diff --git a/.github/workflows/README.md b/.github/workflows/README.md
index a9d7ea69..21278c29 100644
--- a/.github/workflows/README.md
+++ b/.github/workflows/README.md
@@ -82,7 +82,8 @@ the job sets from its own token. Run them locally with `bats tests`, or
   no longer matches the inputs fails. nixfmt, from the flake's own nixpkgs,
   checks every `*.nix` file.
 - **shell:** builds the dev shell on each system (Linux x86_64 and arm64, and
-  an Apple Silicon Mac) and checks `jj` and `just` run inside.
+  an Apple Silicon Mac) and checks `jj`, `just` and `tb` run inside. `tb` is
+  built from source, so this is also its only build on darwin and arm64.
 - **home:** switches the devcontainer profile for a `vscode` user that already
   has a `~/.zshrc`, like the image's oh-my-zsh one. home-manager must take it
   over, keeping the old one as `~/.zshrc.backup`. Then
diff --git a/.github/workflows/nix.yml b/.github/workflows/nix.yml
index bd569cca..67640a85 100644
--- a/.github/workflows/nix.yml
+++ b/.github/workflows/nix.yml
@@ -48,7 +48,7 @@ jobs:
       - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
       - uses: cachix/install-nix-action@13d8dd58da0234aa297dedd986986ccb8e7f3e24 # v31.11.1
       - name: Dev shell
-        run: nix develop --no-update-lock-file -c sh -c 'jj --version && just --version'
+        run: nix develop --no-update-lock-file -c sh -c 'jj --version && just --version && tb --version'
 
   # The devcontainer profile, switched for a real vscode user whose ~/.zshrc
   # already exists, as the image's oh-my-zsh one does: home-manager takes it
diff --git a/lib/packages.nix b/lib/packages.nix
index bfd91e97..21962933 100644
--- a/lib/packages.nix
+++ b/lib/packages.nix
@@ -17,6 +17,28 @@ let
     patches = [ ];
     postInstall = "installManPage doc/cheat.1";
   });
+
+  # taskbook's Rust port (mise has it as github:taskbook-sh/taskbook). Its own
+  # overlay.nix installs the release binaries as they are, which on Linux ask
+  # for /lib64/ld-linux and so don't run on NixOS; built from source instead.
+  # The workspace's server (axum, sqlx, Postgres) is left out.
+  taskbook = pkgs.rustPlatform.buildRustPackage (finalAttrs: {
+    pname = "taskbook";
+    version = "1.5.0";
+    src = pkgs.fetchFromGitHub {
+      owner = "taskbook-sh";
+      repo = "taskbook";
+      tag = "v${finalAttrs.version}";
+      hash = "sha256-zG/w3xUg6dicFFx1Bd/fcsRAS6RxibPp8mwB9fy5fog=";
+    };
+    cargoHash = "sha256-NLuOE7rdvgqPOEa06u36b+EmWOLWEC3ygJM8lo19ksQ=";
+    cargoBuildFlags = [ "--package=taskbook-client" ];
+    cargoTestFlags = [
+      "--package=taskbook-client"
+      "--package=taskbook-common"
+    ];
+    meta.mainProgram = "tb";
+  });
 in
 [
   pkgs.bat
@@ -27,6 +49,7 @@ in
   pkgs.gh
   pkgs.claude-code
   pkgs.tmux
+  taskbook
   # formatters for `jj fix`
   pkgs.taplo
   pkgs.rumdl
diff --git a/tools/mise/global.toml b/tools/mise/global.toml
index 73a5acd9..56c5bddd 100644
--- a/tools/mise/global.toml
+++ b/tools/mise/global.toml
@@ -1,5 +1,10 @@
-# Global mise tools, linked to ~/.config/mise/conf.d/dotfiles.toml: only what
-# the global justfile needs outside this repo. The repo's own tools stay in the
-# root mise.toml.
+# Global mise tools, linked to ~/.config/mise/conf.d/dotfiles.toml: the few
+# tools needed outside this repo. The repo's own tools stay in the root
+# mise.toml.
 [tools]
+# The global justfile's recipes.
 just = "latest"
+# taskbook (`tb`), from the Rust port: one binary instead of the original's
+# Node runtime, same ~/.taskbook data format. Its sync swaps local storage for
+# a server, with no offline copy, so it stays off.
+"github:taskbook-sh/taskbook" = "1.5"