Add DeltaChat Channel

The adapter drives the @deltachat/stdio-rpc-server JSON-RPC subprocess directly — pure Node.js against the DeltaChat core library. Messages are delivered over email with Autocrypt/OpenPGP encryption.

Install

1. Copy the adapter and its registration test

Fetch the channels branch from the configured remote that carries it, then overwrite the skill-owned files with the canonical registry copies:

src/channels/deltachat.ts
src/channels/deltachat-registration.test.ts

2. Append the self-registration import

Append to src/channels/index.ts (skip if already present):

import './deltachat.js';

3. Install the adapter package (pinned)

@deltachat/stdio-rpc-server@2.49.0

4. Build and validate

pnpm run build

pnpm exec vitest run src/channels/deltachat-registration.test.ts

Both must be clean before proceeding. deltachat-registration.test.ts is the one integration test: it imports the real channel barrel and asserts the registry contains deltachat. It goes red if the import './deltachat.js'; line is deleted or drifts, if the barrel fails to evaluate (so the channel genuinely would not register), or if @deltachat/stdio-rpc-server isn't installed (the import throws) — so it also implicitly verifies the dependency from step 4. Importing is safe: deltachat instantiates the rpc client only in setup() (at host startup), never at import.

End-to-end message delivery against a real email account is verified manually once the service is running — see Wiring and Troubleshooting.

Account Setup

A dedicated email account is strongly recommended — it will accumulate DeltaChat-formatted messages and store encryption keys. Not all providers work well with DeltaChat; check https://providers.delta.chat/ before picking one.

Default security modes: IMAP uses SSL/TLS (port 993), SMTP uses STARTTLS (port 587). Both are configurable via .env — see Credentials below.

To find the correct hostnames for a domain:

node -e "require('dns').resolveMx('example.com', (e,r) => console.log(r))"

Most providers publish their IMAP/SMTP hostnames in their help docs under "manual setup" or "IMAP access."

Credentials

Add to .env:

DC_EMAIL=bot@example.com
DC_PASSWORD=your-app-password
DC_IMAP_HOST=imap.example.com
DC_IMAP_PORT=993
DC_IMAP_SECURITY=1        # 1=SSL/TLS (default), 2=STARTTLS, 3=plain
DC_SMTP_HOST=smtp.example.com
DC_SMTP_PORT=587
DC_SMTP_SECURITY=2        # 2=STARTTLS (default), 1=SSL/TLS, 3=plain

Security settings are applied on every startup, so changing them in .env and restarting takes effect without wiping the account.

Optional settings

The following are read from the process environment (not .env). To override them, add Environment= lines to the systemd service unit or your launchd plist:

Variable	Default	Description
DC_ACCOUNT_DIR	dc-account	Directory for DeltaChat account data (IMAP state, keys, blobs)
DC_DISPLAY_NAME	NanoClaw	Bot display name shown in DeltaChat
DC_AVATAR_PATH	(none)	Absolute path to avatar image; set at startup only

The /set-avatar command (send an image with that caption) is the easiest way to set the avatar at runtime without modifying the service file. Only users with owner or global admin role can use it.

Restart

Run from your NanoClaw project root:

source setup/lib/install-slug.sh

# Linux
systemctl --user restart $(systemd_unit)

# macOS
launchctl kickstart -k gui/$(id -u)/$(launchd_label)

On first start the adapter configures the email account (IMAP/SMTP credentials, calls configure()). Subsequent starts skip straight to startIo(). Account data is stored in dc-account/ in the project root (or your DC_ACCOUNT_DIR).

Wiring

DMs

DeltaChat contacts cannot be added by email alone — to start a chat, the user must open the bot's invite link in their DeltaChat app or scan its QR code. This triggers the SecureJoin handshake.

Step 1 — Get the invite link

After the service starts, the adapter logs the invite URL and writes a QR SVG:

grep "invite link" logs/nanoclaw.log | tail -1
# url field contains the https://i.delta.chat/... invite link
# also written to dc-account/invite-qr.svg (or $DC_ACCOUNT_DIR/invite-qr.svg)

The invite URL is stable (tied to the bot's email and encryption keys) so it stays valid across restarts.

Step 2 — Add the bot in DeltaChat

Two options for the user to connect:

• Link: Copy the https://i.delta.chat/... URL and open it on the device running DeltaChat. The app recognises it and shows a "Start chat" prompt.
• QR code: Open dc-account/invite-qr.svg in a browser or image viewer, display it on screen, and scan it from the DeltaChat app using the QR-scan button on the new-chat screen.

After accepting, DeltaChat exchanges keys and creates the chat automatically.

