Release notes

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Misc

• We have aligned trace identifiers across our trade records, FIX drop copy and tracing: a trace id is now written as a 32-character hexadecimal value, so the id stored with a trade is the one used to look up that order's trace. Orders that still send the previous sender_unique trace id format in FIX tag 820 continue to be accepted.

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Bug fixes

• We have fixed an issue where, with guaranteed delivery enabled for a gateway, a quick reconnect could leave the gateway without execution reports until it reconnected again, or cause some reports to be skipped.
• We have fixed an issue where the order book snapshot recorded for a fill could show the book from an earlier attempt the liquidity provider had rejected, and where those rejected attempts used memory until the matching engine was restarted.
• We fixed duplicate execution reports for orders whose fills are split between two or more external liquidity providers and the B-book in one match: each internal fill is now reported once and the order reaches the Filled status.

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Bug fixes

• We have made multiple fixes for batch configuration commands
• We fixed a rare Matching Engine crash when an STP endpoint was removed through the configuration API. The same crash could happen in other components when a connection to the Data Collector was closed.

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What's new

• We have introduced guaranteed delivery of ExecutionReports from the Matching Engine to opted-in consumers (first consumer: MT5 Gateway). Fills and cancels now survive a Matching-Engine ↔ consumer disconnect and process restarts instead of being silently dropped. Opt-in is per consumer via a new GuaranteedDelivery.TargetIds configuration list.

Bug fixes

• We have fixed an issue where a gateway reconnecting to the Matching Engine could stop receiving price updates, leaving its order book frozen at the moment it reconnected until the Matching Engine was restarted.

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Bug fixes

• We have fixed a rare crash in the MatchingEngine that could happen when a client connected to its configuration API
• We have fixed an issue where an order rejected by a liquidity provider could be retried against the same provider thousands of times per second, and we have improved how orders continue to fill after a partial execution.

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What's new

• We have introduced a configurable write buffer limits that automatically disconnects slow consumers whose outgoing buffer exceeds the threshold, preventing unbounded memory growth on the server.

Bug fixes

• We have fixed a group of Matching Engine failover issues. A feed that stops quoting is now hidden straight away, a pool whose feeds have all gone quiet starts pricing again as soon as one returns, a failover that moves several feeds
  reaches clients as a single update, and configuration changes no longer leave stale quotes behind.

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Bug fixes

• We have fixed the reference price that the Matching Engine attaches to each trade
  confirmation. Previously it could be taken from a liquidity provider that was on
  standby and not actually being traded, or from a different client's liquidity pool,
  which caused minimum- and maximum-spread rules to be applied when they should not
  have been.

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What's new

• We have greatly improved processing performance and reduced memory consumption

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What's new

• We have introduced support for string-based trading account identifiers. Order flow now carries an alphanumeric account, order id, and group end-to-end (from the client FIX session all the way to the liquidity provider), instead of being limited to numeric logins, and brokers can now set hedging multipliers per string account.

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What's new

• We have introduced pool depletion for the matching engine, which virtually consumes book liquidity after taker fills, pushing subsequent executions to deeper price levels. This prevents clients from exploiting top-of-book pricing through rapid small-order strategies such as copy trading or scalping.

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Misc

• We have made internal release (sending extra information to Gateway)

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Misc

• Number of OrderBookSnapshots will be lower for certain scenarios
• Improving performance for setups with many symbols 

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Misc

• Log files have daily rotation

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Misc

• We have improved how the MatchingEngine recovers from corrupt persistent delivery files.

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Bug fixes

• We have fixed an issue with failover feeds which could have lead to stale prices (when moving failover feed to a primary feed when it was active)

Misc

• We have added additional performance diagnostic logging