0.4.5 - 2026-08-01

Release Notes

Added

• ARF_R_HOME and ARF_R_VERSION can now select the R installation through environment variables (#271).

• --with-r-version and :switch now accept version ranges (^4.4, ~4.4, >=4.3, <5.0, *) in addition to exact and partial version numbers such as 4.4.2 and 4.4 (#271). Range operators come from the convention Cargo and npm use; R's own version numbers are plain major.minor.patch releases, so prerelease identifiers and build metadata are rejected.

• Experimental: arf can now read the R version a project has pinned and start that version instead of the configured default (#271, #288).
  It is opt-in through experimental.r_source_overrides in the arf.toml config.

  For example, the following configuration looks for two TOML files named rproject.toml and rproj.toml in the current directory, in order:

  [experimental]
  r_source_overrides = [
    { type = "toml-key", file = "rproject.toml", key = "project.r_version" },
    { type = "toml-key", file = "rproj.toml", key = "r.version" },
  ]

  If arf finds an R version defined in one of these files, it will select a matching version from the list of versions installed by rig and start that R.
  If none of them yields a matching version, arf falls back to the R selected by startup.r_source.

  The first of the two, rproject.toml, is used by rv.
  It looks like this:

  [project]
  r_version = "4.4"

  The second, rproj.toml, is a draft proposal from Tidyup 9.
  Unlike rv's rproject.toml, it also supports Cargo-style version ranges:

  [r]
  version = ">= 4.1.0, < 4.5.0"

  For now, it seems neither of these formats is widely adopted, so arf introduces a generic toml-key type that allows us to specify the filename and key path and supports Cargo-style version ranges.
  Of course, we can also support other TOML files with different names and keys for specifying the R version.

• Experimental: arf ipc list now reports a session_type field ("headless" or "interactive") for each session, so external clients can tell an agent-started headless session from an interactive REPL a person is using before sending it a shutdown. Sessions started by an older arf report null, which clients should treat as unknown (#283).

• Experimental: arf ipc session, arf ipc list, and arf headless --json now report r_home, the R installation the session is using, so an editor can use the same R instead of discovering one for itself. Sessions started by an older arf omit it, which clients should treat as unknown (#294).

• Experimental: arf r resolve lets external tools such as editors learn which R arf would use without starting R. It always emits JSON on success (#290, #291, #293).

Changed

• Partial version numbers passed to --with-r-version and :switch (e.g. 4.4) now match only that release series (4.4.x) instead of any version starting with the same text (#271).

Fixed

• arf could fail to start a different R version when R_HOME was set in the environment to point at another R installation (#295).
• Switching R versions with :switch no longer leaves stale .libPaths() entries from the previous R version, including after a :restart. R-related variables you set before starting arf are kept, apart from R_HOME and LD_LIBRARY_PATH, which are always removed. :restart still leaves the environment untouched (#295).
• Flags placed before a subcommand no longer get silently ignored; arf now reports the error and explains where the flag belongs (#275).
• Experimental: Commands sent with arf ipc send are now recorded in the history database, so they can be recalled with Ctrl+R, the history browser, and the up arrow like typed commands. Previously they were echoed and evaluated but only saved in some cases, depending on when the request arrived (#268).
• Experimental: IPC requests containing incomplete R expressions are now rejected before they can enter the continuation prompt.

Install arf-console 0.4.5

Install prebuilt binaries via shell script

curl --proto '=https' --tlsv1.2 -LsSf https://github.com/eitsupi/arf/releases/download/v0.4.5/arf-console-installer.sh | sh

Install prebuilt binaries via powershell script

powershell -ExecutionPolicy Bypass -c "irm https://github.com/eitsupi/arf/releases/download/v0.4.5/arf-console-installer.ps1 | iex"

Download arf-console 0.4.5

File	Platform	Checksum
arf-console-aarch64-apple-darwin.tar.xz	Apple Silicon macOS	checksum
arf-console-x86_64-apple-darwin.tar.xz	Intel macOS	checksum
arf-console-aarch64-pc-windows-msvc.zip	ARM64 Windows	checksum
arf-console-x86_64-pc-windows-msvc.zip	x64 Windows	checksum
arf-console-aarch64-unknown-linux-gnu.tar.xz	ARM64 Linux	checksum
arf-console-x86_64-unknown-linux-gnu.tar.xz	x64 Linux	checksum
arf-console-aarch64-unknown-linux-musl.tar.xz	ARM64 MUSL Linux	checksum
arf-console-x86_64-unknown-linux-musl.tar.xz	x64 MUSL Linux	checksum