Step 3 — Wire the chat to an agent

Once the first message arrives the router auto-creates a messaging_groups row. Look up the chat ID:

pnpm exec tsx scripts/q.ts data/v2.db \
  "SELECT platform_id, name FROM messaging_groups WHERE channel_type='deltachat' AND is_group=0 ORDER BY created_at DESC LIMIT 5"

Then run /init-first-agent — it creates the agent group, grants the user owner access, and wires the messaging group in one step:

pnpm exec tsx scripts/init-first-agent.ts \
  --channel deltachat \
  --user-id deltachat:user@example.com \
  --platform-id <platform_id from above> \
  --display-name "Your Name"

Groups

Add the bot email to a DeltaChat group. When any member sends a message, the router creates a messaging_groups row with is_group = 1. Run /manage-channels to wire it to an agent group, or wire it directly with ncl — the host service must be running (ncl connects to it over a Unix socket):

# Engage mode/pattern default to the DeltaChat adapter's declared channel
# defaults — for DeltaChat groups that's a name pattern (the platform has no
# mention metadata), so the agent responds when addressed by name.
ncl wirings create --messaging-group-id <mg-id> --agent-group-id <ag-id>

Next Steps

If you're in the middle of /setup, return to the setup flow now.

Otherwise, run /init-first-agent to create an agent and wire it to your DeltaChat DM (see Wiring above), or /manage-channels to wire this channel to an existing agent group.

Channel Info

• type: deltachat
• terminology: DeltaChat calls them "chats" (1:1 DMs) and "groups"
• supports-threads: no — DeltaChat has no thread model
• platform-id-format: numeric chat ID as a string (e.g. "12") — the DeltaChat core's internal chat identifier
• user-id-format: deltachat:{email} — the contact's email address
• how-to-find-id: Send a message from DeltaChat to the bot email, then query messaging_groups as shown above
• typical-use: Personal assistant over DeltaChat DMs; small groups where participants use DeltaChat
• default-isolation: One agent per bot identity. Multiple chats with the same operator can share an agent group; groups with other people should typically get their own agent group (the default shared session mode already gives each messaging group its own session)

Features

• File attachments — inbound and outbound; inbound waits up to 30 seconds for large-message download to complete
• Invite link logged on every startup — URL + QR SVG written to dc-account/invite-qr.svg; see Wiring for the bootstrap flow
• /set-avatar — send an image with this caption to change the bot's DeltaChat avatar (admin/owner only)
• Connectivity watchdog — restarts IO if IMAP goes quiet for 20 minutes or connectivity drops below threshold for two consecutive 5-minute checks
• Network nudge — maybeNetwork() called every 10 minutes to recover from prolonged idle

Not supported: DeltaChat reactions, message editing/deletion, read receipts.

Connectivity model

isConnected() returns true when the internal connectivity value is ≥ 3000:

Range	Meaning
1000–1999	Not connected
2000–2999	Connecting
3000–3999	Working (IMAP fetching)
≥ 4000	Fully connected (IMAP IDLE)

Troubleshooting

Adapter not starting — credentials missing

grep "Channel credentials missing" logs/nanoclaw.log | grep deltachat

All six required vars (DC_EMAIL, DC_PASSWORD, DC_IMAP_HOST, DC_IMAP_PORT, DC_SMTP_HOST, DC_SMTP_PORT) must be present in .env.

Account configure fails

grep "DeltaChat" logs/nanoclaw.log | tail -20

Common causes:

• Wrong IMAP/SMTP hostnames — double-check provider docs
• App password not generated — Gmail and some others require this when 2FA is enabled
• Port/security mismatch — defaults are port 993 + SSL/TLS for IMAP and port 587 + STARTTLS for SMTP; override with DC_IMAP_PORT/DC_IMAP_SECURITY or DC_SMTP_PORT/DC_SMTP_SECURITY in .env

Provider uses SMTP port 465 (SSL/TLS) instead of 587

Set DC_SMTP_SECURITY=1 and DC_SMTP_PORT=465 in .env, then restart.

Messages not arriving

1. Check the service is running and the adapter started: grep "Channel adapter started.*deltachat" logs/nanoclaw.log
2. Check connectivity: grep "DeltaChat: IO started" logs/nanoclaw.log
3. Check the sender has been granted access — run /init-first-agent to create their user record and wire the chat
4. Verify the messaging group is wired: pnpm exec tsx scripts/q.ts data/v2.db "SELECT mg.platform_id, mga.agent_group_id FROM messaging_groups mg JOIN messaging_group_agents mga ON mg.id = mga.messaging_group_id WHERE mg.channel_type='deltachat'"

Stale lock file after crash

rm -f dc-account/accounts.lock
systemctl --user restart "$(. setup/lib/install-slug.sh && systemd_unit)"

Bot not responding after restart

The account is already configured — IO restarts automatically on service start. If the RPC subprocess is stuck, restart the service. Check for errors:

grep "DeltaChat" logs/nanoclaw.error.log | tail -20

Messages received but agent not responding

The messaging group exists but may not be wired to an agent group. Run:

pnpm exec tsx scripts/q.ts data/v2.db "SELECT id, platform_id, name FROM messaging_groups WHERE channel_type='deltachat'"

If the group has no entry in messaging_group_agents, wire it with /manage-channels.