OxideLake
A GPU-accelerated, Arrow-native distributed analytical query engine and columnar lakehouse, written in Rust.
Status: v1 complete. The default build is pure CPU and the whole gate is green on Linux x86_64 and macOS arm64; the Metal backend executes for real on Apple silicon (conformance-tested against stock DataFusion on an M4 Pro); the CUDA backend compiles and lints with no CUDA installed but has not yet run on a CUDA machine — see STATUS.md for the precise verification matrix. The specification the engine was built to is docs/SPEC.md.
Install
Both give you the oxide, oxide-scheduler and oxide-worker binaries.
The Homebrew formula is generated by the release itself from the archives'
checksums, so it never describes a build that did not happen.
Or download a static archive for Linux (x86_64, aarch64, musl) or macOS
(Apple silicon, Intel) from the latest release,
verify it against the .sha256 beside it, and put the three binaries on your
PATH. Using the engine as a library is cargo add oxidelake-api.
What OxideLake is
OxideLake runs the same plans in two modes over the Apache Arrow columnar memory model:
- Embedded mode (DuckDB-like) — in-process DataFusion; operators exchange
Arc<RecordBatch>over bounded async channels with no serialization. - Cluster mode (Spark-like) — Apache DataFusion Ballista schedules stages across executors and streams shuffle partitions over Arrow Flight; OxideLake supplies the GPU operators, the placement rule and the plan codec that ships them to executors.
Acceleration backends: CPU (always available, the correctness reference), NVIDIA CUDA (opt-in feature, NVRTC-JIT at runtime), Apple Metal on unified memory (opt-in, macOS only, MSL compiled at runtime).
The differentiator is the operator layer: GpuFilterExec (fused filter + projection), GpuHashJoinExec, GpuAggregateExec and GpuVectorDistanceExec are DataFusion ExecutionPlans with their own CUDA and Metal kernels behind one object-safe hardware abstraction. A placement rule rewrites eligible plan nodes for the target backend — EXPLAIN shows GpuFilterExec[metal] — and every operator still selects the real local backend at execution time and falls back per batch to the CPU reference, which is what keeps a heterogeneous cluster correct. Storage is Parquet pruned by DataFusion's statistics, page index and Bloom filters, with Arrow IPC for zero-decode spill and caches.
Quickstart
Everything below runs as written (Rust 1.98 via rust-toolchain.toml; the workspace builds on 1.94.1 and up — or just make quickstart):
# 1M-row demo table: Parquet with Bloom filters on id and k, page statistics on
# embedded SQL over it
# vector search: l2_distance / cosine_distance are built-in SQL UDFs
# what the plan looks like for a GPU cluster: placement tags without needing the GPU
# the terminal dashboard over a real query: plan DAG, per-operator telemetry, column profiles
In-database inference (optional, --features predict)
Score a row against a trained model without leaving SQL. Off by default; it pulls in a tensor library.
# an oxmera Sequential/Linear model saved with safetensors
+----+--------------------------+
| id | logits |
+----+--------------------------+
| 0 | [-31.006792, 3.9050333] |
| 1 | [7.2003703, -4.237343] |
+----+--------------------------+
It composes with everything else — including the vector search that was already here, which is the point: OxideLake could find the nearest rows and could not score them.
The model file is read for its architecture, not just its weights: predict
rebuilds an oxmera::nn::Sequential of Linear layers from the 0.weight,
1.weight, … naming, with ReLU between them. That assumption, the CPU-only
execution, and why this is a UDF rather than an operator are recorded in
ADR-0015.
--target cpu|cuda|metal picks the placement target; execution always uses the hardware that is present (operators planned for an absent GPU take the per-batch CPU path — exactly what cluster executors do with a scheduler's plan).
Cluster mode
# OXIDE_CLUSTER_BACKEND declares the cluster's placement capability (default: cpu, no rewrites)
OXIDE_CLUSTER_BACKEND=cuda &
&
The end-to-end test in crates/oxidelake-runtime/tests/cli.rs spawns exactly this topology on ephemeral ports and asserts the cluster output is byte-identical to embedded mode.
DataFrame API
use *;
let session = local?;
session.register_parquet.await?;
let nearest = session
.table.await?
.filter?
.vector_distance?
.sort?
.limit?
.collect.await?;
The fluent verbs build ordinary DataFusion plans, so the placement rule lowers them the same way it lowers SQL — .vector_distance(…) plans GpuVectorDistanceExec[metal] on a Metal target.
GPU backends
# CUDA: compiles and lints with no CUDA installed (cudarc dynamic loading + NVRTC)
# Metal (macOS): the conformance suite executes on the device
# On a CUDA machine (not yet run anywhere — reports welcome):
OXIDE_BACKEND=cuda
Repository map
| Path | Purpose |
|---|---|
crates/oxidelake-core |
EngineError, BackendKind, operator parameter types, TelemetryHub |
crates/oxidelake-memory |
64/128-byte-aligned buffers, pinned/UMA allocators, 3-tier SpillManager, Arrow IPC codec |
crates/oxidelake-device |
object-safe GpuBackend; CPU reference, CUDA (NVRTC) and Metal (MSL) backends; HardwareDetector |
crates/oxidelake-compute |
the four Gpu*Exec operators, per-batch CPU fallback, l2_distance/cosine_distance UDFs, conformance suite |
crates/oxidelake-storage |
Parquet writer/pruning config with proofs, Arrow IPC spill files, io_uring ObjectStore (Linux), gen-data generator |
crates/oxidelake-planner |
HardwarePlacementRule (+ vector-distance lowering before projection pushdown), OxidePhysicalCodec |
crates/oxidelake-runtime |
OxideSession (embedded + Ballista cluster), scheduler/worker wrappers, the oxide CLI, dashboard builder |
crates/oxidelake-tui |
ratatui dashboard, TestBackend snapshots and termlens PTY tests |
crates/oxidelake-api |
OxideFrame fluent DataFrame API and prelude |
crates/oxidelake-device/kernels/ |
CUDA C (.cu, NVRTC at runtime) and MSL (.metal, newLibraryWithSource) sources — inside the device crate so the published crate is self-contained (include_str! cannot reach outside a crate's directory at publish time; ADR-0016) |
docs/ |
roadmap · architecture · dependencies · verification · ADRs |
docs/SPEC.md |
The executable spec the build agent executed, phase by phase |
STATUS.md |
What is done, how it was verified, what was deferred — the honesty ledger |
Makefile · deny.toml |
make gate and friends; supply-chain policy for cargo deny |
Verification
Every change lands behind required-green and commit-policy. make gate
runs formatting, feature-specific Clippy, the test suites, all-feature rustdoc,
dependency-coherence and supply-chain checks, plus release and CI script tests.
CI separates the Linux feature tests and checks the
MSRV; macOS runs Metal and PTY tests and executes conformance when a Metal
device exists. Dependency caching reuses compilation while tests still run;
release CI retains a clean full gate. Known documentation-only changes may
skip Rust jobs under the tested verification policy.
The honesty rule applies throughout: nothing is claimed as working unless it
ran; GPU paths that only compiled are recorded as exactly that in
STATUS.md. The 2026-09-02 security and performance audit, with
every finding's status, is in docs/audit-2026-09-02.md.
Contributing
See CONTRIBUTING.md for the workflow (make help lists every target), SECURITY.md for the trust model and how to report vulnerabilities, and CHANGELOG.md for what changed.
License
Apache-2.0 — see LICENSE.