Penca – branchable, versioned OLTP+OLAP on one open copy of your data

In plain words

Penca is an open-source database that combines transactional and analytical capabilities on a single copy of data stored in object storage. It uses PostgreSQL for writes, automatically flushes committed data to columnar files, and queries both layers using a DataFusion-based engine. The system includes built-in data versioning and auditability features, enabling audit trails, point-in-time queries, and data recovery. It is designed for developers and organizations seeking an open alternative to commercial LTAP solutions.

written from the facts on this page · September 2026

From the sources

A version-controlled lakebase for the next generation of AI applications. - penca-io/penca

In the maker’s words, at launch

Hi HN! This is an early proof of concept of a branchable, versioned OLTP + OLAP database that runs on a single, open copy of your data in object storage. If you are familiar with Databricks' LTAP (https://www.databricks.com/company/newsroom/press-releases/d...) announcement from June…

• 
  I open-sourced the in-memory PostgreSQL I built at work for E2E tests2024 · github.com · ▲379

  In-memory Postgres for unit/E2E tests. Contribute to hexclave/pgmock development by creating an account on GitHub.

• 
  BemiDB – Postgres read replica optimized for analytics2024 · github.com · ▲209

  Hi HN! We're Evgeny and Arjun, and we’re building a better way to do analytics with Postgres. We love Postgres for its simplicity, power, and rich ecosystem. But engineers have to still get bogged down with heavyweight and expensive OLAP systems when connecting an analytics data stack. Postgres is amazing at OLTP queries, but not for OLAP queries (large data scans and aggregations). Even in this case, we’ve still heard from countless scaling startups that they still try to use only a read replica to run analytics workloads since they don’t want to deal with the data engineering complexity of…

• 
  Outerbase2023 · ▲295

  The interface for your database

• 
  Omni – Open-source workplace search and chat, built on PostgresMar 2026 · github.com · ▲177

  Hey HN! Over the past few months, I've been working on building Omni - a workplace search and chat platform that connects to apps like Google Drive/Gmail, Slack, Confluence, etc. Essentially an open-source alternative to Glean, fully self-hosted. I noticed that some orgs find Glean to be expensive and not very extensible. I wanted to build something that small to mid-size teams could run themselves, so I decided to build it all on Postgres (ParadeDB to be precise) and pgvector. No Elasticsearch, or dedicated vector databases. I figured Postgres is more than capable of handling the level…

• 
  ScratchDB – Open-Source Snowflake on ClickHouse2023 · github.com · ▲261

  Hello! For the past year I’ve been working on a fully-managed data warehouse built on Clickhouse. I built this because I was frustrated with how much work was required to run an OLAP database in prod: re-writing my app to do batch inserts, managing clusters and needing to look up special CREATE TABLE syntax every time I made a change. I found pricing for other warehouses confusing (what is a “credit” exactly?) and worried about getting capacity-planning wrong. I was previously building accounting software for firms with millions of transactions. I desperately needed to move from Postgres to…

• 
  HelixDBFeb 2026 · helix-db.com · ▲105

  An open-source OLTP graph-vector database built in Rust.

• 
  Run full iOS 16.5 firmware on Android Devices▲516

  Contribute to oosexgang/hackios-xnu-kernel development by creating an account on GitHub.

  Dev tools · 2d ago · github.com

• 
  /dev/null▲492

  a social network for devs

  Dev tools · 5d ago · dev-null.sh

• 
  Whiteboard (YC W26) – an open-source IDE for thoughtful software design▲423

  open-source IDE for thoughtful software design. Contribute to devdotfast/whiteboard development by creating an account on GitHub.

  Dev tools · 29d ago · github.com

• 
  Reladraw – A diagram language where you decide where to place things▲411

  Contribute to reladraw/reladraw development by creating an account on GitHub.

  Dev tools · 27d ago · github.com

• 
  OpenBot▲362

  Grok Bot alternative: free, local, open-source, multiplayer

  Dev tools · 25d ago · openbot.run

• 
  Talanoa▲346

  Hi HN, I’m a fullstack developer, and honestly, I’ve lost count of how many side projects I’ve worked on over the years. But one idea kept coming back to me: a different kind of email client. It first came to me in 2014: “What if we could handle emails more like conversations?” Every year, I’d revisit this concept in my “Build Notes.” Ten years later, no one had built exactly what I had in mind — so I finally decided to do it myself. That’s how Talanoa was born. I wanted something focused on people, not timelines. I was tired of marking messages as unread just to remember to reply later, or…

  Dev tools · 22d ago · talanoa.email

• IR
  I replaced a $120k bowling center system with $1,600 in ESP32s▲2,935

  I might be the only SRE on Earth with his own bowling center. It's a more in-depth gig than you'd think. My family and I bought an abandoned 8-lane bowling center in the rural mid-west. In our small town there weren't many recreation options for families. You've heard of a food desert? This is an R&R desert. It had been abandoned for a good reason. The roof leaks, the electrical system was constantly surging, and my 70-year-old bowling equipment (still) doesn't work perfectly. The system that keeps your score is particularly interesting to me. It's the thing you watch during your game, but…

  Life & fun · Jul 2026

• 
  Elevators▲1,680

  How elevators push your buttons

  Life & fun · Jul 2026 · john.fun

• 
  18 Words▲1,160

  Play 18 Words, the free daily word puzzle. The official home is 18words.com. Tap Play now to open today

  Life & fun · Jul 2026 · 18words.com

• BA
  Bento - An entire PowerPoint in one HTML file (edit+view+data+collab)▲1,033

  Over the past few months, our team has been building more and more slidedecks using web frontend technologies with coding harnesses like Claude Code, but a common complaint is to make even small edits we need to edit the code either manually or via the harness. To avoid this loop, I ended up creating Bento, a single HTML file with everything you need in a slide tool including animations and shared editing. There's no install or cloud login, everything works offline. The default deck is around 560 KB and it doesn't need to fetch anything once you got it. Open it in a browser and then you can…

  Dev tools · Jul 2026 · bento.page

• 
  Getting GLM 5.2 running on my slow computer▲937

  A few days ago I found myself trying out GLM 5.2 and was really positively impressed. The capabilities and security I was getting from this LLM are similar to those I've gotten from models like Claude or GPT, and this really surprised me. But then I thought, "I wonder how it would work on a normal computer like mine," and above all, "I wonder if it would work without going into OOM on a computer like mine." So I started working with the help of agents to test this possibility. I started converting the model to int4, understanding MTP usage, and if possible implementing DSA for long context.…

  AI · Jul 2026 · github.com

• 
  OpenSEO▲928

  Hello! For the last 2 months, I've been building OpenSEO. It's a user friendly UI wrapping the DataForSEO API which has high quality SEO data for keywords, backlinks, AI SEO and competitor research. Instead of paying $100+ per month, you buy DataForSEO credits and pay only for usage. The coolest thing about the project so far has been hearing about what people are building on top of it. People are using coding agents to quickly integrate with Google Search Console, Google Ads and building their own AI SEO and reporting features. Many were already building their own custom solutions around…

  Dev tools · Jul 2026 · openseo.so