tacterm: status and differences from Rio

Last reviewed: 2026-10-20.

This file describes the changes integrated into tacterm's main branch. Update it when a change is integrated, upstream accepts an equivalent fix, or validation and release status changes. Proposed changes are not implemented features.

Upstream baseline

Upstream: raphamorim/rio.
Repository: narma/tacterm.
Integrated upstream baseline: 59203ccd5f. This was also the fetched upstream/main tip at this review.
Main development and integration branch: main (formerly my-fork).
Upstream workspace version: 0.5.28. Independent tacterm release versions are committed in packaging/VERSION.

Implemented changes

Area	Changes relative to the baseline	Main commits / evidence
Executable name	Cargo builds `tacterm` / `tacterm.exe` directly. Release packaging, local build helper, desktop launchers and CLI naming use the new binary name. The Cargo package remains `rioterm`.	`frontends/rioterm/Cargo.toml`, `frontends/rioterm/src/cli.rs`, `packaging/release.mjs`
Application icon	Adapt the website's lime `t_` mark for the window icon, Windows EXE resources, macOS app bundles, and Linux desktop integration. Include multiple sizes, Retina representations, and a reproducible vector source. Use a matching Linux app/desktop ID so Wayland can resolve the icon.	Icon assets and generator; `frontends/rioterm/build.rs`, `frontends/rioterm/src/router/window.rs`, `packaging/release.mjs`
Tab title rendering	Improve mixed Unicode title shaping, fallback font selection, baseline alignment, vertical centering, and pixel alignment. Cache shaped title runs. Support `tab-font-family` and `tab-font-size`, including platform overrides, without changing terminal fallback fonts.	`b7e076cd80`, `24d69c3767`, `a6bc99ab69`, `966f2870f7`, `a99b322020`, `d0252f0ae8`; settings example in README
macOS title fonts	Check preferred title font coverage with CoreText, including collection fonts and fonts without backing file data.	`7a67599194`; macOS-specific tests require macOS
Configuration reload	Reapply platform overrides when loading an updated configuration, preserving platform-specific settings after reload.	`06b88fb63d`
Independent configuration	Use a dedicated `tacterm` directory and `TACTERM_CONFIG_HOME`. Import Rio settings and assets once when the destination is absent, excluding logs and installer backups; preserve the source and never fall back to it.	`rio-backend/src/config/migration.rs`; configuration details in README
WSL working directories	Open a new tab in the focused tab's directory when inheritance is enabled. Automatically load the WSL zsh working-directory integration; restore the shell directory at prompts and ignore subshell reports.	`126454e0ce`, `fc05f6d77f`, `4ec4cc646e`
New tab dimensions	Preserve full window dimensions and the original font size when creating tabs, avoiding repeated subtraction of panel padding and progressive loss of terminal area.	`8dc3e939bd`; context regression test covers repeated tab creation at 150% scale
GPU allocation policy	Reduce GPU memory reservations and defer unused atlas storage.	`ebf9ddf67b`
Grid rendering resources	Remove unused grid frame buffers and share wgpu grid pipelines between panels in the same window.	`1fcf03d0e9`, `cee1de68d7`; shared-pipeline GPU readback regression test
Color glyph atlases	Grow color atlases on demand rather than allocating full-size textures immediately; preserve cached pixels and glyph coordinates during growth.	`be47166333`; GPU regression tests
Grayscale glyph atlases	Start smaller and grow grayscale atlases on demand; refresh bindings when atlas size changes.	`9571ae44a7`; GPU regression tests
Windows timing	Preserve precision for refresh-rate fractions and large QPC counts in the fallback vsync interval calculation.	`d62532facd`; two regression tests
Windows VRR presentation	Continuously present focused, visible, non-occluded fullscreen or maximized GPU windows. Reuse resident grid data for idle frames and pace successful frames through the swapchain instead of adding a DWM wait. Fall back to display-paced retries after failed surface acquisition.	`cafbad552c`, `812ae341ab`; unchanged-row and cursor-update GPU readback regression test

Performance and limits

GPU memory savings depend on the backend, driver, number of panels, and glyph workload. Growing atlases retain their capacity after clear, so a heavy workload can reach the original maximum texture storage. Reduced allocation does not by itself establish a throughput or latency improvement.

