diff --git a/README.md b/README.md
index d2cdb73..022ddea 100644
--- a/README.md
+++ b/README.md
@@ -26,6 +26,7 @@ make down      # Stop
 - Async IRC over plain TCP or TLS (SASL PLAIN auth, IRCv3 CAP negotiation)
 - Microsoft Teams support via outgoing webhooks (no SDK dependency)
 - Telegram support via long-polling (no SDK dependency, SOCKS5 proxied)
+- Mumble support via TCP/TLS protobuf control channel (text only, SOCKS5 proxied)
 - Plugin system with `@command` and `@event` decorators
 - Hot-reload: load, unload, reload plugins at runtime
 - Admin permission system (hostmask patterns + IRCOP detection + AAD IDs)
diff --git a/ROADMAP.md b/ROADMAP.md
index dac1f81..205f57f 100644
--- a/ROADMAP.md
+++ b/ROADMAP.md
@@ -149,3 +149,13 @@
 - [ ] Adaptive Cards for richer formatting (Teams)
 - [ ] Graph API integration for DMs and richer channel access (Teams)
 - [ ] Teams event handlers (member join/leave)
+
+## v2.2.0 -- Protocol Expansion
+
+- [x] Mumble adapter via TCP/TLS protobuf control channel (text chat only)
+- [ ] Discord adapter via WebSocket gateway + REST API
+- [ ] Matrix adapter via long-poll `/sync` endpoint
+- [ ] XMPP adapter via persistent TCP + XML stanzas (MUC support)
+- [ ] Slack adapter via Socket Mode WebSocket
+- [ ] Mattermost adapter via WebSocket API
+- [ ] Bluesky adapter via AT Protocol firehose + REST API
diff --git a/TASKS.md b/TASKS.md
index bc3fe3d..314d62e 100644
--- a/TASKS.md
+++ b/TASKS.md
@@ -1,6 +1,20 @@
 # derp - Tasks
 
-## Current Sprint -- v2.1.0 Telegram Integration (2026-02-21)
+## Current Sprint -- v2.2.0 Mumble Adapter (2026-02-21)
+
+| Pri | Status | Task |
+|-----|--------|------|
+| P0 | [x] | `src/derp/mumble.py` -- MumbleBot, MumbleMessage, protobuf codec |
+| P0 | [x] | TCP/TLS connection through SOCKS5 proxy |
+| P0 | [x] | Minimal protobuf encoder/decoder (no external protobuf dep) |
+| P0 | [x] | Mumble protocol: Version, Authenticate, Ping, TextMessage |
+| P0 | [x] | Channel/user state tracking from ChannelState/UserState messages |
+| P0 | [x] | `src/derp/config.py` -- `[mumble]` defaults |
+| P0 | [x] | `src/derp/cli.py` -- conditionally start MumbleBot |
+| P1 | [x] | Tests: `test_mumble.py` (93 cases, 1470 total) |
+| P2 | [x] | Documentation update (USAGE.md, CHEATSHEET.md, API.md, README.md, ROADMAP.md) |
+
+## Previous Sprint -- v2.1.0 Telegram Integration (2026-02-21)
 
 | Pri | Status | Task |
 |-----|--------|------|
diff --git a/TODO.md b/TODO.md
index f8ac86c..cdd5dd9 100644
--- a/TODO.md
+++ b/TODO.md
@@ -105,6 +105,61 @@ is preserved in git history for reference.
 - [ ] Markdown/HTML formatting mode toggle
 - [ ] Webhook mode (for setWebhook instead of getUpdates)
 
+## Discord
+
+- [ ] Discord adapter via WebSocket gateway + REST API (no SDK)
+- [ ] DiscordBot + DiscordMessage (duck-typed with IRC Message)
+- [ ] Gateway intents for message content
+- [ ] Message splitting at 2000-char limit
+- [ ] Permission tiers via user/role IDs
+- [ ] Slash command registration (optional)
+
+## Matrix
+
+- [ ] Matrix adapter via long-poll `/sync` endpoint (no SDK)
+- [ ] MatrixBot + MatrixMessage (duck-typed with IRC Message)
+- [ ] Room-based messaging (rooms map to channels)
+- [ ] Power levels map to permission tiers
+- [ ] E2EE support (optional, requires libolm)
+
+## XMPP
+
+- [ ] XMPP adapter via persistent TCP + XML stanzas (no SDK)
+- [ ] XMPPBot + XMPPMessage (duck-typed with IRC Message)
+- [ ] MUC (Multi-User Chat) support -- rooms map to channels
+- [ ] SASL authentication
+- [ ] TLS/STARTTLS connection
+
+## Mumble
+
+- [x] Mumble adapter via TCP/TLS + protobuf control channel (no SDK)
+- [x] MumbleBot + MumbleMessage (duck-typed with IRC Message)
+- [x] Text chat only (no voice)
+- [x] Channel-based messaging
+- [x] Minimal protobuf encoder/decoder (no protobuf dep)
+
+## Slack
+
+- [ ] Slack adapter via Socket Mode WebSocket (no SDK)
+- [ ] SlackBot + SlackMessage (duck-typed with IRC Message)
+- [ ] OAuth token + WebSocket for events
+- [ ] Channel/DM messaging
+- [ ] Permission tiers via user IDs
+
+## Mattermost
+
+- [ ] Mattermost adapter via WebSocket API (no SDK)
+- [ ] MattermostBot + MattermostMessage (duck-typed with IRC Message)
+- [ ] Self-hosted Slack alternative
+- [ ] Channel/DM messaging
+
+## Bluesky
+
+- [ ] Bluesky adapter via AT Protocol firehose + REST API (no SDK)
+- [ ] BlueskyBot + BlueskyMessage (duck-typed with IRC Message)
+- [ ] Mention-based command dispatch
+- [ ] Post/reply via `com.atproto.repo.createRecord`
+
 ## Testing
 
