Cudf Query Engine Builder
NVIDIAOfficialCreated by Joe SackDistributed by NVIDIA
- Skill
- Workflow
- Software development
- Apache-2.0
- Medium risk
- Has scripts
AutoGineer summary
Written by AutoGineer from the skill’s own files, not by the author
This skill provides a structured workflow for query-engine engineers to integrate cuDF into their existing systems. It focuses on building a functional, single-GPU proof of concept (POC) that demonstrates native execution, correct buffer management, and proper asynchronous cleanup. The process emphasizes maintaining clear boundaries between the engine's orchestration responsibilities and cuDF's device-wide algorithms, ensuring that memory ownership, lifetime management, and producer-consumer dependencies are handled safely.
What it does
- Maps query engine semantics to version-matched cuDF APIs.
- Defines buffer ownership, lifetime, and release strategies for GPU data.
- Implements adapter glue code to bridge the engine and libcudf or cuDF Java.
- Establishes correct asynchronous execution patterns and completion synchronization.
- Validates POC correctness against CPU-based reference implementations.
- Provides a framework for reporting native execution evidence and identifying blockers.
When to use it
- When you need to integrate cuDF into a query engine for the first time.
- When developing a new native adapter for libcudf C++ or cuDF Java.
- When you need to resolve buffer ownership or asynchronous cleanup issues in an existing integration.
- When you need to verify that a query engine is correctly offloading work to a single GPU.
Advantages
- Ensures safe memory management and exception handling in asynchronous GPU workflows.
- Maintains separation of concerns between engine orchestration and cuDF algorithms.
- Provides a clear path for validating native execution versus CPU simulations.
- Reduces integration risks by focusing on incremental, verifiable POCs.
Usage examples
- “Build a POC for a single-GPU filter operator in our C++ query engine using libcudf.”
- The agent will guide you through mapping the filter semantics to cuDF, implementing the adapter glue, managing the buffer ownership, and verifying the result against your CPU reference implementation.
- “How do I safely handle buffer cleanup in my cuDF adapter when an asynchronous call might throw?”
- The agent will provide a pattern for retaining owners outside of throwing scopes and establishing completion before releasing resources, as detailed in the asynchronous cleanup guidelines.
Install
Download the skill as a ZIP:
https://autogineer.com/agent-skills/nvidia/cudf-query-engine-builder/downloadUnzip it into the cross-client skills folder of your project:
mkdir -p .agents/skills && unzip cudf-query-engine-builder.zip -d .agents/skills
Documentation by Joe Sack
cuDF query-engine POC builder
Outcome and scope
Build the first native cuDF proof of concept in the target engine for a query-engine engineer. Produce working target-engine code, a runnable single-GPU program, and a correctness result, not only advice.
The POC may cover one operator, a sequence of operators, or a query selected for the POC. Do not reduce it to one operator by default. If a smaller increment is needed for feasibility or safe implementation, explain why and preserve the path to the requested POC.
For a request limited to an initial adapter correction or source review, deliver that requested work and state which build, native execution and comparison steps remain unperformed. Source review and CPU simulation cannot establish acceptance of the native POC.
Gather inputs and choose sources
Before editing, identify:
the target engine or adapter code and build entry point;
the data source or fixture, its schema, and how the engine reads it today (its own scan layer, or none);
the query, operator sequence, or CPU implementation;
the expected output or CPU/reference result and target-engine semantics; and
the target-engine language, any existing libcudf C++ or cuDF Java integration code, and the cuDF version when identifiable from the code or build environment.
Determine the cuDF entry and exit interfaces from the supplied engine code. Define schema conversion, buffer ownership and release, lifetime, and producer/consumer readiness as part of the POC. Ask the engineer only when the code and tests cannot establish a required choice.
Ask only when a missing input changes the code, correctness, safety, or ability to build and run. Gather only the environment facts needed for this POC.
If the supplied query, CPU behavior, target-engine semantics, and expected result disagree, ask which behavior controls. Do not choose silently.
Use target-engine code and tests, installed public headers, and version-matched official cuDF documentation and source. Treat partner discussions as problem signals, not technical authority.
Build the POC
Establish the named CPU or reference result. Run the reference implementation when it is executable.
Map the requested semantics to public, version-matched cuDF APIs. Handle relevant null, type, order, error, ownership, lifetime, and stream behavior. When native calls can leave GPU work pending, read cleanup after asynchronous work before implementing ownership and exception paths.
