tacterm

A terminal emulator based on Rio, focused on performance, simplicity, and practical improvements.

Website · Fork status and differences from Rio · Source · Upstream documentation

Raison d’être

tacterm exists to develop and ship the improvements we want in the terminal we use every day.

Rio provides a strong foundation. This fork gives useful fixes and new ideas an independent path to release, including changes that remain pending upstream.

Our priorities are straightforward:

• Performance: keep input and rendering responsive, and reduce unnecessary CPU, GPU, and memory use.
• Simplicity: keep everyday use straightforward and the code maintainable.
• Features with a performance budget: evaluate new capabilities for their effect on latency and resource use.

tacterm will continue incorporating upstream Rio changes and contributing fixes back where appropriate, while maintaining its own development priorities and release schedule.

Built on the work of Raphael Amorim and the Rio contributors.

Current status

The main development and integration branch is main. It combines our tab title, WSL, GPU memory, window sizing, and Windows presentation fixes. See FORK_STATUS.md for the implemented changes, compatibility requirements, and known limits.

Release archives use tacterm / tacterm.exe and Tacterm.app; source builds also produce tacterm / tacterm.exe. Some in-app labels retain Rio's names.

Current source builds use their own configuration directory:

• Windows: %USERPROFILE%\AppData\Local\tacterm
• macOS: ~/.config/tacterm
• Linux: $XDG_CONFIG_HOME/tacterm, or ~/.config/tacterm

Set TACTERM_CONFIG_HOME to override this directory. When it does not yet exist, tacterm copies the Rio configuration directory (including themes and other assets, excluding log and install-backups) into it. RIO_CONFIG_HOME overrides the import source only. Rio's files remain unchanged; subsequent loads, edits and reloads use tacterm's copy. An existing tacterm directory, even empty, disables import. If Rio has no directory, tacterm initializes an empty one and uses defaults.

A failed copy leaves the destination unpublished and reports a configuration error; it never falls back to reading Rio directly. Linked or special files require manual migration. Absolute paths inside settings are copied verbatim. The already published 0.1.0-alpha.1 release still shares Rio's configuration directory; the isolation above applies to builds containing this change.

The application uses its own lime t_ icon, adapted from the website, with native assets for Windows, macOS, and Linux. See icon sources.

The upstream Rio installation guides, packages, screenshots, and releases describe Rio. They are not tacterm distributions. Available tacterm builds, platform requirements, and signing details are listed on the website and GitHub Releases.

Building from source

Rio's current minimum supported Rust version is 1.96.1. With the platform dependencies installed, build a development executable from the repository root:

cargo build --locked -p rioterm

This produces target/debug/tacterm (or target/debug/tacterm.exe on Windows). Building does not install the executable. Consult the upstream documentation for general configuration and platform guidance; fork-specific behavior is documented here.

Tab title fonts

Set a separate font for Rio-rendered tab titles in config.toml:

[navigation]
tab-font-family = "Segoe UI"
tab-font-size = 13

The family must be installed on your system. An omitted, empty, or unavailable family uses the terminal font. The size is in logical pixels, defaults to 12, and is limited to 8–20 to fit the tab strip. Changes apply when the config is reloaded and do not change the terminal font. These fields support platform overrides under [platform.windows.navigation] (or linux/macos).

Relationship with Rio

Rio remains the upstream project. General fixes intended for Rio are developed in separate branches so each upstream pull request stays focused. The tacterm main branch integrates the changes intended for this fork.

Rio documentation: rioterm.com. Support upstream development: Sponsor Raphael Amorim.

License

MIT. Original authorship and license notices are preserved.