Delta-state CRDTs: indexed sequences with YATA

Kyle Mathews on Twitter / X

D2TS enables really powerful streaming joins, aggregations, etc. and will be powering a lot of Electric features in the future!This is an early preview but very cool tech. First Typescript implementation of Differential Dataflow afaik. https://t.co/i4qSJnVZWV— Kyle Mathews (@kylemathews) February 28, 2025

The CRDT Dictionary: A Field Guide to Conflict-Free Replicated Data Types - Ian Duncan

A comprehensive guide to CRDTs and their tradeoffs, from counters to sequences. Written in the spirit of the Typeclassopedia, exploring how different CRDTs solve the distributed consensus puzzle.

FlowLog - Efficient and Extensible Datalog | FlowLog

FlowLog: Efficient and Extensible Datalog via Incrementality

Engineering High-Performance Parsers with Data-Oriented Design

Notes from building Yuku: the AST is flat arrays of u32 indices instead of a pointer tree, and memory layout, allocation, strings, unicode, and serialization all follow from that one decision.

CompactLTJ: Space & Time Efficient Leapfrog Triejoin on Graph Databases

Leapfrog Triejoin (LTJ) is arguably the most practical and popular worst-case-optimal (wco) algorithm for solving basic graph patterns in graph databases. Its main drawback is that it needs the database triples (subject, predicate, object) represented as paths in a trie, for each of the six orders of subject, predicate, and object. The resulting blowup in space makes most systems disregard LTJ or implement it only partially, which makes their corresponding algorithms non-wco. In this paper we show that, by using compact data structures, it is possible to build an index that at the same time matches the query time performance of the fastest classic wco index, and uses a fraction of the space of non-wco indices (which are much slower). Concretely, we make use of compact tree representations to store functional tries using one bit per trie edge, instead of one pointer, and further reduce the space by storing partial tries. Our most compact variant uses 5–6 times less space than classic wco implementations and 2–3 times less than classic non-wco systems. At solving queries, it is on par with the fastest classic wco system, and 30–40 times faster than non-wco systems. We further incorporate improved query resolution strategies into CompactLTJ variants, which makes it considerably faster than classic wco systems as well, on queries that do not output too many results. Finally, we show how CompactLTJ can incorporate dynamism without altering its performance, even under very demanding update regimes. We leave a public fully-functional implementation of CompactLTJ that can be directly used by practitioners.

Delta Lenses over Inductive Types

Existing bidirectional languages are either state-based or operation-based, depending on whether they represent updates as mere states or as sequences of edit operations.In-between both worlds are delta-based frameworks, where updates are represented using alignment relationships between states.In this paper, we formalize delta lenses over inductive types using dependent type theory and develop a point-free delta lens language with an explicit separation of shape and data.In contrast with the already known issue of data alignment, we identify the new problem of shape alignment and solve it by lifting standard recursion patterns such as folds and unfolds to delta lenses that use alignment to infer meaningful shape updates.

Indexing Standard Site - AT Protocol

This guest post from Steve Simkins, creator of Sequoia and docs.surf, outlines the strategy he used to index standard.site records.

The Kaitchup Index: A Leaderboard for LLMs and Their Quantized Versions

Comparing formats like GGUF, GPTQ, and AWQ, with different bitwidths

Paul Copplestone - e/postgres on Twitter / X

we've released a CRDT extension for Postgres (experimental and open source)why? A CRDT is a special data type used for collaboration - think of a Google Doc. The changes are merged even as people are typing simultaneouslythese CRDTs are then serialized on a server and then… pic.twitter.com/WJDJlK733D— Paul Copplestone - e/postgres (@kiwicopple) November 21, 2025

Fast regex search: indexing text for agent tools · Cursor

How we're building indexes for regular expression search so agents can find text in large monorepos without the 15-second ripgrep waits.

Cosmik Lab Notes 003: Semble Updates - Discover, Collection Preview, Sorting, and more - Cosmik Labs

An overview of some recent enhancements to Semble (with a poll for next features!)

y-atproto - npmx

A [Yjs](https://yjs.dev/) CRDT provider that syncs documents over the [AT Protocol](https://atproto.com/). Documents are stored as ATProto records and real-time updates are delivered via [Jetstream](https://github.com/bluesky-social/jetstream).

Homomorphically Encrypting CRDTs | jakelazaroff.com

Homomorphic encryption allows a computer to run programs on encrypted data. Learn how homomorphic encryption works through interactive examples, build a homomorphically encrypted CRDT and see whether it has promise for local-first software.

A Conflict-Free Replicated JSON Datatype

Many applications model their data in a general-purpose storage format such as JSON. This data structure is modified by the application as a result of user input. Such modifications are well understood if performed sequentially on a single copy of the data, but if the data is replicated and modified concurrently on multiple devices, it is unclear what the semantics should be. In this paper we present an algorithm and formal semantics for a JSON data structure that automatically resolves concurrent modifications such that no updates are lost, and such that all replicas converge towards the same state (a conflict-free replicated datatype or CRDT). It supports arbitrarily nested list and map types, which can be modified by insertion, deletion and assignment. The algorithm performs all merging client-side and does not depend on ordering guarantees from the network, making it suitable for deployment on mobile devices with poor network connectivity, in peer-to-peer networks, and in messaging systems with end-to-end encryption.

Stream Processing: Continuous Processing of Data Streams

Explore the Stream Processing design pattern for continuous asynchronous data flow, enhancing real-time data processing capabilities in enterprise applications using Clojure and leveraging functional programming principles.

About CRDTs • Conflict-free Replicated Data Types

Resources and community around CRDT technology — papers, blog posts, code and more.