Continuous presentation performs GPU work even when terminal contents are idle; it trades idle resource use for steady presentation in the specified window states. Other window states keep event-driven rendering. Behavior still needs validation across displays and GPUs.

Workstation measurement reports and ad hoc benchmark helpers are kept locally, outside the published repository. Regression tests remain part of the source.

Validation

The configuration import and executable rename passed Windows validation on 2026-10-20: 221 backend tests (including 5 import regressions), the renamed application's compile check, 4 packaging tests, 9 website tests, formatting and whitespace checks. The local memory-aware release build and installation passed version and SHA256 checks. The user confirmed familiar appearance after first launch; the imported configuration matched Rio's original, which was unchanged. Both pinned launchers were updated to the new executable with their arguments preserved. Native macOS and Linux import behavior still needs validation.

The website build passed with live release metadata. Source-build naming and configuration compatibility text are updated, and the internal screenshot-format maintenance section has been removed from the public status page. The homepage introduction now describes the project's ongoing direction rather than individual fixes; the static build and all 9 website tests passed on 2026-10-20 after this copy update.

Release 0.1.0 is published from 7e8a12f8b2 with all six native OS/architecture archives, checksums and feature-focused release notes. The release workflow passed every native build and packaging check. The downloaded Windows x64 archive and executable matched their published SHA256 values and reported tacterm 0.1.0. The native test workflow also passed on Windows, macOS and Linux. Measurements summarized in those notes compare individual optimization stages on one Windows workstation; they are not cumulative or a single final-release-versus-upstream benchmark. Detailed local reports and helpers remain excluded from the repository.

Integration checks on 2026-10-20, on Windows with Rust stable 1.99.0, passed against the combined code through merge commit 4500440f8d:

Check	Result
`cargo +stable test -p rio-window --lib --locked -j 4`	7 passed, including both vsync conversion regression tests
`cargo +stable test -p sugarloaf --features wgpu --lib --locked -j 4`	133 passed, 8 ignored
`cargo +stable test -p rioterm --bin rio --locked -j 4`	228 passed; 1 WSL/zsh integration test ignored
Explicit ignored shared-pipeline GPU readback test	1 passed; covers panel isolation, resize, buffer growth, unchanged-row presentation, and cursor updates
`WGPU_BACKEND=dx12` with `cargo +stable test -p sugarloaf --features wgpu --test gpu_memory --locked -j 4 -- --ignored --nocapture`	2 passed; color and grayscale atlas pixels survive growth and clear on DX12
`cargo +stable fmt --all -- --check`, whitespace, local documentation links	Passed

The local build/installation scripts also passed PowerShell syntax checks, and the memory-aware release helper passed -DryRun. No release build or installation was performed for this transition. macOS-only tests and the ignored WSL/zsh integration test were not executed here.

The subsequent history cleanup removed local benchmark artifacts without changing application code or GPU regression tests. The retained commits were checked against their original trees, excluding only the removed artifacts.

The native project CI also passed formatting, Clippy, and the regular test suite on Windows, macOS, and Linux for release source commit e04e22900c. The separate MSYS2 check is PR-only and was skipped. Packaging validation (4 tests) and website download metadata validation (5 tests) passed as well.

The first release build compiled and packaged all six native OS/architecture targets from e04e22900c. Every packaged executable passed --version and --help; Linux dependency resolution and macOS ad-hoc signatures also passed. The downloaded Windows x64 archive and executable matched their recorded SHA256 hashes, and its native --version check reported tacterm 0.1.0-alpha.1 on the workstation. These are build, packaging, and CLI checks; no graphical sessions were tested for this release.

For the subsequent application-icon update, the generated assets passed a regeneration check; the multi-size ICO and 1024 px ICNS decoded successfully. A local Windows development build passed, and the icon extracted from its EXE matched the new ICO's opaque pixels and transparent background. macOS Dock and Linux desktop appearance still require native visual checks.

