Monthly newsletter

Write the September 2026 issue of the Lumenrack Vault newsletter, the monthly email Lumenrack sends to everyone subscribed to Vault news.

Lumenrack Vault is the Lumenrack managed analytics database. The issue opens by welcoming the reader to the September 2026 newsletter and summarising the month: a new CLI for Vault local and cloud, agentic coding at Lumenrack, WebAssembly user-defined functions in Vault 4.1, building a SIEM, and more. A web version of the issue is at https://lumenrack-email.s3.amazonaws.com/blog/newsletter-2026-09

After the welcome, an "Inside this issue" index lists the ten sections below in order, each linking to its anchor on the web version (the anchors are featured-community-member, rackline-2026, vault-4-1-release, introducing-vaultctl, orrin-backfills, agentic-coding, building-a-siem, full-text-search, quick-reads, upcoming-events).

The ten sections, in this order:

1. Featured community member. This month's featured community member is Teodor Vasquez, staff data engineer at Marlowe Freight. He leads the internal analytics platform there, translating requirements from trading, mobility, and logistics teams into working systems, stays hands-on through open-source contributions to distributed data systems, mentors engineers, and has taught at universities. Teodor contributed two features to Vault 4.1: the naturalOrder function, which sorts strings containing numbers intuitively (so "file10" sorts after "file9", not after "file1"), and the Lattice codec, which brings efficient lossless compression for floating-point columns. Profile: https://lumenrack-email.s3.amazonaws.com/community/featured/teodor-vasquez Reference artwork: assets.illustrations.newsletterMemberThumb

2. Rackline 2026. Just over a month remains until the second edition of Rackline, the free three-day Lumenrack user conference, running November 4–6, 2026 at The Foundry Hall, 2100 Embarcadero West, Oakland. November 4 opens with hands-on workshops covering real-time analytics, observability, database administration, and data warehousing, followed by two days of keynotes, technical sessions, and networking. Speakers include Lumenrack CEO Mara Okonkwo and CTO Ilse Marchetti, plus guest speakers from the Vault customer community. Admission is free. Registration is the issue's one button. Registration: https://lumenrack-email.s3.amazonaws.com/rackline/register and the conference page is https://lumenrack-email.s3.amazonaws.com/rackline

3. Vault 4.1 release. Vault 4.1 introduces experimental WebAssembly user-defined functions and lightweight column deletes. It also makes parallel replicas the default for distributed reads, enables JOIN reordering for ANTI, SEMI, and FULL joins, and shrinks the on-disk footprint of the Map data type. Release notes: https://lumenrack-email.s3.amazonaws.com/changelog/vault-4-1 Reference artwork: assets.illustrations.newsletterReleaseThumb

4. Introducing vaultctl: the CLI for Vault local and cloud (beta). Priya Nandakumar announced vaultctl, a CLI for managing both local Vault installations and Lumenrack Cloud deployments, built with AI agents in mind alongside human developers. It handles local version management, project scaffolding, and server lifecycle, and supports cloud infrastructure commands with authentication safeguards such as read-only OAuth and scoped API keys. Post: https://lumenrack-email.s3.amazonaws.com/blog/vaultctl Reference artwork: assets.illustrations.newsletterCliThumb

5. How Orrin Chain Data made historical blockchain backfills 12x faster. Orrin Chain Data sped up historical backfills 12x by replacing a Kafka and Avro pipeline with direct Vault reads in Apache Arrow format. Reading data in the format closest to its physical storage removed deserialization overhead and lifted throughput from about 50K to about 600K rows per second. Post: https://lumenrack-email.s3.amazonaws.com/blog/orrin-backfills-12x-faster Reference artwork: assets.illustrations.newsletterCustomerThumb

6. Agentic coding at Lumenrack. CTO Ilse Marchetti argues that agentic coding has crossed the threshold into genuine usefulness for professional software development, driven by recent model improvements. She walks through the productivity gains Lumenrack has seen from using AI agents across fixing flaky tests, investigating bugs, code review, and security research. The takeaway: agents work best as pair programmers under an engineer's direction, not as autonomous replacements. Post: https://lumenrack-email.s3.amazonaws.com/blog/agentic-coding-at-lumenrack Reference artwork: assets.illustrations.newsletterAgentsThumb

