conduwuit/docs/differences.md

**Note: This list may not up to date. There are rapidly more and more

improvements, fixes, changes, etc being made that it is becoming more difficult to maintain this list. I recommend that you give conduwuit a try and see the differences for yourself. If you have any concerns, feel free to join the conduwuit Matrix room and ask any pre-usage questions.**

list of features, bug fixes, etc that conduwuit does that Conduit does not

Outgoing typing indicators, outgoing read receipts, and outgoing presence!

Performance

• Concurrency support for individual homeserver key fetching for faster remote room joins and room joins that will error less frequently
• Send Cache-Control response header with immutable and 1 year cache length for all media requests (download and thumbnail) to instruct clients to cache media, and reduce server load from media requests that could be otherwise cached
• Add feature flags and config options to enable/build with zstd, brotli, and/or gzip HTTP body compression (response and request)
• Eliminate all usage of the thread-blocking getaddrinfo(3) call upon DNS queries, significantly improving federation latency/ping and cache DNS results (NXDOMAINs, successful queries, etc) using hickory-dns / hickory-resolver
• Enable HTTP/2 support on all requests
• Vastly improve RocksDB default settings to use new features that help with performance significantly, uses settings tailored to SSDs, various ways to tweak RocksDB, and a conduwuit setting to tell RocksDB to use settings that are tailored to HDDs or slow spinning rust storage or buggy filesystems.
• Implement database flush and cleanup conduwuit operations when using RocksDB
• Implement RocksDB write buffer corking and coalescing in database write-heavy areas
• Perform connection pooling and keepalives where necessary to significantly improve federation performance and latency
• Various config options to tweak connection pooling, request timeouts, connection timeouts, DNS timeouts and settings, etc with good defaults which also help huge with performance via reusing connections and retrying where needed
• Properly get and use the amount of parallelism / tokio workers
• Implement building conduwuit with jemalloc (which extends to the RocksDB jemalloc feature for maximum gains) or hardened_malloc light variant, and io_uring support, and produce CI builds with jemalloc and io_uring by default for performance (Nix doesn't seem to build hardened_malloc-rs properly)
• Add support for caching DNS results with hickory-dns / hickory-resolver in conduwuit (not a replacement for a proper resolver cache, but still far better than nothing), also properly falls back on TCP for UDP errors or if a SRV response is too large
• Add config option for using DNS over TCP, and config option for controlling A/AAAA record lookup strategy (e.g. don't query AAAA records if you don't have IPv6 connectivity)
• Overall significant database, Client-Server, and federation performance and latency improvements (check out the ping room leaderboards if you don't believe me :>)
• Add config options for RocksDB compression and bottommost compression, including choosing the algorithm and compression level
• Use loole MPSC channels instead of tokio MPSC channels for huge performance boosts in sending channels (mainly relevant for federation) and presence channels
• Use tracing/log's release_max_level_info feature to improve performance, build speeds, binary size, and CPU usage in release builds by avoid compiling debug/trace log level macros that users will generally never use (can be disabled with a build-time feature flag)
• Remove some unnecessary checks on EDU handling for incoming transactions, effectively speeding them up
• Simplify, dedupe, etc huge chunks of the codebase, including some that were unnecessary overhead, binary bloats, or preventing compiler/linker optimisations
• Implement zero-copy RocksDB database accessors, substantially improving performance caused by unnecessary memory allocations

