diff --git a/modules/user/helix.nix b/modules/user/helix.nix
new file mode 100644
index 0000000..7adc72e
--- /dev/null
+++ b/modules/user/helix.nix
@@ -0,0 +1,192 @@
+{ inputs, pkgs, lib, config, ... }: let
+  # glibc >= 2.44 defines bsearch() as a C23 const-generic macro, which clashes
+  # with the copy vendored by some tree-sitter grammars (tree-sitter-perl).
+  # Drop the vendored implementation, same as nixpkgs does for upstream helix.
+  patchedStdenv = pkgs.stdenv // {
+    mkDerivation = args: pkgs.stdenv.mkDerivation (args // {
+      postPatch = (args.postPatch or "") + ''
+        if [ -e src/bsearch.c ]; then
+          rm src/bsearch.c
+          substituteInPlace src/tsp_unicode.h \
+            --replace-fail '#include "bsearch.c"' ""
+        fi
+      '';
+    });
+  };
+
+  helixGrammars = pkgs.callPackage "${inputs.helix-steel}/grammars.nix" {
+    stdenv = patchedStdenv;
+  };
+
+  helixSteel =
+    (
+      pkgs.callPackage "${inputs.helix-steel}/default.nix" {
+        gitRev = inputs.helix-steel.rev;
+
+        # The upstream flake builds the grammars with its own callPackage,
+        # swap in the patched ones.
+        callPackage = path: args:
+          if toString path == toString "${inputs.helix-steel}/grammars.nix" then helixGrammars
+          else pkgs.callPackage path args;
+      }
+    )
+    .overrideAttrs (old: {
+      cargoBuildFlags = (old.cargoBuildFlags or []) ++ [
+        "--features"
+        "steel,git"
+      ];
+    });
+
+  comment-headers = pkgs.fetchurl {
+    url = "https://github.com/codingvivi/comment-dividers.hx/raw/refs/heads/main/comment_headers.scm";
+    name = "comment_headers.scm";
+    hash = "sha256-ohgn6DFJl0rdRJuri6Frs/uUlUsPxMvPHDuw4FS3qEE=";
+  };
+
+  patched-comment-headers = pkgs.runCommand "comment_headers.scm" { } ''
+    install -m 0644 ${comment-headers} "$out"
+
+    ${pkgs.python3}/bin/python3 - <<'PY'
+    from pathlib import Path
+    import os
+    import sys
+
+    p = Path(os.environ["out"])
+    s = p.read_text()
+
+    start_marker = "(define (get-block-delims)"
+    end_marker = "(define (delete_till_first_nonwhitespace!)"
+
+    try:
+        start = s.index(start_marker)
+        end = s.index(end_marker, start)
+    except ValueError as e:
+        sys.exit(f"failed to find function markers: {e}")
+
+    new_get_block_delims = """(define (get-block-delims)
+      (helix.static.open_above)
+      (helix.static.insert_string "test_string")
+      (helix.static.normal_mode)
+      (helix.static.extend_to_line_bounds)
+      (helix.static.trim_selections)
+      (helix.static.toggle_comments)
+      (let* ([commented-test-string (helix.static.current-highlighted-text!)]
+             [strings-without-whitespace (split-whitespace commented-test-string)])
+        (delete-line-noyank!)
+        (cond
+          [(and (> (length strings-without-whitespace) 1)
+                (equal? (last strings-without-whitespace) "test_string"))
+           (list (first strings-without-whitespace) "")]
+          [(> (length strings-without-whitespace) 2)
+           (list (first strings-without-whitespace) (last strings-without-whitespace))]
+          [else
+           (list "" "")])))
+
+    """
+
+    s = s[:start] + new_get_block_delims + s[end:]
+
+    old = "(make-line line-length fill-pattern #f padding-pattern)"
+    new = "(make-line line-length \"\" fill-pattern padding-pattern)"
+
+    if old not in s:
+        sys.exit("failed to find insert-divider make-line call")
+
+    s = s.replace(old, new)
+
+    p.write_text(s)
+    PY
+  '';
+in {
+  home.packages = with pkgs; [
+    steel
+    wakatime-cli
+  ];
+
+  # Wakapi is WakaTime-compatible, so the same plugin/client works.
+  sops.templates.".wakatime.cfg" = {
+    path = "${config.home.homeDirectory}/.wakatime.cfg";
+    mode = "0600";
+    content = ''
+      [settings]
+      api_url = https://coding.srcoder.moe/api
+      api_key = ${config.sops.placeholder."tokens/apis/wakapi"}
+    '';
+  };
+
+  home.activation.installWakatimeHx = lib.hm.dag.entryAfter [ "writeBoundary" ] ''
+    export PATH="${pkgs.steel}/bin:$PATH"
+    export STEEL_HOME="${config.xdg.dataHome}/steel"
+
+    if [ ! -f "$STEEL_HOME/cogs/wakatime/wakatime.scm" ]; then
+      forge pkg install --git https://github.com/Xerxes-2/wakatime.hx.git
+    fi
+  '';
+
+  programs.helix = {
+    enable = true;
+    package = helixSteel;
+    defaultEditor = true;
+
+    settings = {
+      # theme = "catppuccin-mocha";
+      editor = {
+        insert-final-newline = false;
+        indent-guides.render = true;
+
+        whitespace.render = {
+          space = "all";
+          tab = "all";
+          nbsp = "none";
+          nnbsp = "none";
+          newline = "none";
+        };
+
+        cursor-shape = {
+          normal = "block";
+          insert = "bar";
+          select = "underline";
+        };
+      };
+
+      keys.normal = {
+        space = {
+          C-c = {
+            h = ":comment-h1";
+            j = ":comment-h2";
+            k = ":comment-h3";
+            d = ":comment-divider";
+          };
+        };
+
+        S-down = ["extend_to_line_bounds" "delete_selection" "paste_after"];
+        S-up = ["extend_to_line_bounds" "delete_selection" "move_line_up" "paste_before"];
+      };
+    };
+  };
+
+  xdg.configFile = {
+    "helix/cogs/comment_headers.scm".source = patched-comment-headers;
+    "helix/helix.scm".text = ''
+      (require (prefix-in div. "cogs/comment_headers.scm"))
+
+      (provide comment-h1 comment-h2 comment-h3 comment-divider)
+
+      (define (comment-h1)
+        (div.insert-h1!))
+
+      (define (comment-h2)
+        (div.insert-h2!))
+
+      (define (comment-h3)
+        (div.insert-h3!))
+
+      (define (comment-divider)
+        (div.insert-divider! 80 "~"))
+    '';
+    "helix/init.scm".text = ''
+      ;; Steel init file
+      (require "wakatime/wakatime.scm")
+    '';
+  };
+}