SignAI - AI-powered service email signatures

This is a submission for the Postmark Challenge: Inbox Innovators.

What I Built

SignAI is a minimal, AI-powered service that generates clean, professional email signatures — just by sending an email.

No forms. No UI. Just email.

Users can send their contact info and preferences to a dedicated Postmark Inbound address, and receive a responsive, GPT-generated HTML signature in return.

It’s a fun, developer-focused take on signature generation — great for personal branding or team-wide consistency.

Demo

📬 Try it yourself!
Send an email to:
[e-mail]

Example Email Body:

Name: Emanuele Bartolesi
Role: Senior Cloud Engineer at Xebia
Website: https://emanuelebartolesi.com
LinkedIn: /in/kasuken
GitHub: https://github.com/kasuken
Phone: [phone]
Pronouns: he/him
Style: Minimalist, monochrome

🔁 Within seconds, you’ll get a reply email with:

• ✨ A ready-to-copy HTML signature
• 🖼️ A rendered inline preview
• 📅 (Optional) a download link or vCard

Here’s a preview of a signature created by the bot:

Note: Use any dummy data — no backend validation is enforced during this challenge demo.

Code Repository

kasuken / SignAI

Generate clean, professional email signatures using AI — all by sending an email

✍️ SignAI

Generate clean, professional email signatures using AI — all by sending an email.

Built with 💙 using Azure Functions, Azure OpenAI, C#, and Postmark.

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📬 What Is It?

SignAI is an AI-powered service that creates minimalist, responsive HTML email signatures based on user input — all via email Send your contact info and preferences to a dedicated email address, and SignAI will reply with ready-to-use signatures.

This project is created for the dev.to challenge: https://dev.to/devteam/join-the-postmark-challenge-inbox-innovators-3000-in-prizes-497l?bb=232850

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🚀 Features

• ✉️ Email-based UX – no forms, just send an email
• 🧠 AI-generated HTML signatures – minimal, accessible, and stylish
• 🎨 Supports preferences – dark/light style, emojis, links, layout tweaks
• 💡 Multiple themes (soon) – choose minimalist, colorful, corporate, etc.
• 🖼️ Preview-ready – includes rendered image preview for quick testing

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🛠 Tech Stack

Component	Technology Used
💌 Email Handling	Postmark Inbound
🧠 AI Generation	Azure OpenAI Service
⚙️ Backend API	Azure Functions

…

View on GitHub

How I Built It

This project is powered by a modern cloud-native stack:

Function	Tech
Email handling	Postmark Inbound Webhooks
AI generation	Azure OpenAI (GPT-4)
Backend/API	Azure Functions in C#
Infrastructure	Azure App Service + Azure Storage
Dev tools	GitHub Copilot, VS Code, Visual Studio, JetBrains Rider

The Process

1. Inbound Email Parsing
   Postmark handles incoming emails and routes them to an Azure Function via webhook.

2. Prompt Engineering
   A carefully crafted system prompt ensures the model outputs minimal, inline-styled, accessible HTML using user preferences.

3. Response Generation
   Azure OpenAI generates the signature, which is emailed back using Postmark Outbound.

4. No UI Needed
   Everything is done via email — a playful constraint that led to a surprisingly intuitive UX.

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This was a solo project built for fun, fast prototyping, and Postmark exploration.
Feel free to clone, fork, or contribute ideas!

Thanks for checking out SignAI and the Postmark Challenge! 📬

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