General Fixes/Features

• Add legacy Element client hack fixing password changes and deactivations on legacy Element Android/iOS due to usage of an unspecced user field for UIAA
• Raise and improve all the various request timeouts making some things like room joins and client bugs error less or none at all than they should, and make them all user configurable
• Add missing reason field to user ban events (/ban)
• Safer and cleaner shutdowns across incoming/outgoing requests (graceful shutdown) and the database
• Stop sending make_join requests on room joins if 15 servers respond with M_UNSUPPORTED_ROOM_VERSION or M_INVALID_ROOM_VERSION
• Stop sending make_join requests if 50 servers cannot provide make_join for us
• Respect most client parameters for /media/ requests (allow_redirect still needs work)
• Return joined member count of rooms for push rules/conditions instead of a hardcoded value of 10
• Make CONDUIT_CONFIG optional, relevant for container users that configure only by environment variables and no longer need to set CONDUIT_CONFIG to an empty string.
• Allow HEAD and PATCH (MSC4138) HTTP requests in CORS for clients (despite not being explicity mentioned in Matrix spec, HTTP spec says all HEAD requests need to behave the same as GET requests, Synapse supports HEAD requests)
• Fix using conduwuit with flake-compat on NixOS
• Resolve and remove some "features" from upstream that result in concurrency hazards, exponential backoff issues, or arbitrary performance limiters
• Find more servers for outbound federation /hierarchy requests instead of just the room ID server name
• Support for suggesting servers to join through at /_matrix/client/v3/directory/room/{roomAlias}
• Support for suggesting servers to join through us at /_matrix/federation/v1/query/directory
• Misc edge-case search fixes (e.g. potentially missing some events)
• Misc /sync fixes (e.g. returning unnecessary data or incorrect/invalid responses)
• Add replaces_state and prev_sender in unsigned for state event changes which primarily makes Element's "See history" button on a state event functional
• Fix Conduit not allowing incoming federation requests for various world readable rooms
• Fix Conduit not respecting the client-requested file name on media requests
• Prevent sending junk / non-membership events to /send_join and /send_leave endpoints
• Only allow the requested membership type on /send_join and /send_leave endpoints (e.g. don't allow leave memberships on join endpoints)
• Prevent state key impersonation on /send_join and /send_leave endpoints
• Validate X-Matrix origin and request body "origin" field on incoming transactions
• Add GET /_matrix/client/v1/register/m.login.registration_token/validity endpoint
• Explicitly define support for sliding sync at /_matrix/client/versions (org.matrix.msc3575)
• Fix seeing empty status messages on user presences

Moderation

• (Also see Admin Room for all the admin commands pertaining to moderation, there's a lot!)
• Add support for room banning/blocking by ID using admin command
• Add support for serving support well-known from [global.well_known] (MSC1929) (/.well-known/matrix/support)
• Config option to forbid publishing rooms to the room directory (lockdown_public_room_directory) except for admins
• Admin commands to delete room aliases and unpublish rooms from our room directory
• For all /report requests: check if the reported event ID belongs to the reported room ID, raise report reasoning character limit to 750, fix broken formatting, make a small delayed random response per spec suggestion on privacy, and check if the sender user is in the reported room.
• Support blocking servers from downloading remote media from, returning a 404
• Don't allow m.call.invite events to be sent in public rooms (prevents calling the entire room)
• On new public room creations, only allow moderators to send m.call.invite, org.matrix.msc3401.call, and org.matrix.msc3401.call.member events to prevent unprivileged users from calling the entire room
• Add support for a "global ACLs" feature (forbidden_remote_server_names) that blocks inbound remote room invites, room joins by room ID on server name, room joins by room alias on server name, incoming federated joins, and incoming federated room directory requests. This is very helpful for blocking servers that are purely toxic/bad and serve no value in allowing our users to suffer from things like room invite spam or such. Please note that this is not a substitute for room ACLs.
• Add support for a config option to forbid our local users from sending federated room directory requests for (forbidden_remote_room_directory_server_names). Similar to above, useful for blocking servers that help prevent our users from wandering into bad areas of Matrix via room directories of those malicious servers.
• Add config option for auto remediating/deactivating local non-admin users who attempt to join bad/forbidden rooms (auto_deactivate_banned_room_attempts)
• Deactivating users will remove their profile picture, blurhash, display name, and leave all rooms by default just like Synapse and for additional privacy
• Reject some EDUs from ACL'd users such as read receipts and typing indicators

Privacy/Security

• Add config option for device name federation with a privacy-friendly default (disabled)
• Add config option for requiring authentication to the /publicRooms endpoint (room directory) with a default enabled for privacy
• Add config option for federating /publicRooms endpoint (room directory) to other servers with a default disabled for privacy
• Uses proper argon2 crate by RustCrypto instead of questionable rust-argon2 crate
• Generate passwords with 25 characters instead of 15
• Config option ip_range_denylist to support refusing to send requests (typically federation) to specific IP ranges, typically RFC 1918, non-routable, testnet, etc addresses like Synapse for security (note: this is not a guaranteed protection, and you should be using a firewall with zones if you want guaranteed protection as doing this on the application level is prone to bypasses).
• Config option to block non-admin users from sending room invites or receiving remote room invites. Admin users are still allowed.
• Config option to disable incoming and/or outgoing remote read receipts
• Config option to disable incoming and/or outgoing remote typing indicators
• Config option to disable incoming, outgoing, and/or local presence and for timing out remote users
• Sanitise file names for the Content-Disposition header for all media requests (thumbnails, downloads, uploads)
• Media repository on handling Content-Disposition and Content-Type is fully spec compliant and secured
• Send secure default HTTP headers such as a strong restrictive CSP (see MSC4149), deny iframes, disable X-XSS-Protection, disable interest cohort in Permission-Policy, etc to mitigate any potential attack surface such as from untrusted media