 - [x] Plugin command unit tests (encode, hash, dns, cidr, defang)
diff --git a/docs/API.md b/docs/API.md
index 99fd567..473dde4 100644
--- a/docs/API.md
+++ b/docs/API.md
@@ -357,6 +357,87 @@ Same stable attributes and methods as `Bot`:
 
 ---
 
+## `derp.mumble` -- Mumble Adapter
+
+Alternative bot adapter for Mumble via TCP/TLS protobuf control channel
+(text chat only). All TCP routed through SOCKS5 proxy. Uses a minimal
+built-in protobuf encoder/decoder (no external dependency). Exposes the
+same plugin API as `derp.bot.Bot`.
+
+### `MumbleMessage` dataclass
+
+Duck-typed compatible with IRC `Message`:
+
+| Field | Type | Description |
+|-------|------|-------------|
+| `raw` | `dict` | Decoded protobuf fields |
+| `nick` | `str \| None` | Sender username (from session lookup) |
+| `prefix` | `str \| None` | Sender username (for ACL) |
+| `text` | `str \| None` | Message body (HTML stripped) |
+| `target` | `str \| None` | channel_id as string (or `"dm"`) |
+| `is_channel` | `bool` | `True` for channel msgs, `False` for DMs |
+| `command` | `str` | Always `"PRIVMSG"` (compat shim) |
+| `params` | `list[str]` | `[target, text]` |
+| `tags` | `dict[str, str]` | Empty dict (no IRCv3 tags) |
+
+### `MumbleBot`
+
+Same stable attributes and methods as `Bot`:
+
+| Attribute | Type | Description |
+|-----------|------|-------------|
+| `name` | `str` | Always `"mumble"` |
+| `config` | `dict` | Merged TOML configuration |
+| `nick` | `str` | Bot username (from config) |
+| `prefix` | `str` | Command prefix (from `[mumble]` or `[bot]`) |
+| `state` | `StateStore` | Persistent key-value storage |
+| `registry` | `PluginRegistry` | Shared command and event registry |
+
+**Sending messages** -- same signatures, Mumble protobuf transport:
+
+| Method | Behaviour |
+|--------|-----------|
+| `send(target, text)` | TextMessage to channel (HTML-escaped) |
+| `reply(msg, text)` | `send(msg.target, text)` |
+| `long_reply(msg, lines, *, label="")` | Paste overflow, same logic as IRC |
+| `action(target, text)` | Italic HTML text (`<i>...</i>`) |
+| `shorten_url(url)` | Same FlaskPaste integration |
+
+**IRC no-ops** (debug log, no error):
+
+`join`, `part`, `kick`, `mode`, `set_topic`
+
+**Plugin management** -- delegates to shared registry:
+
+`load_plugins`, `load_plugin`, `reload_plugin`, `unload_plugin`
+
+**Permission tiers** -- same model, exact username string matching:
+
+`_get_tier(msg)`, `_is_admin(msg)`
+
+### Protobuf Codec (internal)
+
+Minimal protobuf wire format helpers -- not part of the stable API:
+
+| Function | Description |
+|----------|-------------|
+| `_encode_varint(value)` | Encode unsigned int as protobuf varint |
+| `_decode_varint(data, offset)` | Decode varint, returns `(value, offset)` |
+| `_encode_field(num, wire_type, value)` | Encode a single protobuf field |
+| `_decode_fields(data)` | Decode payload into `{field_num: [values]}` |
+| `_pack_msg(msg_type, payload)` | Wrap payload in 6-byte Mumble header |
+| `_unpack_header(data)` | Unpack header into `(msg_type, length)` |
+
+### Helper Functions
+
+| Function | Signature | Description |
+|----------|-----------|-------------|
+| `_strip_html` | `(text: str) -> str` | Strip HTML tags and unescape entities |
+| `_escape_html` | `(text: str) -> str` | Escape text for Mumble HTML messages |
+| `_build_mumble_message` | `(fields, users, our_session) -> MumbleMessage \| None` | Build message from decoded TextMessage fields |
+
+---
+
 ## Handler Signatures
 
