From ac75274283f6de8d0c99da18a0ac28f29a8797ed Mon Sep 17 00:00:00 2001
From: Antoine Pitrou <antoine@python.org>
Date: Tue, 28 Apr 2026 17:19:17 +0200
Subject: [PATCH] Add fundable project for Arrow run-end-encoding

---
 .../descriptions/RunEndEncodedInArrowCpp.md   | 50 +++++++++++++++++++
 src/components/fundable/projectsDetails.ts    | 13 +++++
 .../RunEndEncodedInApacheArrow/GetAQuote.tsx  |  9 ++++
 .../RunEndEncodedInApacheArrow/index.tsx      |  9 ++++
 4 files changed, 81 insertions(+)
 create mode 100644 src/components/fundable/descriptions/RunEndEncodedInArrowCpp.md
 create mode 100644 src/pages/fundable/RunEndEncodedInApacheArrow/GetAQuote.tsx
 create mode 100644 src/pages/fundable/RunEndEncodedInApacheArrow/index.tsx

diff --git a/src/components/fundable/descriptions/RunEndEncodedInArrowCpp.md b/src/components/fundable/descriptions/RunEndEncodedInArrowCpp.md
new file mode 100644
index 00000000..75b0eded
--- /dev/null
+++ b/src/components/fundable/descriptions/RunEndEncodedInArrowCpp.md
@@ -0,0 +1,50 @@
+#### Overview
+
+Apache Arrow is the universal columnar format and multi-language toolbox for fast data interchange and in-memory analytics.
+
+Run-End-Encoding is a composite Arrow datatype that efficiently represents data with many repeated values, such as timeseries.
+While basic support is present, Run-End-Encoding is not universally supported in all Arrow C++ components.
+
+We propose to finish implementing support for Run-End-Encoding in all components of Arrow C++:
+
+* cast kernels (including implicit run-end-encoding or decoding where applicable)
+
+* scalar kernels:
+    - all unary kernels (math, etc.)
+    - all binary kernels (arithmetic, comparisons, etc.)
+    - `coalesce`, `if_else`, `case_when`
+    - fix incorrect output in `is_null` and `true_unless_null`
+
+* vector kernels:
+    - cumulative aggregations (`cumulative_max`, `cumulative_sum`, etc.)
+    - `pairwise_diff`
+    - `filter`, `take`, `scatter`
+    - `fill_null_forward`, `fill_null_backward`
+    - `replace_with_mask`
+    - `indices_non_zero`
+    - `sort_indices`, `rank`, `rank_normal`, `rank_quantile`
+    - `partition_nth_indices`
+    - `select_k_unstable`
+    - `unique`, `value_counts`
+    - `winsorize`
+    - fix incorrect output in `drop_null`
+
+* aggregate kernels:
+    - `all`, `any`
+    - `count_distinct`
+    - `approximate_median`
+    - `sum`, `product`, `mean`, `mode`, `quantile`, `tdigest`
+    - `variance`, `stddev`, `skew`, `kurtosis`
+    - `first`, `last`, `min`, `max`
+    - `index`
+    - fix incorrect output in `count`
+
+* Parquet reader and writer
+
+* CSV reader
+
+* ORC reader and writer
+
+Funders can decide to fund the entire package, or choose the components they are interested in.
+
+##### Are you interested in this project? Either entirely or partially, contact us for more information on how to help us fund it.
diff --git a/src/components/fundable/projectsDetails.ts b/src/components/fundable/projectsDetails.ts
index 07568ddb..1f11b031 100644
--- a/src/components/fundable/projectsDetails.ts
+++ b/src/components/fundable/projectsDetails.ts
@@ -8,6 +8,7 @@ import MatrixOperationsInXtensorMD from "@site/src/components/fundable/descripti
 import BinaryViewInArrowCppMD from "@site/src/components/fundable/descriptions/BinaryViewInArrowCpp.md"
 import Decimal32InArrowCppMD from "@site/src/components/fundable/descriptions/Decimal32InArrowCpp.md"
 import Float16InArrowCppMD from "@site/src/components/fundable/descriptions/Float16InArrowCpp.md"
+import RunEndEncodedInArrowCppMD from "@site/src/components/fundable/descriptions/RunEndEncodedInArrowCpp.md"
 import ParquetNullOptimizationsMD from "@site/src/components/fundable/descriptions/ParquetNullOptimizations.md"
 
 export const fundableProjectsDetails = {
@@ -140,6 +141,18 @@ export const fundableProjectsDetails = {
             currentFundingPercentage: 0,
             repoLink: "https://github.com/apache/arrow"
         },
+        {
+            category: "Apache Arrow and Parquet",
+            title: "Complete Run-End-Encoded support in Arrow C++",
+            pageName: "RunEndEncodedInApacheArrow",
+            shortDescription: "Like dictionary encoding, run-end-encoding allows representing some kinds of data more efficiently.",
+            description: RunEndEncodedInArrowCppMD,
+            price: "TBD",
+            maxNbOfFunders: 4,
+            currentNbOfFunders: 0,
+            currentFundingPercentage: 0,
+            repoLink: "https://github.com/apache/arrow"
+        },
         {
             category: "Apache Arrow and Parquet",
             title: "Parquet reader optimizations",
diff --git a/src/pages/fundable/RunEndEncodedInApacheArrow/GetAQuote.tsx b/src/pages/fundable/RunEndEncodedInApacheArrow/GetAQuote.tsx
new file mode 100644
index 00000000..a945b598
--- /dev/null
+++ b/src/pages/fundable/RunEndEncodedInApacheArrow/GetAQuote.tsx
@@ -0,0 +1,9 @@
+import useDocusaurusContext from '@docusaurus/useDocusaurusContext';
+import GetAQuotePage from '@site/src/components/fundable/GetAQuotePage';
+
+export default function FundablePage() {
+    const { siteConfig } = useDocusaurusContext();
+    return (
+      <GetAQuotePage/>
+    );
+}
\ No newline at end of file
diff --git a/src/pages/fundable/RunEndEncodedInApacheArrow/index.tsx b/src/pages/fundable/RunEndEncodedInApacheArrow/index.tsx
new file mode 100644
index 00000000..876857af
--- /dev/null
+++ b/src/pages/fundable/RunEndEncodedInApacheArrow/index.tsx
@@ -0,0 +1,9 @@
+import useDocusaurusContext from '@docusaurus/useDocusaurusContext';
+import LargeProjectCardPage from '@site/src/components/fundable/LargeProjectCardPage';
+
+export default function FundablePage() {
+    const { siteConfig } = useDocusaurusContext();
+    return (
+       <LargeProjectCardPage/>
+    );
+}