Open OSCAR Server revives classic AIM and ICQ chat clients

Open OSCAR Server is an open-source instant-messaging server, written in Go, that acts as a compatible backend for classic AIM and ICQ clients. The project's GitHub README includes a screenshot of the Pidgin IM client connected to it, showing that the server also works with third-party clients built for the TOC protocol, not only the original AIM and ICQ software.

On the AIM side, the README lists support for Windows AIM clients versioned v1.x-v5.x and v6.x-v7.x, plus TOC1-protocol clients (Quick Buddy, gaim, TiK) and TOC2-protocol clients (vAIM, Miranda around v0.4.0.3, and iEM 1.0.1). On the ICQ side, it lists support for Windows ICQ clients numbered 98x, 99x, 2000x, 2001x, 2002x, 2003x, 4, and 5.

Feature coverage spans away messages, buddy icons (on AIM versions 4.x and 5.x), buddy lists, public and private chat rooms and exchanges, instant messaging, user profiles, privacy controls that allow or block specific users, a "Warning" feature, user directory search, and file sharing (direct connect and file transfer on a LAN, plus sending files over the internet). ICQ support additionally covers presence status and offline messaging.

The README describes the project as under active development and open to contributions. It links to separate quickstart guides for setting up AIM and ICQ clients against the server, a guide for compiling and running the server itself, and a Discord server for help and for getting involved. It also documents a Management API, specified as an OpenAPI spec, for administering the server from the command line: the README's own PowerShell and curl examples show creating a user (POST to /user with a screen name and password), deleting one (DELETE to /user), changing a password (PUT to /user/password), listing all active sessions (GET /session), and creating or listing public chat rooms (POST or GET to /chat/room/public), all issued as plain HTTP requests against a server on localhost port 8080. Open OSCAR Server is released under the MIT license.

The submission drew a modest but real response on Hacker News, gathering 17 points and 7 comments within about 5 hours of posting.

Key facts

Open OSCAR Server is an open-source, MIT-licensed instant-messaging server written in Go that provides a compatible backend for classic AIM and ICQ clients.
It supports Windows AIM clients versioned v1.x-v5.x and v6.x-v7.x and Windows ICQ clients numbered 98x, 99x, 2000x, 2001x, 2002x, 2003x, 4, and 5, plus TOC-protocol clients such as Pidgin, gaim, TiK, vAIM, Miranda, and iEM.
Feature coverage includes buddy lists, chat rooms, buddy icons, user profiles, privacy blocking, user directory search, file sharing, and, on ICQ, presence status and offline messaging.
The project ships a Management API, documented as an OpenAPI spec, for creating and deleting users, resetting passwords, listing sessions, and managing chat rooms from the command line.
The GitHub submission drew 17 points and 7 comments on Hacker News within about 5 hours, and the README describes the project as under active development with its own Discord server for contributors.

Why it matters

Classic AIM and ICQ clients only work if there is a server on the other end speaking their protocol. Open OSCAR Server is a from-scratch, open-source implementation of that server side, written in Go, that lets old Windows AIM and ICQ software, plus independent clients built for the TOC protocol (Pidgin, gaim, TiK, vAIM, Miranda, iEM), connect to a backend that anyone can compile and run themselves.

Who it affects

It affects anyone still running old AIM or ICQ client software on Windows: the README explicitly lists support for Windows AIM clients versioned v1.x-v5.x and v6.x-v7.x and Windows ICQ clients numbered 98x, 99x, 2000x, 2001x, 2002x, 2003x, 4, and 5, plus users of independent TOC-protocol clients such as Pidgin, gaim, TiK, vAIM, Miranda, and iEM. It also affects whoever wants to administer such a server: the Management API lets an operator create and delete user accounts, reset passwords, and manage chat rooms from the command line.

How to use it

Open OSCAR Server is MIT-licensed and hosted on GitHub. The README points to separate quickstart guides for setting up AIM and ICQ clients against the server, a guide for compiling and running the server itself, and a Discord server for help and for getting involved as a contributor. Administration goes through the Management API, documented as an OpenAPI spec: the README's own PowerShell and curl examples show creating a user, deleting a user, changing a password, listing all active sessions, and creating or listing public chat rooms, all as plain HTTP requests against a server on localhost port 8080.

How solid is it

The claims here come from the project's own GitHub README, which is detailed and internally consistent: it lists specific supported client versions for both AIM and ICQ, a full feature table, a working Management API with concrete request examples, and a screenshot of the Pidgin client actually connected to the server. On Hacker News, the submission had drawn 17 points and 7 comments within about 5 hours of posting, a modest but real amount of engagement for a niche retro-computing project.

Risks and caveats

There is no indication in the source that Open OSCAR Server is affiliated with, or endorsed by, AOL, ICQ, or whoever currently owns those brands; it is an independent, unofficial reimplementation. The README also gives no history of why the project was built, and no release date, version number, or adoption figures such as GitHub stars or downloads. Worth noting for anyone following the documented examples: the Management API calls for creating a user and changing a password send the screen name and password as plain JSON over plain HTTP to a local address, with no TLS shown in the README's own commands.

“This project is under active development. Contributions are welcome!”

— the Open OSCAR Server README