Candidate Screener — Backend (Go)

Go HTTP server that accepts a candidate's resume PDF and a job description, runs them through an LLM on Amazon Bedrock, and returns a structured screening result for recruiters.

Stack

• Go — HTTP server (net/http)
• Amazon Bedrock — LLM inference (openai.gpt-oss-20b-1:0)
• MuPDF / go-fitz — PDF text extraction

Project Structure

backend-go/
├── main.go                 # Server setup, routes, CORS middleware
├── .env                    # Environment variables (not committed)
├── go.mod / go.sum
├── handlers/
│   └── application.go      # HTTP endpoints and response parsing
├── services/
│   ├── llm.go              # Amazon Bedrock client
│   └── pdf.go              # PDF text extractor
├── models/
│   └── models.go           # Request/response structs
└── uploads/                # Uploaded PDFs and saved analysis JSON

Setup

1. Prerequisites

• Go 1.22+
• MuPDF installed:

  brew install mupdf

• AWS account with Bedrock access and the model enabled

2. Environment Variables

Fill in .env:

AWS_ACCESS_KEY_ID=your_access_key
AWS_SECRET_ACCESS_KEY=your_secret_key
AWS_REGION=us-east-1
PORT=8080

3. Run

CGO_CFLAGS="-I/opt/homebrew/opt/mupdf/include" \
CGO_LDFLAGS="-L/opt/homebrew/opt/mupdf/lib -lmupdf -lmupdf-third" \
go run main.go

Server starts at http://localhost:8080.

Docker

Build

docker build -t backend-go ./backend-go

Rebuild with the same -t backend-go tag whenever you change source or the Dockerfile — Docker doesn't watch files for you. Old images from previous builds become "dangling" once the tag moves; clean them up with:

docker image prune -f

Run

docker run --rm -p 8080:8080 --env-file backend-go/.env backend-go

--rm removes the container automatically when it stops, which is convenient during dev. To run it detached with a fixed name so you can stop/replace it explicitly:

docker run -d --name backend-go -p 8080:8080 --env-file backend-go/.env backend-go

# to replace after a rebuild
docker stop backend-go && docker rm backend-go
docker run -d --name backend-go -p 8080:8080 --env-file backend-go/.env backend-go

API

GET /health

Returns server status.

curl http://localhost:8080/health
# {"status":"ok"}

---

POST /analyze

Upload a candidate's resume PDF and your job description. Returns a structured screening result.

Form fields:

Field	Type	Description
resume	file	Candidate resume in PDF format
job	text	Job description as plain text

curl -X POST http://localhost:8080/analyze \
  -F "resume=@uploads/candidate.pdf" \
  -F "job=We are looking for a Senior Go engineer with Kubernetes experience..."

Response:

{
  "strong_points": [
    "5 years of Go experience",
    "Kubernetes and Docker proficiency"
  ],
  "weak_points": [
    "No mention of CI/CD pipelines",
    "Limited cloud infrastructure exposure"
  ],
  "conclusion": "Yes",
  "match_percentage": "78%"
}

---

GET /analysis

Returns the most recently saved screening result.

curl http://localhost:8080/analysis

CORS

The server allows all origins (*) in development. Restrict Access-Control-Allow-Origin to your frontend domain before deploying to production.