diff --git a/.config/nextest.toml b/.config/nextest.toml
index 63a141f3773..eb99cf61619 100644
--- a/.config/nextest.toml
+++ b/.config/nextest.toml
@@ -1,6 +1,14 @@
 [profile.default]
 slow-timeout = { period = "30s", terminate-after = 5 }
 
+# The multi-GiB regression tests are `#[ignore]`d, so only the "Rust tests (linux-musl)" job
+# runs them. Each holds several GiB live, so they are held to one at a time and given far more
+# than the default time budget.
+[test-groups.slow-multi-gib]
+max-threads = 1
+
 [[profile.default.overrides]]
-filter = 'test(compress_large_int | fsst_compress_offsets_overflow_i32)'
+filter = 'test(build_views_offsets_overflow_i32) + test(compress_large_int) + test(fsst_compress_offsets_overflow_i32)'
+test-group = 'slow-multi-gib'
+slow-timeout = { period = "60s", terminate-after = 20 }
 priority = 100
diff --git a/.github/workflows/musl.yml b/.github/workflows/musl.yml
index c331dbc2859..43a181c9891 100644
--- a/.github/workflows/musl.yml
+++ b/.github/workflows/musl.yml
@@ -71,6 +71,26 @@ jobs:
             --exclude vortex-bench --exclude lance-bench --exclude datafusion-bench --exclude vortex-datafusion \
             --exclude compress-bench --exclude random-access-bench --exclude vortex-bench-server
 
+      # The multi-GiB regression tests are `#[ignore]`d, so every test job skips them by
+      # default and this step is the only place they run. This job is the one that covers
+      # every event: `Rust tests (linux-arm64)` is gated to the upstream repository and is
+      # skipped on pushes to develop, so gating them there would leave forks and develop
+      # untested. They are named explicitly rather than run with a bare `--run-ignored`,
+      # which would also un-ignore the CUDA tests that have no GPU here, and the cargo
+      # arguments match the step above so that nothing is rebuilt. The `slow-multi-gib`
+      # nextest test group keeps them from running concurrently, since each holds several
+      # GiB live.
+      - name: Run multi-GiB regression tests
+        shell: bash
+        run: |
+          cargo nextest run --cargo-profile ci --locked --workspace --no-fail-fast --run-ignored only \
+            --exclude vortex-cuda --exclude vortex-cub --exclude vortex-nvcomp \
+            --exclude gpu-scan-cli --exclude vortex-test-e2e-cuda --exclude vortex-python-cuda \
+            --exclude vortex-duckdb --exclude duckdb-bench --exclude vortex-sqllogictest \
+            --exclude vortex-bench --exclude lance-bench --exclude datafusion-bench --exclude vortex-datafusion \
+            --exclude compress-bench --exclude random-access-bench --exclude vortex-bench-server \
+            -E 'test(build_views_offsets_overflow_i32) + test(compress_large_int) + test(fsst_compress_offsets_overflow_i32)'
+
       - name: Alert incident.io
         if: failure() && github.event_name == 'push' && github.ref == 'refs/heads/develop'
         uses: ./.github/actions/alert-incident-io
diff --git a/.github/workflows/rust-instrumented.yml b/.github/workflows/rust-instrumented.yml
index de135445176..26055db907b 100644
--- a/.github/workflows/rust-instrumented.yml
+++ b/.github/workflows/rust-instrumented.yml
@@ -177,6 +177,7 @@ jobs:
       MSAN_SYMBOLIZER_PATH: "/usr/bin/llvm-symbolizer"
       TSAN_OPTIONS: "symbolize=1:suppressions=${{ github.workspace }}/vortex-ffi/tsan_suppressions.txt"
       TSAN_SYMBOLIZER_PATH: "/usr/bin/llvm-symbolizer"
+      # Compiles the multi-GiB tests out of the sanitizer build entirely.
       VORTEX_SKIP_SLOW_TESTS: "1"
       # -Cunsafe-allow-abi-mismatch=sanitizer: libraries like compiler_builtins
       # unset -Zsanitizer flag and we should allow that.
@@ -243,6 +244,7 @@ jobs:
       MSAN_SYMBOLIZER_PATH: "/usr/bin/llvm-symbolizer"
       TSAN_OPTIONS: "symbolize=1:suppressions=${{ github.workspace }}/vortex-ffi/tsan_suppressions.txt"
       TSAN_SYMBOLIZER_PATH: "/usr/bin/llvm-symbolizer"
+      # Compiles the multi-GiB tests out of the sanitizer build entirely.
       VORTEX_SKIP_SLOW_TESTS: "1"
       # -Cunsafe-allow-abi-mismatch=sanitizer: libraries like compiler_builtins
       # unset -Zsanitizer flag and we should allow that.
diff --git a/Cargo.toml b/Cargo.toml
index 389d624c98f..59c529e2cc4 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -441,3 +441,8 @@ incremental = false
 # This improved build times significantly for default common cases that we use locally
 [profile.dev.package.vortex-fastlanes]
 debug = false
+
+# FSST's compression kernel is hot enough that an unoptimized build dominates the runtime of the
+# multi-GiB `fsst_compress_offsets_overflow_i32` regression (106s -> 64s locally when optimized).
+[profile.ci.package.fsst-rs]
+opt-level = 3
diff --git a/encodings/fsst/src/compress.rs b/encodings/fsst/src/compress.rs
index 9df8f6989dd..a02e97dffb6 100644
--- a/encodings/fsst/src/compress.rs
+++ b/encodings/fsst/src/compress.rs
@@ -368,8 +368,22 @@ mod tests {
         assert!(!fsst_output_fits_in_i32_offsets(usize::MAX));
     }
 