Release and compatibility status

The website presentation was refreshed on 2026-10-20 with larger typography, responsive change and download cards, and light/dark/system theme controls on the home, status, and error pages. Theme preference persists across navigation; system mode follows live OS changes. Website metadata and theme behavior checks passed (9 tests). Browser checks covered light/dark appearance, a 390 px mobile layout, six release download links, and theme persistence after reload and navigation. This is a website-only change; it does not change native builds. The homepage's illustrative terminal was replaced with an actual Windows development-build screenshot showing three native tabs and a real theme-test run. The caption identifies the custom theme and development build, and the image can be opened at full size. The homepage now explains practical differences before downloads, with compatibility questions and source-build instructions following them. Concise editorial summaries link to this complete status document, which includes section navigation. Builds without release metadata link to GitHub Releases instead of incorrectly implying that no release exists.

Release archives package the command as tacterm / tacterm.exe; macOS uses Tacterm.app with its own bundle ID. Source builds now produce tacterm, and some in-app labels retain Rio compatibility. Current source builds use an independent configuration directory with one-time Rio import. Published 0.1.0-alpha.1 binaries still share Rio configuration paths.
Version 0.1.0 is the first non-preview release, with independent settings and the tacterm executable name.
Independent releases are built by the tacterm release workflow for Windows, macOS, and Linux, each on native x64 and ARM64 runners. Preview 0.1.0-alpha.1 is published with all six archives and SHA256 checksums. The website offers downloads validated against the actual GitHub release assets.
Windows binaries are unsigned; macOS apps are ad-hoc signed and not notarized. Windows requires the matching Microsoft Visual C++ v14 Runtime; Linux requires its graphics and font libraries in addition to glibc 2.35+. Native CLI smoke checks cover version and help output. GUI/GPU sessions and older-OS compatibility still require separate validation.
Existing personal builds and settings remain in place. Public release builds do not install or replace the workstation executable.
Subsequent builds use tacterm's own application icon. The published 0.1.0-alpha.1 preview predates this icon change.

Release automation

packaging/ defines release versions, the native build matrix, archive contents, smoke checks, and publishing. Tags use tacterm-vVERSION. Publishing requires an existing tag pointing to the exact build commit; pushing that tag starts the complete workflow automatically.
Windows uses portable ZIP archives, macOS ZIP archives contain Tacterm.app, and Linux uses tar.gz archives. Requirements are recorded per artifact.
All six targets must pass before a release is published. Checks verify artifact source/version consistency and SHA256 hashes; a draft is published only after all downloads are uploaded. Published versions are not overwritten.
Releases include SHA256SUMS, a machine-readable release.json, installation instructions, and license notices. The site refreshes automatically after publication.
The first preview's six public download URLs returned HTTP 200 with matching file sizes. All archive hashes agreed between GitHub asset digests, the release manifest, and SHA256SUMS; the manifest's own checksum also passed.
Packaging validation tests cover a complete matrix, corrupted archives, mixed source commits, and mismatched release tags. Local release-mode CLI compilation was checked without building or installing a local Windows release executable.

Project website

tacterm website: an independent project homepage with source in website/ on main.
The site moved to https://tacterm.dev/ on 2026-10-20. Root-relative stylesheet, script, and image URLs were checked on all three published pages; HTTPS is enforced by GitHub Pages.
The change count and review date are generated from this document. Homepage summaries explain selected implemented changes; the complete technical status is published as status.html. Download metadata comes from the release manifest.
A GitHub Actions workflow builds and publishes relevant changes to GitHub Pages. It replaces the inherited Rio site previously served from gh-pages.
The site uses static HTML, CSS, and small theme and clipboard scripts, without third-party fonts, analytics, or runtime content dependencies.

Next work

Evaluate upstream fixes individually, rechecking their current status and behavior before integrating them. Proposed changes are not implemented features.
Add trusted signing and macOS notarization, and validate configuration import on macOS and Linux before the next release.
Continue incorporating upstream changes and keep upstream PRs scoped to one problem each.