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ArcadeDB 26.7.1: Raft Hardening, OpenTelemetry Tracing, BM25 & GQL

Luca Garulli· · 5 min read ·
Multi-Model High Availability Observability Security Graph Database Release
ArcadeDB 26.7.1 Release

We’re pleased to announce ArcadeDB 26.7.1, a large stability, resilience, and security release with 420+ commits resolving 238 issues. Where 26.6.1 added encrypted HA clusters and a durability hardening pass, 26.7.1 goes deeper into cluster resilience: the Raft engine now degrades gracefully instead of halting, diverged followers heal themselves, and the whole system is far easier to observe in production thanks to OpenTelemetry distributed tracing. On top of that come native BM25 full-text scoring, ISO GQL standards alignment, and another broad security sweep.

Major Highlights

Raft & High Availability Hardening

The headline of this release is resilience. A cluster should survive a bad entry, a network blip, or a diverged replica without operator intervention:

  • A failed apply on one database no longer halts the entire node. The affected database is put into per-database quarantine while every other database on the node keeps serving traffic.
  • Diverged followers can now self-recover back to the leader’s state instead of getting stuck.
  • Snapshot integrity is strengthened with fsync on write and manifest verification, so a follower never installs a truncated or corrupt snapshot.
  • Membership changes are applied as atomic deltas under quorum protection, closing the classic split-brain and lost-quorum windows.
  • Silent write loss on replication timeouts has been eliminated: a write that cannot be safely replicated is reported, not dropped.
  • TRUNCATE TYPE and TRUNCATE BUCKET are now HA-safe, follower index correlation is fixed by stable peer-id, and a stalled replica stuck at matchIndex=-1 now auto-recovers.

These are the fixes you feel in production during the unhappy path, not in a benchmark.

OpenTelemetry Distributed Tracing & Structured Logging

Observability is now first-class. A new OpenTelemetry module provides end-to-end distributed tracing with optional OTLP export, so you can follow a request across the wire protocols, the query engine, and the storage layer in your existing tracing backend. Alongside it:

  • Structured JSON logging with per-request correlation IDs, so a single request is trivial to reconstruct across logs and traces.
  • Enhanced metrics with RED timers (Rate, Errors, Duration) and engine gauges.

Native BM25 Full-Text Scoring

Full-text search now ships a native BM25 scoring implementation with field boosts and caret (^) boost syntax, so relevance ranking is tunable per field. EXPLAIN and PROFILE now cover search operations too, making it easy to see how a full-text query is planned and executed.

ISO GQL Standards Alignment

ArcadeDB continues moving toward the ISO GQL graph query standard:

  • Session management statements: SESSION SET / SESSION RESET / SESSION CLOSE.
  • Transaction control statements: START TRANSACTION / COMMIT / ROLLBACK.
  • Strict numeric types for standards-compliant arithmetic and comparisons.

Security Hardening

Another broad security sweep tightens the defaults for multi-tenant and internet-facing deployments:

  • Polyglot scripting now requires administrative privileges.
  • Centralized gRPC authorization enforcement across all endpoints.
  • Additional path-traversal protection hardening.
  • DoS bounding on gRPC result materialization.
  • Cluster-management endpoints are now restricted to root access.

Major Fixes

Vector Engine

  • New import/interop formats: MATLAB, MATLAB_COLUMN, JULIA, and NUMPY.
  • New helper functions: asVector(), asSparse(), and vectorDequantizeBinary.
  • Improved RRF (Reciprocal Rank Fusion) array input handling.

MongoDB Protocol

  • Added update, delete, and createIndexes commands.
  • SASL PLAIN authentication support.
  • Improved find command data handling.

Kubernetes Operations

  • Health probe endpoints for liveness, readiness, and startup.
  • Auto-acquire capability for databases the node has not seen yet.
  • StatefulSet scale-up support beyond a static peer list.

SQL & Queries

  • Map/collection key removal now persists correctly in UPDATE.
  • Improved index selection for composite-key queries.
  • Three-valued logic for NULL operands in IN / NOT IN.
  • Correct mixed-type numeric handling in GROUP BY and aggregation functions.

Storage & Recovery

  • Schema recovery from the backup file when the primary schema is corrupted.
  • Corrupt hash-index detection and recovery.
  • Time-series negative-timestamp alignment fixes.
  • Page I/O locking improvements.

Wire Protocols

  • gRPC: InsertStream now terminates correctly after a commit failure.
  • DATETIME precision is preserved across microsecond/nanosecond formats.
  • OpenCypher now tolerates dangling edges.
  • Improved client-side nested type hydration.

Dependencies

Notable upgrades include Netty 4.2.15, Lucene 10.5.0, OpenTelemetry BOM 1.63.0, Jackson Databind 2.22.0, and JVector 4.0.0-rc.8, plus the usual round of Studio frontend, e2e harness, and CI updates.

Getting Started with 26.7.1

Docker

docker pull arcadedata/arcadedb:26.7.1

Visit our Docker Hub repository for more information.

Maven

<dependency>
    <groupId>com.arcadedb</groupId>
    <artifactId>arcadedb-engine</artifactId>
    <version>26.7.1</version>
</dependency>

All artifacts are available on Maven Central.

Documentation

For detailed information on features and usage, refer to our comprehensive documentation.

Compatibility Note

This release maintains 100% compatibility with previous database formats, meaning no export/import is required when upgrading. As always, we recommend creating a database backup before upgrading.

Download ArcadeDB 26.7.1 now: GitHub Releases

Thanks to everyone in the community who reported issues, opened PRs, and helped shape this release.

Luca Garulli ArcadeDB Founder