+    /// The i64 codes-offsets path must build a valid array. Driving `compress_views::<i64>`
+    /// directly covers the branch on a three-string input, so day-to-day coverage of it does not
+    /// depend on the multi-GiB `tests::fsst_compress_offsets_overflow_i32`.
+    #[test]
+    fn codes_offsets_i64_path_roundtrips() -> VortexResult<()> {
+        let array = VarBinViewArray::from_iter_str(["hello", "world", "fsst encoded"]);
+        let mut ctx = array_session().create_execution_ctx();
+        let compressor = fsst_train_compressor(array.as_array(), &mut ctx)?;
+        let mask = array.validity()?.execute_mask(array.len(), &mut ctx)?;
+        let fsst = super::compress_views::<i64>(array.as_view(), &mask, &compressor, &mut ctx)?;
+        assert_eq!(fsst.codes().offsets().dtype().as_ptype(), PType::I64);
+        assert_eq!(fsst.len(), array.len());
+        Ok(())
+    }
+
     /// Small inputs fit the i32 bound, so `fsst_compress` must pick i32 offsets.
-    /// The i64 branch is covered by `tests::fsst_compress_offsets_overflow_i32`.
     #[test]
     fn codes_offsets_dtype_small_input_is_i32() -> VortexResult<()> {
         let array = VarBinViewArray::from_iter_str(["hello", "world", "fsst encoded"]);
diff --git a/encodings/fsst/src/tests.rs b/encodings/fsst/src/tests.rs
index 2b908a8997f..00019927370 100644
--- a/encodings/fsst/src/tests.rs
+++ b/encodings/fsst/src/tests.rs
@@ -126,8 +126,6 @@ fn test_fsst_array_ops() {
     assert_arrays_eq!(fsst_array, canonical_array, &mut ctx);
 }
 