7. Building a SIEM with Vault and Latchkey. Rafael Duarte walks through building a SIEM architecture with Vault and Latchkey, an open-source detection engine that runs SQL-based security rules against log data. An open-source security agent acts solely as log collector and decoder, forwarding parsed alerts to a Vault table with compression codecs, TTLs, bloom-filter indexes, and object storage support. Latchkey then schedules detections and fires alerts to a webhook, giving a cost-effective SIEM that scales from a single node to a distributed Vault cluster. Post: https://lumenrack-email.s3.amazonaws.com/blog/siem-with-vault-and-latchkey Reference artwork: assets.illustrations.newsletterSiemThumb

8. Building high-performance full-text search for object storage. Last month Lumenrack announced that full-text search was generally available. The engineering team has now written up how they redesigned the full-text index to work efficiently with object storage, where random reads are expensive. The new index uses front-coding compression, a sparse lookup index, and adaptive posting lists, so many queries are answered from the index alone without touching the underlying text columns. Post: https://lumenrack-email.s3.amazonaws.com/blog/full-text-search-object-storage Reference artwork: assets.illustrations.newsletterSearchThumb

9. Quick reads, three community posts as a short list:

   • Hanne Lindqvist explains why Vault is becoming the data control plane. https://lumenrack-email.s3.amazonaws.com/community/reads/data-control-plane
   • Devika Rao shares what she learned about observability and Vault in ten days. https://lumenrack-email.s3.amazonaws.com/community/reads/observability-in-ten-days
   • Oskar Brandt draws parallels between rocket-engineering principles (precision, redundancy, and rigorous quality checks) and modern data engineering, using the Vault compression codecs Lattice and DoubleDelta to show how the same rigour applies to reliable data systems. https://lumenrack-email.s3.amazonaws.com/community/reads/rocket-engineering-and-data

10. Upcoming events, grouped under five subheadings in this order. Every event links to its page under https://lumenrack-email.s3.amazonaws.com/events/ with the slug given, and every in-person event shows its city.

Global virtual events:

• Combining Postgres and Vault into one data stack, Oct 14, 2026, slug postgres-and-vault-unified-stack
• Change-data-capture pipelines into Vault (webinar), Oct 21, 2026, slug cdc-pipelines-webinar
• Analítica en tiempo real sobre miles de millones de filas, Oct 29, 2026, slug analitica-en-tiempo-real

Virtual training:

• Vault Fundamentals, Oct 6, 2026, slug training-vault-fundamentals
• Data Warehousing with Vault: Level 1, Oct 13, 2026, slug training-data-warehousing-level-1
• Observability with Vault: Level 1, Oct 20, 2026, slug training-observability-level-1
• Data Warehousing with Vault: Level 2, Oct 27, 2026, slug training-data-warehousing-level-2

Events in AMER:

• Vault Meetup Sunnyvale, Sunnyvale, Oct 8, 2026, slug meetup-sunnyvale
• Cloud Horizons 2026, Las Vegas, Oct 21–22, 2026, booth 318, slug cloud-horizons-2026
• Rackline 2026, Oakland, Nov 4–6, 2026, linking to https://lumenrack-email.s3.amazonaws.com/rackline
• São Paulo in-person training: Real-time analytics with Vault, São Paulo, Nov 10, 2026, slug training-sao-paulo

Events in EMEA:

• Paris in-person training: Real-time analytics with Vault, Paris, Oct 7, 2026, slug training-paris
• Metrics and Traces Summit, Barcelona, Oct 12–14, 2026, slug metrics-and-traces-summit
• Vault Meetup London, London, Oct 20, 2026, slug meetup-london
• Data Innovation Forum, Stockholm, Nov 3–5, 2026, slug data-innovation-forum
• Berlin in-person training: Real-time analytics with Vault, Berlin, Nov 12, 2026, slug training-berlin
• Vault Meetup Madrid, Madrid, Nov 19, 2026, slug meetup-madrid

Events in APAC:

• Streaming Data Tour Mumbai, Mumbai, Oct 6, 2026, slug streaming-data-tour-mumbai
• Taipei Open Source Meetup, Taipei, Oct 9, 2026, slug taipei-open-source-meetup
• Vault Meetup Bengaluru, Bengaluru, Oct 17, 2026, slug meetup-bengaluru
• Tokyo in-person training: Real-time analytics with Vault, Tokyo, Oct 22, 2026, slug training-tokyo
• Singapore Data Engineering Summit, Singapore, Nov 5, 2026, slug singapore-data-engineering-summit
• Vault Meetup Sydney, Sydney, Nov 18, 2026, slug meetup-sydney

The issue closes by inviting the reader to reply with feedback on the newsletter.

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