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:
[email protected]
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: +41 23 3214 43
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
✍️ SignAI
Generate clean, professional email signatures using AI — all by sending an email.
Built with 💙 using Azure Functions, Azure OpenAI, C#, and Postmark.
📬 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
🚀 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
🛠 Tech Stack
| Component | Technology Used |
|---|---|
| 💌 Email Handling | Postmark Inbound |
| 🧠 AI Generation | Azure OpenAI Service |
| ⚙️ Backend API | Azure Functions |
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
Inbound Email Parsing
Postmark handles incoming emails and routes them to an Azure Function via webhook.Prompt Engineering
A carefully crafted system prompt ensures the model outputs minimal, inline-styled, accessible HTML using user preferences.Response Generation
Azure OpenAI generates the signature, which is emailed back using Postmark Outbound.No UI Needed
Everything is done via email — a playful constraint that led to a surprisingly intuitive UX.
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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