-// TODO(someone): ideally CI would run this in release mode as well since debug builds make the
-// allocation and compression loop substantially slower.
 /// Regression for #7833: [`fsst_compress`] must accept inputs whose cumulative compressed
 /// bytes exceed [`i32::MAX`]. Before the fix, the compress path hardcoded
 /// [`VarBinBuilder<i32>`] for the FSST output and panicked in
@@ -141,17 +139,20 @@ fn test_fsst_array_ops() {
 /// is on the FSST output side. After the fix the test must succeed with the row count
 /// preserved.
 ///
-/// Allocates ~1.1 GiB for the input and ~2.1 GiB for the FSST output (~3.2 GiB total), so
-/// it is gated to CI runs and skipped when `VORTEX_SKIP_SLOW_TESTS` is set. To run it
-/// locally:
+/// Allocates ~1.1 GiB for the input and ~2.1 GiB for the FSST output (~3.2 GiB total), so it is
+/// ignored by default and run only by the "Rust tests (linux-musl)" CI job. Setting
+/// `VORTEX_SKIP_SLOW_TESTS` at build time drops it from the binary, which is how the sanitizer
+/// jobs avoid compiling it at all. To run it locally (release mode, since debug builds make the
+/// allocation and compression loop substantially slower):
 ///
 /// ```text
-/// CI=1 cargo test --release -p vortex-fsst fsst_compress_offsets
+/// cargo test --release -p vortex-fsst fsst_compress_offsets -- --ignored
 /// ```
 ///
 /// [`fsst_compress`]: crate::compress::fsst_compress
-#[test_with::env(CI)]
 #[test_with::no_env(VORTEX_SKIP_SLOW_TESTS)]
+#[test]
+#[ignore = "slow: allocates ~3.2 GiB, run by the \"Rust tests (linux-musl)\" CI job"]
 fn fsst_compress_offsets_overflow_i32() {
     const STRING_LEN: usize = 64 * 1024;
     // Escape coding doubles every byte, so ~1.06 GiB of input compresses to ~2.13 GiB,
diff --git a/vortex-array/src/arrays/varbinview/build_views.rs b/vortex-array/src/arrays/varbinview/build_views.rs
index 8a6a5a0530d..bf4a0179858 100644
--- a/vortex-array/src/arrays/varbinview/build_views.rs
+++ b/vortex-array/src/arrays/varbinview/build_views.rs
@@ -492,8 +492,6 @@ mod tests {
         build_views(0, MAX_BUFFER_LEN, bytes, &[31u32]);
     }
 
-    // TODO(someone): ideally CI would run this in release mode as well, since debug builds make the
-    // ~2.25 GiB allocation and fill loop substantially slower.
     /// Slow regression for the single-buffer fast-path guard. The fast path is only valid when the
     /// whole heap fits in one buffer (`bytes.len() <= max_buffer_len`); once the heap exceeds
     /// [`MAX_BUFFER_LEN`] (`i32::MAX`, ~2.0 GiB) `build_views` must roll the heap into multiple
@@ -506,15 +504,19 @@ mod tests {
     /// the fast path swallowed the whole heap, it would emit a single >2 GiB buffer with offsets past
     /// `i32::MAX`, which the buffer-count and buffer-size assertions catch.
     ///
-    /// Allocates ~2.25 GiB, so it is gated to CI and skipped when `VORTEX_SKIP_SLOW_TESTS` is set:
+    /// Allocates ~2.25 GiB, so it is ignored by default and run only by the "Rust tests
+    /// (linux-musl)" CI job. Setting `VORTEX_SKIP_SLOW_TESTS` at build time drops it from the
+    /// binary, which is how the sanitizer jobs avoid compiling it at all. To run it locally
+    /// (release mode, since debug builds make the allocation and fill loop substantially slower):
     ///
     /// ```text
-    /// CI=1 cargo test --release -p vortex-array build_views_offsets_overflow
+    /// cargo test --release -p vortex-array build_views_offsets_overflow -- --ignored
     /// ```
     ///
     /// [`MAX_BUFFER_LEN`]: super::MAX_BUFFER_LEN
-    #[test_with::env(CI)]
     #[test_with::no_env(VORTEX_SKIP_SLOW_TESTS)]
+    #[test]
+    #[ignore = "slow: allocates ~2.25 GiB, run by the \"Rust tests (linux-musl)\" CI job"]
     fn build_views_offsets_overflow_i32() {
         const STRING_LEN: usize = 64 * 1024;
         // Comfortably past MAX_BUFFER_LEN (`i32::MAX` ~= 2.0 GiB) so the heap must roll over.
diff --git a/vortex-btrblocks/src/schemes/integer/tests.rs b/vortex-btrblocks/src/schemes/integer/tests.rs
index a9ef24dc0e0..047a6582ca5 100644
--- a/vortex-btrblocks/src/schemes/integer/tests.rs
+++ b/vortex-btrblocks/src/schemes/integer/tests.rs
@@ -15,11 +15,13 @@ use vortex_array::arrays::Dict;
 use vortex_array::arrays::Masked;
 use vortex_array::arrays::PrimitiveArray;
 use vortex_array::assert_arrays_eq;
+use vortex_array::dtype::PType;
 use vortex_array::validity::Validity;
 use vortex_buffer::Buffer;
 use vortex_buffer::BufferMut;
 use vortex_buffer::buffer;
 use vortex_compressor::CascadingCompressor;
+use vortex_error::VortexExpect;
 use vortex_error::VortexResult;
 use vortex_fastlanes::RLE;
 use vortex_sequence::Sequence;
@@ -128,8 +130,16 @@ fn test_rle_compression() -> VortexResult<()> {
     Ok(())
 }
 