Administration/Logging

• Commandline argument to specify the path to a config file instead of relying on CONDUIT_CONFIG
• Revamped admin room infrastructure and commands
• Substantially clean up, improve, and fix logging (less noisy dead server logging, registration attempts, more useful troubleshooting logging, proper error propagation, etc)
• Configurable RocksDB logging (LOG files) with proper defaults (rotate, max size, verbosity, etc) to stop LOG files from accumulating so much
• Explicit startup error if your configuration allows open registration without a token or such like Synapse with a way to bypass it if needed
• Replace the lightning bolt emoji option with support for setting any arbitrary text (e.g. another emoji) to suffix to all new user registrations, with a conduwuit default of "🏳️‍⚧️"
• Implement config option to auto join rooms upon registration
• Warn on unknown config options specified
• Add /_conduwuit/server_version route to return the version of conduwuit without relying on the federation API /_matrix/federation/v1/version
• Add /_conduwuit/local_user_count route to return the amount of registered active local users on your homeserver if federation is enabled
• Add configurable RocksDB recovery modes to aid in recovering corrupted RocksDB databases
• Support config options via CONDUWUIT_ prefix and accessing non-global struct config options with the __ split (e.g. CONDUWUIT_WELL_KNOWN__SERVER)
• Add support for listening on multiple TCP ports and multiple addresses
• Opt-in Sentry.io telemetry and metrics, mainly used for crash reporting
• Log the client IP on various requests such as registrations, banned room join attempts, logins, deactivations, federation transactions, etc
• Fix Conduit dropping some remote server federation response errors

Maintenance/Stability

• GitLab CI ported to GitHub Actions
• Add support for the Matrix spec compliance test suite Complement via the Nix flake and various other fixes for it
• Implement running and diff'ing Complement results in CI and error if any mismatch occurs to prevent large cases of conduwuit regressions
• Repo is (officially) mirrored to GitHub, GitLab, git.gay, git.girlcock.ceo, sourcehut, and Codeberg (see README.md for their links)
• Docker container images published to GitLab Container Registry, GitHub Container Registry, and Dockerhub
• Extensively revamp the example config to be extremely helpful and useful to both new users and power users
• Fixed every single clippy (default lints) and rustc warnings, including some that were performance related or potential safety issues / unsoundness
• Add a lot of other clippy and rustc lints and a rustfmt.toml file
• Repo uses Renovate, Trivy, and keeps ALL dependencies as up to date as possible
• Purge unmaintained/irrelevant/broken database backends (heed, sled, persy) and other unnecessary code or overhead
• webp support for images
• Add cargo audit support to CI
• Add documentation lints via lychee and markdownlint-cli to CI
• CI tests for all sorts of feature matrixes (jemalloc, non-defaullt, all features, etc)
• Add static and dynamic linking smoke tests in CI to prevent any potential linking regressions for Complement, static binaries, Nix devshells, etc
• Add timestamp by commit date when building OCI images for keeping image build reproducibility and still have a meaningful "last modified date" for OCI image
• Add timestamp by commit date via SOURCE_DATE_EPOCH for Debian packages
• Startup check if conduwuit running in a container and is listening on 127.0.0.1 (generally containers are using NAT networking and 0.0.0.0 is the intended listening address)
• Add a panic catcher layer to return panic messages in HTTP responses if a panic occurs
• Add full compatibility support for SHA256 media file names instead of base64 file names to overcome filesystem file name length limitations (OS error file name too long) while still retaining upstream database compatibility
• Remove SQLite support due to being very poor performance, difficult to maintain against RocksDB, and is a blocker to significantly improved database code

