--- title: StreamFusion Supports Parquet Writing! | Personal... description: A solo developer shares a weekly progress update on StreamFusion, a Rust-based stream processing accelerator for Apache Flink. Highlights include shipping... canonical: https://daily.dev/posts/streamfusion-supports-parquet-writing-personal-projects-with-ex-google-swe-ep-38-lmlyh5wx0 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: StreamFusion Supports Parquet Writing! | Personal Projects With Ex-Google SWE, Ep 38 | daily.dev og:description: A solo developer shares a weekly progress update on StreamFusion, a Rust-based stream processing accelerator for Apache Flink. Highlights include shipping... og:url: https://daily.dev/posts/streamfusion-supports-parquet-writing-personal-projects-with-ex-google-swe-ep-38-lmlyh5wx0 og:image: https://api.daily.dev/og/posts/LMlYh5wX0.png og:image:alt: StreamFusion Supports Parquet Writing! | Personal Projects With Ex-Google SWE, Ep 38 og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # StreamFusion Supports Parquet Writing! | Personal Projects With Ex-Google SWE, Ep 38 **[Jordan has no life](https://daily.dev/sources/jordan-has-no-life)** · 16 min read · 2 upvotes · 0 comments ## Summary A solo developer shares a weekly progress update on StreamFusion, a Rust-based stream processing accelerator for Apache Flink. Highlights include shipping experimental Parquet writer support that flushes column chunks to reduce memory footprint, simplifying the Kafka connector after realizing a fully native Rust implementation wasn't worth the added complexity, exploring Apache Fluss for columnar message brokering, rewriting the protobuf serialization layer to use code-generated deserializers, and starting work on a Delta Lake sink. The developer also recounts an AI coding assistant hallucinating and forking a connector's internals during unsupervised work, prompting plans to add guardrails via unit tests. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### Why did StreamFusion drop its native Rust Kafka client in favor of using the JVM Kafka client with Java-to-Rust data copying? Profiling showed that copying bytes between the Java heap and Rust off-heap memory was not the actual bottleneck in the stream processing pipeline, and a native Rust Kafka client only offered a few extra percentage points of performance while adding huge complexity around consumer/producer configuration parity, Kerberos, SSL, and other security handshake protocols. For an early-stage, single-maintainer project, that complexity wasn't worth the marginal gain. _Track pragmatic tradeoffs like this Rust versus JVM Kafka client decision on daily.dev while building your own streaming pipelines._ ### How does a Rust-based Parquet writer reduce memory footprint compared to Flink's stock Java Parquet writer? Flink's standard Java Parquet writer flushes columns one column chunk at a time, while a Rust implementation using lower-level Parquet writing APIs can flush each column chunk to disk as soon as it's fully encoded within a row group, rather than waiting for the entire row group to be buffered in memory. This lowers peak memory usage, which matters for a system designed to also reduce memory footprint alongside CPU cost. _Compare memory-conscious Parquet writer designs on daily.dev when optimizing your own streaming data pipelines._ ### Why is Apache Fluss's Flink connector inefficient for column-oriented streaming systems? Fluss stores data internally as Arrow rows, which allows efficient column projection pruning, but its Flink connector converts that data back to row-by-row format before handing it off, even though consuming systems designed around column batches would prefer to receive Arrow batches directly. Work is underway to expose Arrow-batch reads for both append-only and primary-key tables to avoid this unnecessary row conversion. _Follow emerging streaming broker tradeoffs like this on daily.dev when evaluating Fluss or similar systems for your architecture._ --- Tags: [#rust](https://daily.dev/tags/rust), [#big-data](https://daily.dev/tags/big-data), [#apache-kafka](https://daily.dev/tags/apache-kafka), [#apache-flink](https://daily.dev/tags/apache-flink) [View this post on daily.dev](https://daily.dev/posts/streamfusion-supports-parquet-writing-personal-projects-with-ex-google-swe-ep-38-lmlyh5wx0) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"StreamFusion Supports Parquet Writing! | Personal Projects With Ex-Google SWE, Ep 38","url":"https://daily.dev/posts/streamfusion-supports-parquet-writing-personal-projects-with-ex-google-swe-ep-38-lmlyh5wx0","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/streamfusion-supports-parquet-writing-personal-projects-with-ex-google-swe-ep-38-lmlyh5wx0"},"datePublished":"2026-08-22T16:24:26.329Z","dateModified":"2026-09-14T07:43:51.182Z","description":"A solo developer shares a weekly progress update on StreamFusion, a Rust-based stream processing accelerator for Apache Flink. 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