Implement the requested operators and minimal engine or adapter glue without changing cuDF mainline. If the required public cuDF API is missing, preserve any buildable engine-side work, document the smallest cuDF gap, and report
BLOCKEDwhen the POC cannot proceed safely.Build a runnable program and execute the workload on one GPU. Record exact commands and working directories.
State the applicable row-order handling, null and type equality, and floating-point tolerance before comparing the output with the named CPU or reference result.
Fix evidenced defects, then rebuild, rerun, and recompare. Continue until the checks pass or a named blocker remains. Report unsafe boundaries, missing prerequisites, unresolved semantics, and larger engine changes.
Before accepting an asynchronous path, inspect every operation that can throw after submission, including native calls, output allocation and result-wrapper construction. C++ destroys objects declared inside a try block before entering its catch handler: a wait in that handler cannot protect those destroyed owners. Keep input, intermediate and output owners outside the throwing scope, and establish completion before releasing them on failure. On success, wait after the last queued operation, including a device-to-host copy, before the caller reads the result. A wait before the copy does not make its destination ready.
Honor the supplied caller's completion promise even when filtering produces no rows. An empty result can still follow queued work or depend on input readiness. For a result handed between workers, retain its buffer, stream and resource owners and establish the producer-to-consumer dependency. Follow the ownership patterns and validation steps in cleanup after asynchronous work.
Exercise a recoverable allocation failure while work is pending, assert that no owner is released early, and check a subsequent valid call when the engine promises recovery. Treat a failed ownership or readiness check as a failed POC even when normal output values match.
If a required codebase, toolchain, compatible cuDF runtime, GPU, or reference result is unavailable and prevents a required step, report BLOCKED, name the missing prerequisite, preserve completed work, and give the exact next command or check. Do not report the blocked step as run or passed.
POC acceptance criteria and handoff
POC passes only when the source change builds, the program exits successfully, its output matches the named CPU or reference result under the stated comparison policy, and a reliable engine signal or runtime observation confirms that the requested result-producing work ran through cuDF.
Report the native-execution evidence separately from numerical agreement. If reliable confirmation is unavailable, mark native execution unresolved and do not report an overall POC pass. Do not infer native execution from GPU availability or elapsed time. A profiler is not required when another reliable engine signal or runtime observation establishes native cuDF execution.
Return:
the patch and runnable program path;
exact build and run commands with their working directories;
the inputs, selected binding and cuDF version, named CPU or reference result, comparison policy, and observed result;
any available cuDF-path observation; and
unresolved questions and larger engine work, with facts separated from inference.
Keep cuDF and engine responsibilities separate
cuDF provides device-wide algorithms for one GPU. The engine owns query-plan and pipeline orchestration, spill, production fallback, multi-GPU coordination, and distributed execution.
I/O sits on the boundary, and the POC must pick one of two paths and say which. cuDF ships data sources that read local files, remote files, and remote objects directly. The engine can either pass cuDF a path or data source and let cuDF perform the read, or keep its own I/O stack and hand cuDF the bytes in host buffers, usually pinned. Choose the path that matches the supplied engine code: if the engine already has a scan or storage layer that produces host buffers, feed those buffers to cuDF; if it does not, use a cuDF data source. Record the choice, the buffer type (pinned or pageable), and who frees each buffer in the handoff. Caching, prefetch, retries, credentials, and format negotiation stay with the engine and are out of scope.
Write the engine or adapter code needed for the requested POC, including who owns and releases each buffer and how consumers wait for producer work to complete. Report larger engine work separately; do not implement it in the POC.
Performance and profiling
Profiling is optional for an initial POC and is never a blocker: if Nsight Systems cannot be installed or run, report that and continue. When it is available, capture one nsys profile of the run and check that the GPU is busy in the timed region. Report idle gaps, host-side stalls, and synchronous copies; do not fix them in the POC unless asked. Preserve the exact run command and workload inputs so the run can be profiled later.
When performance work is requested, profiling belongs in the same tuning loop. Benchmark the same logical work under stated conditions. Obvious code changes may be validated with benchmark results, but broader diagnosis and performance claims require profile evidence. If profiling cannot run, report the blocker rather than inferring bottlenecks from code alone.
A GPU result that remains slower than the CPU result is not automatically a failed POC. Preserve the implementation and report the measurements, profile evidence collected, observed bottlenecks, and remaining engine work.
