Piler is an open-source enterprise email archiving application. It captures email from a wide range of sources — mail servers, Exchange, M365, and standard SMTP — and stores a searchable, tamper-proof copy of every message for compliance, legal discovery, and long-term record keeping. Using a high-performance full-text index, it makes archived mail fast to search even at very large volumes.

Key Features

• Universal email capture — Ingests mail from SMTP servers, Exchange, Microsoft 365, and journaling sources into a single archive.
• Full-text search — High-speed, index-backed search across the entire message store for instant retrieval.
• Tamper-evident storage — Stores messages in a form that helps detect unauthorised modifications after capture.
• Web-based access — Provides a web interface for authorised users to search, view, and export archived mail.
• Regulatory friendly — Built for compliance scenarios (FINRA, GDPR, corporate legal holds) with policy retention options.
• Scalable architecture — Handles millions of messages across a distributed, indexed backend.

Why Use Piler?

Whether driven by a regulatory requirement or the simple need to keep a dependable record of corporate communications, Piler gives organisations a self-hosted alternative to paid archiving appliances. It keeps your data on your own infrastructure, under your own control, with powerful search on top.

Use Cases

• Meeting email compliance and legal-hold obligations
• Retaining corporate communication records for audits and disputes
• Providing journalists, public bodies, and teams a searchable mail archive

Platform

Linux · Docker

Licence

GNU General Public License v3.0 (GPL-3.0)

Website

http://www.mailpiler.org