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Feldera: Real-Time Incremental View Maintenance for SQL
Company blog · feldera.com/blogdataprogramming
Feldera: Real-Time Incremental View Maintenance for SQL is the company blog at feldera.com, writing about data and programming. Since 2023, 21 different Hacker News readers have linked it 53 times, most often “Cutting down Rust compile times from 30 to 2 minutes with one thousand crates”. No feed was found, so read it on the site itself.
Too few sampled comments (16) to say how often HN recommends it.?
Why HN links it
HN readers link Feldera's engineering blog for posts on GitHub Actions pain, recursive SQL, Rust compile times, streaming storage and in-product profiling. Most comments cite these posts as sources for their own points.
Summarised by Claude from a sample of 16 HN comments that link here. Each comment is marked recommending, critical or neutral (citing without judging); how this works.
Incremental view maintenance for your lakehouse. Feldera keeps any SQL fresh in milliseconds. 10x the data, same 200ms. No batch jobs, no rewrites.
Most-linked posts?
- Cutting down Rust compile times from 30 to 2 minutes with one thousand crates6 people · 8 mentions · first linked 2025-04-15
- The Feldera Incremental Computation Engine3 people · 3 mentions · first linked 2024-10-25
- /3 people · 3 mentions · first linked 2024-10-20
- The Pain That Is GitHub Actions3 people · 3 mentions · first linked 2025-03-17
- The Babel Tower of SQL Dialects2 people · 2 mentions · first linked 2025-06-27
- /blog/recursive-sql-queries-in-feldera2 people · 2 mentions · first linked 2025-06-15
- RocksDB: Not a Good Choice for a High-Performance Streaming Platform2 people · 2 mentions · first linked 2024-07-25
What Hacker News says?
Definitely not a skill issue if you read the details in their post - https://www.feldera.com/blog/the-pain-that-is-github-actions - they're clearly very experienced with using GitHub Actions and have run into legitimate challenges due to the complexity of what they're using it for.
Comment linking /blog/the-pain-that-is-github-actions
on “The Pain That Is GitHub Actions”Submitted The Pain That Is GitHub Actions as a story · 704 points
HN discussionOh this very much reminds me of [feldera]( https://feldera.com ) — they do incremental loads and computations using some novel approaches (most of which i am too dumb to follow). Really nice folks too.
Comment linking /
on “Drasi: Microsoft's open source data processing platform for event-driven systems”Submitted Cutting down Rust compile times from 30 to 2 minutes with one thousand crates as a story · 143 points
HN discussionNot sure either. We added recursion to SQL in Feldera and it's Turing-complete: https://www.feldera.com/blog/recursive-sql-queries-in-felder...
Comment linking /blog/recursive-sql-queries-in-feldera
on “Datalog in Rust”Submitted Cutting Down Rust Compile Times with One Thousand Crates as a story · 13 points
HN discussionI struggle to understand the Clojure/Datomic dialect, but I agree generally. I recommend Percival for playing around with Datalog in a friendly notebook environment online: https://percival.ink/ Although there’s no “ANSI SQL” equivalent standard across Datalog implementations, once you get a hang of the core idea it’s not too hard to understand another Datalog. I started a Percival fork that compiles the Datalog to…
Comment linking /blog/recursive-sql-queries-in-feldera
on “Datalog in Rust”Submitted Solving Fine Grained Authorization with Incremental Computation as a story · 13 points
HN discussionThe Differential Datalog team founded Feldera: https://www.feldera.com/ They switched from differential Datalog to differential SQL, I think because they realized Datalog is a really tough sell.
Comment linking /
on “Datalog in Rust”Submitted RocksDB: Not a Good Choice for a High-Performance Streaming Platform as a story · 8 points
HN discussionRust has long compilation times because it doesn't prioritise compilation times. What does [0] have to do with the borrow checker? [0] https://www.feldera.com/blog/cutting-down-rust-compile-times...