Admin Room

• Add support for a console CLI interface that can issue admin commands and output them in your terminal
• Add support for an admin-user-only commandline admin room interface that can be issued in any room with the \\!admin or \!admin prefix and returns the response as yourself in the same room
• Add admin commands for uptime, server startup, server shutdown, and server restart
• Fix admin room handler to not panic/crash if the admin room command response fails (e.g. too large message)
• Add command to dynamically change conduwuit's tracing log level filter on the fly
• Add admin command to fetch a server's /.well-known/matrix/support file
• Add debug admin command to force update user device lists (could potentially resolve some E2EE flukes)
• Implement RocksDB online backups, listing RocksDB backups, and listing database file counts all via admin commands
• Add various database visibility commands such as being able to query the getters and iterators used in conduwuit, a very helpful online debugging utility
• Forbid the admin room from being made public or world readable history
• Add !admin as a way to call the admin bot
• Extend clear cache admin command to support clearing more caches such as DNS and TLS name overrides
• Admin debug command to send a federation request/ping to a server's /_matrix/federation/v1/version endpoint and measures the latency it took
• Add admin command to bulk delete media via a codeblock list of MXC URLs.
• Add admin command to delete both the thumbnail and media MXC URLs from an event ID (e.g. from an abuse report)
• Add admin command to list all the rooms a local user is joined in
• Add admin command to list joined members in a room
• Add admin command to view the room topic of a room
• Add admin command to delete all remote media in the past X minutes as a form of deleting media that you don't want on your server that a remote user posted in a room, a --force flag to ignore errors, and support for reading last modified time instead of creation time for filesystems that don't support file created metadata
• Add admin command to return a room's full/complete state
• Admin debug command to fetch a PDU from a remote server and inserts it into our database/timeline as backfill
• Add admin command to delete media via a specific MXC. This deletes the MXC from our database, and the file locally.
• Add admin commands for banning (blocking) room IDs from our local users joining (admins are always allowed) and evicts all our local users from that room, in addition to bulk room banning support, and blocks room invites (remote and local) to the banned room, as a moderation feature
• Add admin commands to output jemalloc memory stats and memory usage
• Add admin command to get rooms a remote user shares with us
• Add debug admin commands to get the earliest and latest PDU in a room
• Add debug admin command to echo a message
• Add admin command to insert rooms tags for a user, most useful for inserting the m.server_notice tag on your admin room to make it "persistent" in the "System Alerts" section of Element
• Add experimental admin debug command for Dendrite's AdminDownloadState (/admin/downloadState/{serverName}/{roomID}) admin API endpoint to download and use a remote server's room state in the room
• Disable URL previews by default in the admin room due to various command outputs having "URLs" in them that clients may needlessly render/request
• Extend memory usage admin server command to support showing memory allocator stats such as jemalloc's
• Add admin debug command to see memory allocator's full extended debug statistics such as jemalloc's

Misc

• Add guest support for accessing TURN servers via turn_allow_guests like Synapse
• Support for creating rooms with custom room IDs like Maunium Synapse (room_id request body field to /createRoom)
• Query parameter ?format=event|content for returning either the room state event's content (default) for the full room state event on /_matrix/client/v3/rooms/{roomId}/state/{eventType}[/{stateKey}] requests (see https://github.com/matrix-org/matrix-spec/issues/1047)
• Send a User-Agent on all of our requests
• Send avatar_url on invite room membership events/changes
• Support sending well_known response to client login responses if using config option [well_known.client]
• Implement include_state search criteria support for /search requests (response now can include room states)
• Declare various missing Matrix versions and features at /_matrix/client/versions
• Implement legacy Matrix /v1/ media endpoints that some clients and servers may still call
• Config option to change Conduit's behaviour of homeserver key fetching (query_trusted_key_servers_first). This option sets whether conduwuit will query trusted notary key servers first before the individual homeserver(s), or vice versa which may help in joining certain rooms.
• Implement unstable MSC2666 support for querying mutual rooms with a user
• Implement unstable MSC3266 room summary API support
• Implement unstable MSC4125 support for specifying servers to join via on federated invites
• Make conduwuit build and be functional under Nix + macOS
• Log out all sessions after unsetting the emergency password
• Assume well-knowns are broken if they exceed past 12288 characters.
• Add support for listening on both HTTP and HTTPS if using direct TLS with conduwuit for usecases such as Complement
• Add config option for disabling RocksDB Direct IO if needed
• Add various documentation on maintaining conduwuit, using RocksDB online backups, some troubleshooting, using admin commands, moderation documentation, etc
• (Developers): Add support for hot reloadable/"live" modular development
• (Developers): Add support for tokio-console
• (Developers): Add support for tracing flame graphs
• No cryptocurrency donations allowed, conduwuit is fully maintained by independent queer maintainers, and with a strong priority on inclusitivity and comfort for protected groups 🏳️‍⚧️
• Add a community Code of Conduct for all conduwuit community spaces, primarily the Matrix space