
  • Mid Level
  • Senior Level

The system also supports resume-based personalized interview generation.


📊 Real-Time Performance Scoring

After every response, the platform evaluates:

  • Clarity
  • Confidence
  • Relevance

Users receive instant AI-generated feedback after each answer.


🎭 Emotion Analysis

The system analyzes emotional signals from candidate responses and detects:

  • confidence
  • nervousness
  • enthusiasm
  • hesitation

This helps users understand both technical and communication performance.


📈 Interview History Dashboard

The platform stores previous interview sessions and allows users to:

  • review past interviews
  • track score improvements
  • analyze trends over time
  • revisit previous feedback

🔄 Resume Upload Support

Users can upload resumes in PDF format.

The AI then generates personalized interview questions based on:

  • skills
  • projects
  • experience
  • technologies mentioned in the resume

Demo

🌐 Live Applications

Prototype Version

https://ai-interview-simulator-prototype-bausbh9a9dsxk9e5uvws8w.streamlit.app/

Full Application

https://ai-interview-simulator-web.streamlit.app


📂 GitHub Repository

https://github.com/KhushiSingla-tech/ai-interview-simulator


🎥 Demo Video


Tech Stack

Component Technology
Frontend Streamlit
Workflow Automation n8n
LLM Groq (llama-3.1-8b-instant)
Voice Output Lemonfox TTS
Voice Input Lemonfox Whisper STT
Emotion Analysis Groq LLM
Database Supabase (PostgreSQL)
Backend Deployment Railway
Frontend Deployment Streamlit Cloud

Architecture

Workflow 1 — AI Interview

  • Receives user answer and conversation history
  • Sends context to AI workflow
  • Generates next interview question dynamically

Workflow 2 — Answer Scorer

  • Receives question and candidate answer
  • Scores clarity, confidence, and relevance
  • Returns structured feedback

How It Works

User Starts Interview
            ↓
AI Generates Question
            ↓
User Answers via Voice/Text
            ↓
Speech-to-Text Processing
            ↓
AI Evaluation + Emotion Analysis
            ↓
Feedback + Next Question
            ↓
Session Stored in Database
Enter fullscreen mode Exit fullscreen mode

Challenges Faced

Maintaining Conversational Flow

One challenge was preserving enough interview context so that follow-up questions felt natural and relevant.


Real-Time Voice Processing

Handling speech-to-text conversion while maintaining smooth interview flow required careful workflow orchestration.


Consistent Performance Evaluation

Interview scoring can be subjective, so tuning prompts for balanced evaluation across different answer styles required multiple iterations.


Future Improvements

Planned enhancements include:

  • real-time voice emotion detection
  • multilingual interview support
  • company-specific interview modes
  • coding round simulations
  • analytics dashboards
  • progress visualizations

Conclusion

Building AI Voice Interview Simulator demonstrated how conversational AI and voice workflows can improve interview preparation experiences.

The most exciting part of the project was creating adaptive interview interactions that respond dynamically to user answers while also providing structured performance feedback and emotion analysis.

The combination of voice interaction, AI evaluation, and adaptive questioning helped create a more realistic interview simulation platform.

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