Differences from upstream Conduit

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 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 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
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.
Add a Cargo build profile for aggressive build-time performance optimisations for release builds (1 codegen unit, no debug, fat LTO, etc, and optimise all crates with same)
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
Implement building conduwuit with jemalloc (which extends to the RocksDB jemalloc feature for maximum gains) or hardened_malloc light variant, and produce CI builds with jemalloc 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)
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)

General Fixes:

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)
Fixed spec compliance issue with room version 8 - 11 joins (https://github.com/matrix-org/synapse/issues/16717 / https://github.com/matrix-org/matrix-spec/issues/1708)
Safer and cleaner shutdowns on both database side as we run cleanup on shutdown and exits database loop better (no potential hanging issues in database loop), overall cleaner shutdown logic
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)
Increased graceful shutdown timeout from a low 60 seconds to 180 seconds to avoid killing connections and let the remaining ones finish processing
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 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)
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
Add workaround for Out Of Your Element appservice bridge to make it functional on conduwuit (bug has already been reported)

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 [well_known.support] (MSC1929)
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
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.

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

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 configurable RocksDB recovery modes to aid in recovering corrupted RocksDB databases
Support config options via CONDUWUIT_ prefix
Add support for listening on multiple TCP ports
Disable update check by default as it's not useful for conduwuit
Opt-in Sentry.io telemetry and metrics, mainly used for crash reporting

Maintenance/Stability:

GitLab CI ported to GitHub Actions
Repo is mirrored to GitHub, GitLab, git.gay, sourcehut, and Codeberg (see README.md for their links)
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
Has Renovate, Trivy, and keeps ALL dependencies as up to date as possible
Attempts and interest in removing extreme and unnecessary panics/unwraps/expects that can lead to denial of service or such (upstream and upstream contributors want this unusual behaviour for some reason)
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
CI tests with all features
Add timestamp by commit date support to building OCI images for keeping image build reproducibility and still have a meaningful "last modified date" for OCI image metadata
Update rusqlite/sqlite (not that you should be using it)
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)

Admin Room:

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 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
Add admin command to return a room's 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 conduwuit's uptime
Add admin command to get rooms a remote user shares with us

Misc:

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)
Add optional feature flag to use SHA256 key names for media instead of base64 to overcome filesystem file name length limitations (OS error file name too long)
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
Assume well-knowns are broken if they exceed past 10000 characters.
Add support for the Matrix spec compliance test suite Complement via the Nix flake and various other fixes for it
Add support for listening on both HTTP and HTTPS if using direct TLS with conduwuit for usecases such as Complement
Implement running and diff'ing Complement results in CI
Interest in supporting other operating systems such as macOS, BSDs, and Windows, and getting them added into CI and doing builds for them
Add config option for disabling RocksDB Direct IO if needed
(Developers): Add support for tokio-console
(Developers): Add support for tracing flame graphs
Add release-debuginfo Cargo build profile
No cryptocurrency donations allowed, conduwuit is fully maintained by independent queer maintainers, and with a strong priority on inclusitivity and comfort for protected groups 🏳️‍⚧️