 All command and event handlers are async functions receiving `bot` and
diff --git a/docs/CHEATSHEET.md b/docs/CHEATSHEET.md
index c0ef64e..bff2d64 100644
--- a/docs/CHEATSHEET.md
+++ b/docs/CHEATSHEET.md
@@ -521,6 +521,26 @@ Long-polling via `getUpdates` -- no public endpoint needed. All HTTP
 through SOCKS5 proxy. Strips `@botusername` suffix in groups. Messages
 split at 4096 chars. IRC-only commands are no-ops. ~90% of plugins work.
 
+## Mumble Integration
+
+```toml
+# config/derp.toml
+[mumble]
+enabled = true
+host = "mumble.example.com"
+port = 64738
+username = "derp"
+password = ""
+tls_verify = false                   # self-signed certs common
+admins = ["admin_user"]              # Mumble usernames
+operators = []
+trusted = []
+```
+
+TCP/TLS via SOCKS5 proxy. Text chat only (no voice). Minimal protobuf
+codec (no external dep). HTML stripped on receive, escaped on send.
+IRC-only commands are no-ops. ~90% of plugins work.
+
 ## Plugin Template
 
 ```python
diff --git a/docs/USAGE.md b/docs/USAGE.md
index 0cb215f..0831326 100644
--- a/docs/USAGE.md
+++ b/docs/USAGE.md
@@ -1474,3 +1474,83 @@ this automatically: `!help@mybot` becomes `!help`.
 All HTTP traffic (API calls, long-polling) routes through the SOCKS5
 proxy at `127.0.0.1:1080` via `derp.http.urlopen`. No direct outbound
 connections are made.
+
+## Mumble Integration
+
+Connect derp to a Mumble server via TCP/TLS protobuf control channel.
+Text chat only (no voice). All TCP is routed through the SOCKS5 proxy.
+No protobuf library dependency -- uses a minimal built-in varint/field
+encoder/decoder for the ~7 message types needed.
+
+### How It Works
+
+The bot connects to the Mumble server over TLS (via SOCKS5), sends
+Version and Authenticate messages, then enters a read loop. It tracks
+channels (ChannelState), users (UserState), and dispatches commands
+from TextMessage messages through the shared plugin registry.
+
+### Configuration
+
+```toml
+[mumble]
+enabled = true
+host = "mumble.example.com"        # Mumble server hostname
+port = 64738                        # Default Mumble port
+username = "derp"                   # Bot username
+password = ""                       # Server password (optional)
+tls_verify = false                  # Mumble commonly uses self-signed certs
+admins = ["admin_user"]             # Mumble usernames
+operators = []                      # Mumble usernames
+trusted = []                        # Mumble usernames
+```
+
+### Mumble Setup
+
+1. **Ensure a Mumble server** (Murmur/Mumble-server) is running and
+   accessible through the SOCKS5 proxy
+
+2. **Configure the bot** with the server hostname, port, and credentials
+
+3. **Configure permissions** using Mumble registered usernames. Use
+   `!whoami` to discover your username as the bot sees it.
+
+### Permission Tiers
+
+Same 4-tier model as IRC, but matches exact Mumble usernames instead of
+fnmatch hostmask patterns:
+
+```toml
+[mumble]
+admins = ["admin_user"]
+operators = ["oper_user"]
+trusted = ["trusted_user"]
+```
+
+### Plugin Compatibility
+
+Same compatibility as Teams/Telegram -- ~90% of plugins work without
+modification.
+
+| Feature | IRC | Mumble |
+|---------|-----|--------|
+| `bot.reply()` | Sends PRIVMSG | TextMessage to channel |
+| `bot.send()` | Sends PRIVMSG | TextMessage to channel |
+| `bot.action()` | CTCP ACTION | Italic HTML text (`<i>...</i>`) |
+| `bot.long_reply()` | Paste overflow | Paste overflow (same logic) |
+| `bot.state` | Per-server SQLite | Per-server SQLite |
+| `bot.join/part/kick/mode` | IRC commands | No-op (logged at debug) |
+| Event handlers (JOIN, etc.) | Fired on IRC events | Not triggered |
+| Hostmask ACL | fnmatch patterns | Exact usernames |
+
+### Text Encoding
+
+Mumble uses HTML for text messages. On receive, the bot strips tags and
+unescapes entities. On send, text is HTML-escaped. Action messages use
+`<i>` tags for italic formatting.
+
+### Transport
+
+All TCP connections route through the SOCKS5 proxy at `127.0.0.1:1080`
+via `derp.http.create_connection`. TLS is applied on top of the proxied
+socket. Mumble commonly uses self-signed certificates, so `tls_verify`
+defaults to `false`.