DoomHelix

DoomHelix is an agentic modal code editor based on Helix. It keeps Helix's fast modal editing, tree-sitter highlighting, LSP support, selections, splits, and command model, then adds an editor-native agent workflow for real coding work.

The editor command is dhx.

Why DoomHelix

DoomHelix is built around one idea: the agent should feel like part of the editor, not a separate terminal chore. Chat, explain, fix, refactor, patch review, approvals, and apply flow happen inside the editor with the current file, selection, diagnostics, theme, mode, visible buffers, and workspace context attached automatically.

Highlights

• Long-lived ACP agent sessions through codex-acp.
• Uses the Agent Client Protocol path pioneered by Zed's agent integration.
• Streaming transcript panel inside the editor.
• Prompt UI for chat and coding actions.
• Selection-aware explain, fix, refactor, and edit commands.
• Current-file context even when the agent panel is focused.
• Command/file approval prompts for agent tool use.
• Patch preview and confirmed git apply flow.
• Apply failure diagnostics shown in editor buffers.
• One managed agent panel to avoid message routing confusion.
• Configurable and runtime-movable panel position: left, right, top, or bottom.
• Configurable and keyboard-resizable panel size with <space>a + and <space>a -.
• Markdown transcript with selectable/copyable text and code fences.
• gd on transcript file links jumps back into the referenced source file.
• Agent transcript restore within the running editor session.
• Reuses Helix config paths and keeps agent settings in ~/.config/helix/agent.toml.

Agent Workflow

Common commands:

:agent chat          # prompt-backed chat turn
:agent explain       # explain selected code
:agent fix           # ask for a fix proposal
:agent refactor      # ask for a refactor proposal
:agent edit          # ask for a patch/diff edit
:agent patch         # preview latest patch
:agent apply         # confirm and apply latest patch
:agent panel         # open/focus transcript panel
:agent restore       # restore transcript panel
:agent position left # move transcript panel
:agent resize +5     # grow transcript panel
:agent resize -5     # shrink transcript panel
:agent status        # show agent runtime status
:agent restart       # restart the configured ACP backend

See docs/agent.md for the full command, configuration, and keymap reference.

Install

curl -fsSL https://raw.githubusercontent.com/borngraced/doom-helix/main/install.sh | sh

The installer downloads a prebuilt DoomHelix release when available and falls back to building from source. It prompts for an agent backend:

• Codex
• Claude
• Both
• Custom ACP / configure later

For non-interactive installs, set DOOMHELIX_AGENT:

curl -fsSL https://raw.githubusercontent.com/borngraced/doom-helix/main/install.sh | DOOMHELIX_AGENT=claude sh

Supported values are codex, claude, both, and none. Use none when you want to configure a custom ACP-compatible agent manually.

The installer places:

• dhx to ~/.local/bin/dhx
• dhx-bin to ~/.local/bin/dhx-bin
• selected ACP adapter binaries when requested
• runtime files to ~/.local/share/helix/runtime
• a runtime symlink next to dhx-bin so DoomHelix works without an existing Helix install
• starter agent config at ~/.config/helix/agent.toml if one does not already exist

DoomHelix relies on normal Helix runtime lookup order. That means existing Helix users keep their ~/.config/helix/runtime overrides, while fresh installs still work through the bundled sibling runtime/ directory.

Override install paths with DOOMHELIX_PREFIX, DOOMHELIX_BIN_DIR, or DOOMHELIX_RUNTIME_DIR. Override the agent config destination with DOOMHELIX_CONFIG_DIR or DOOMHELIX_AGENT_CONFIG_FILE.

On macOS, the generated dhx wrapper keeps a conservative PATH and only adds the PATH from the environment used to run install.sh. If your language servers live in user-local directories, run the installer with the PATH you want baked into the wrapper:

PATH="$HOME/.cargo/bin:$HOME/.local/bin:$PATH" sh install.sh

Force a local source build:

DOOMHELIX_BUILD_FROM_SOURCE=1 sh install.sh

Install only the editor:

DOOMHELIX_AGENT=none sh install.sh

Minimal Agent Config

enable = true
name = "codex"
command = "codex-acp"
args = []
panel-position = "right"
panel-size = 30

Put this in ~/.config/helix/agent.toml. Keep theme, editor settings, and keymaps in Helix's normal config.toml.

Agent Backend

DoomHelix talks to agents over ACP, the Agent Client Protocol used by Zed's agent integration. Codex uses Zed's codex-acp adapter, which bridges DoomHelix's ACP client to Codex's long-lived app-server backend. Claude uses Zed's @zed-industries/claude-code-acp adapter, installed as claude-code-acp. The installer installs npm-based adapters under DoomHelix's install prefix, so the default install stays inside ~/.local.

Upstream

DoomHelix is built from Helix. The original Helix project is available at https://github.com/helix-editor/helix.

License

DoomHelix keeps Helix's MPL-2.0 licensing for modified upstream source files. See LICENSE.