Comment linking /blog/cutting-down-rust-compile-times-from-30-to-2-minutes-with-one-thousand-crates
on “Rust compiler performance”Submitted Feldera stream processing 6.2X Flink on Nexmark Benchmark as a story · 6 points
HN discussion> That doesn't sound likely. I would expect seconds unless something very odd is happing. And yet here we are. There are plenty of stories like this floating around of degenerate cases of small projects. Here's [0] one example with numbers and how they solved it. There are enough of these issues that by getting bogged down in "well technically it's not Rust's fault, it's LLVM's single threadedness causing the slowdo…
Comment linking /blog/cutting-down-rust-compile-times-from-30-to-2-minutes-with-one-thousand-crates
on “Rust compiler performance”Submitted Real-Time Feature Engineering as a story · 6 points
HN discussionHard agree. Practically all the bottlenecks we run into with Rust compilation have to do with the LLVM passes. The frontend doesn't even come close. (e.g. https://www.feldera.com/blog/cutting-down-rust-compile-times... )
Comment linking /blog/cutting-down-rust-compile-times-from-30-to-2-minutes-with-one-thousand-crates
on “Rust compiler performance”Submitted Making samply profiles more useful as a story · 4 points
HN discussionLLVM optimizations are the overwhelming majority of the compilation bottleneck for us over at Feldera. We blogged about some of the challenges we faced here: https://www.feldera.com/blog/cutting-down-rust-compile-times... We almost definitely need to build a JIT in the future to avoid this problem.
Comment linking /blog/cutting-down-rust-compile-times-from-30-to-2-minutes-with-one-thousand-crates
on “Rust compiler performance”Submitted The Babel Tower of SQL Dialects as a story · 4 points
HN discussionFeldera ( https://feldera.com | REMOTE (US) | Full-Time RELIABILITY AND PERFORMANCE ENGINEER: https://jobs.ashbyhq.com/feldera/709c14e4-1fa9-46b4-9ff8-078... - Strong background in systems engineering, performance testing, or site reliability engineering. - Fluency in Python and Linux fundamentals. Rust experience is a plus. - Experience with distributed systems and database concepts (consistency, fault tolerance, t…
Comment linking /
on “Ask HN: Who is hiring? (October 2025)”Submitted RocksDB: Not a Good Choice for a High-Performance Streaming Platform as a story · 4 points
HN discussionYour intuition is correct. Incremental computation is fundamentally a time-space tradeoff. Depending on the views you write, you might end up maintaining large amounts of state. We've written about it here: https://www.feldera.com/blog/streaming-needs-storage That said, Feldera has several features to keep state bounded even when computing on infinite streams. For example, we do automatic garbage collection (GC) whe…
Comment linking /blog/streaming-needs-storage
on “Feldera Incremental Compute Engine”Submitted The Pain That Is GitHub Actions as a story · 4 points
HN discussionThanks for the kind words! (Feldera's CEO here) - We evaluate top-k queries incrementally and the nesting shouldn't be a problem for the engine (or it'd be a bug). If you have an example of a query, we can try it out at our end. - Yes. It is internally consistent. We've verified with the experiment here: https://www.scattered-thoughts.net/writing/internal-consiste... . Our guarantee is that we always produce the sam…
Comment linking /blog/synchronous-streaming/
on “Feldera Incremental Compute Engine”Submitted SQL vs. DSL for Feature Engineering as a story · 4 points
HN discussionWe have our own formal model called DBSP: https://docs.feldera.com/papers It is indeed inspired by timely/differential, but is not exactly comparable to it. One nice property of DBSP is that the theory is very modular and allows adding new incremental operators with strong correctness guarantees, kind of LEGO brick for incremental computation. For example we have a fully incremental implementation of rolling aggrega…
Comment linking /blog/rolling-aggregates
on “Streaming joins are hard”Submitted How to Analyze Unbounded Time-Series Data Using Bounded State as a story · 4 points
HN discussionThe correct way to think about the problem is in terms of evaluating joins (or any other queries) over changing datasets. And for that you need an engine designed for *incremental* processing from the ground up: algorithms, data structures, the storage layer, and of course the underlying theory. If you don't have such an engine, you're doomed to build layer of hacks, and still fail to do it well. We've been building…
Comment linking /
on “Streaming joins are hard”Submitted RocksDB: Not a Good Choice for a High-Performance Streaming Platform as a story · 4 points
HN discussionA streaming join indeed requires an unbounded buffer in the most general case when inputs keep growing and any input record on one side of the join can match any record on the other side. However, it does not require inputs to be ordered. An incremental query engine such as Feldera or Materialize can handle out-of-order data and offer strong consistency guarantees (disclaimer: I am a developer of Feldera). In practi…
Comment linking /blog/asof-join
on “Streaming joins are hard”Submitted Nobody ever got fired for using a struct as a story · 3 points
HN discussion