-#[test_with::env(CI)]
+/// Compresses 50M values, so it is ignored by default and run only by the "Rust tests
+/// (linux-musl)" CI job. Setting `VORTEX_SKIP_SLOW_TESTS` at build time drops it from the
+/// binary, which is how the sanitizer jobs avoid compiling it at all. To run it locally:
+///
+/// ```text
+/// cargo test --release -p vortex-btrblocks compress_large_int -- --ignored
+/// ```
 #[test_with::no_env(VORTEX_SKIP_SLOW_TESTS)]
+#[test]
+#[ignore = "slow: compresses 50M values, run by the \"Rust tests (linux-musl)\" CI job"]
 fn compress_large_int() -> VortexResult<()> {
     const NUM_LISTS: usize = 10_000;
     const ELEMENTS_PER_LIST: usize = 5_000;
@@ -146,3 +156,45 @@ fn compress_large_int() -> VortexResult<()> {
 
     Ok(())
 }
+
+/// The compressor picks ALP exponents from a sample, so values the sample did not represent must
+/// be stored as patches, indexed per chunk. This is the structure `compress_large_int` reaches
+/// only by scale; here the misfit values are placed deliberately, which also pins the
+/// `patch_chunk_offsets` width across the three magnitudes it is chosen from.
+#[rstest::rstest]
+#[case::sparse_patches(200_000, 1_000, PType::U8)]
+#[case::dense_patches(200_000, 100, PType::U16)]
+#[case::many_patches(1_000_000, 10, PType::U32)]
+fn alp_patches_are_chunk_indexed(
+    #[case] len: usize,
+    #[case] patch_every: usize,
+    #[case] chunk_offsets_ptype: PType,
+) -> VortexResult<()> {
+    let mut ctx = SESSION.create_execution_ctx();
+
+    // Whole numbers dominate, so the sampled exponents encode them exactly; the sprinkled values
+    // need more decimal digits than those exponents can represent and must be patched.
+    let values = (0..len)
+        .map(|i| {
+            if i % patch_every == patch_every - 1 {
+                i as f64 + 0.123_456_789_012_345
+            } else {
+                i as f64
+            }
+        })
+        .collect::<PrimitiveArray>()
+        .into_array();
+
+    let compressed = BtrBlocksCompressor::default().compress(&values, &mut ctx)?;
+
+    let offsets = compressed
+        .children_names()
+        .iter()
+        .position(|name| name == "patch_chunk_offsets")
+        .map(|idx| compressed.children()[idx].clone())
+        .vortex_expect("compressed array must carry chunk-indexed ALP patches");
+    assert_eq!(offsets.dtype().as_ptype(), chunk_offsets_ptype);
+
+    assert_arrays_eq!(compressed, values, &mut ctx);
+    Ok(())
+}