AlTerm Terminal Emulator

Built in C for AltOS • Started February 2026

What Is This?

AlTerm is a terminal emulator I'm building from scratch in C. It's going to be the core text interface for AltOS. I'm not using existing terminal libraries or copying how other terminals work - I'm building everything myself.

Why Build Another Terminal?

Because every existing terminal emulator is bloated. GNOME Terminal drags in the entire GTK stack. Alacritty needs Rust. Kitty has Python overhead. They're fine, but they're built for regular Linux distributions that don't care about efficiency.

AltOS is built around low RAM usage and unified configuration. I need a terminal that fits that. So I'm making one.

What's Working?

Phase 0 is done. I have a working Wayland window, keyboard input, and an event loop. It doesn't actually display text or run shell commands yet, but the foundation works.

What's Next?

Phase 1 is text rendering - FreeType integration, character grid, scrolling, cursor. After that, Phase 2 is the actual terminal emulation part - PTY integration, ANSI escape sequences, shell process management.

Why C?

Because modern terminals use 50-100MB of RAM just sitting idle doing nothing. That's stupid. A terminal should use 10-20MB max.

C lets me control exactly how much memory gets used. No garbage collection, no runtime bloat, just system calls and efficient code.

Development Setup

I'm building this on my ThinkPad X220 running Linux Mint. Old hardware forces me to care about performance. The code's on GitHub at RockMods61901/alterm.

Timeline

No deadlines. Phase 0 took about a week. Phase 1 will probably take longer because text rendering is complicated. Phase 2 (terminal emulation) will be the longest - getting ANSI escape sequences right is where most terminals get messy.

End Goal

A terminal that uses 10-20MB of RAM, integrates with AltOS's unified config system, supports standard terminal features, runs natively on Wayland, and is fast enough to actually use daily.

Once it's stable, it'll be the default terminal for AltOS. Should work on any Wayland Linux distribution though.

Following Development

I'll post updates here when I hit major milestones. Check the blog for development posts.

Code's on GitHub at RockMods61901/alterm.

- James