Evaluation files
The evals/ directory is for maintainers evaluating this skill. It contains incomplete adapter starters and CPU models used to test host ownership and readiness; these are not cuDF implementations or native-execution evidence. Do not run these fixtures as part of an engineer's POC unless the user requested skill evaluation. Read evals/EVAL.md before evaluating them and use its isolated execution procedure.
Files
- ATTRIBUTION.mdAdded by AutoGineer977 B
- BENCHMARK.md10.7 KiB
- LICENSE29.8 KiB
- LICENSE-APACHE11.2 KiB
- LICENSE-CC-BY-4.018.3 KiB
- SKILL.md9.1 KiB
- THIRD_PARTY_NOTICES.md3.2 KiB
- evals/.reference/Dockerfile.cudf-cpp272 B
- evals/EVAL.md7.4 KiB
- evals/config.yml505 B
- evals/evals.json19.7 KiB
- evals/files/async-copy-cleanup/TASK.md3.1 KiB
- evals/files/async-copy-cleanup/adapter.hpp683 B
- evals/files/async-copy-cleanup/run_checks.pyScript4.9 KiB
- evals/files/async-copy-cleanup/sim_backend.hpp6.2 KiB
- evals/files/async-copy-cleanup/test_adapter.cpp3.6 KiB
- evals/files/worker-result-handoff/TASK.md3.3 KiB
- evals/files/worker-result-handoff/adapter.hpp1.4 KiB
- evals/files/worker-result-handoff/run_checks.pyScript4.9 KiB
- evals/files/worker-result-handoff/sim_backend.hpp6.2 KiB
- evals/files/worker-result-handoff/test_adapter.cpp4.1 KiB
- evals/grader.pyScript11.4 KiB
- references/asynchronous-cleanup.md7.7 KiB
- skill-card.md5.1 KiB
- skill.oms.sig9.1 KiB
evals/evals.json
{
"skill_name": "cudf-query-engine-builder",
"evals": [
{
"id": "async-copy-cleanup",
"prompt": "Complete the host-side adapter for our first single-GPU cuDF query-engine proof of concept in /workspace/input/async-copy-cleanup. Read TASK.md and the supplied caller and interfaces, preserve the CPU reference and protected engine behavior, and repair only the allowed implementation. From the task directory run python run_checks.py to compile and execute the supplied tests. Return the patch, exact build/run commands, observed results and any remaining native checks. This environment executes a deterministic CPU simulation of asynchronous backend operations. Its checks establish the host contract only; CUDA/libcudf execution must be reported separately.",
"expected_skill": "cudf-query-engine-builder",
"files": [
"files/async-copy-cleanup"
],
"expected_output": "Repairs the allowed C++ implementation, builds it and runs python run_checks.py. The synchronous adapter preserves the required upload, output allocation, aggregation and wrapper-construction order. Exact sum/count matches the supplied CPU reference for nullable, empty and all-null inputs. Required owners survive queued consumers on normal completion, failure before submission, output allocation failure after upload submission, and result-wrapper failure. Each exercised std::bad_alloc propagates as the original error, queued work is completed before dependent owners are released, and a subsequent valid call succeeds. Reports actual commands and all supplied test outcomes without claiming the CPU simulation proves native cuDF execution.",
"assertions": [
"Produces a concrete repair only to adapter.hpp, preserving public signatures, protected caller/checker and the required submission order.",
"Runs python run_checks.py, compiling the repaired C++20 program and reporting its actual full test outcome.",
"Returns exact sum/count for nullable, empty and all-null inputs.",
"Keeps every required buffer, resource and stream owner valid until queued consumers finish on success and the exercised allocation failures.",
"Preserves std::bad_alloc and verifies recovery with a subsequent valid call.",
"Distinguishes host-contract simulation results from unperformed native CUDA/libcudf validation."
]
},
{
"id": "worker-result-handoff",
"prompt": "Complete the host-side adapter for our first cuDF execution path in /workspace/input/worker-result-handoff. Our engine sends a batch between workers, then consumes the returned result. Read TASK.md and the supplied interface, fix the allowed implementation, and run python run_checks.py from the task directory to compile and execute the supplied checks while preserving the existing caller and CPU reference. Return the patch, exact commands, observed comparison and remaining work. The supplied backend is a deterministic CPU simulation of queued GPU work, so a successful simulator run is not evidence that native cuDF ran.",
"expected_skill": "cudf-query-engine-builder",
"files": [
"files/worker-result-handoff"
],
"expected_output": "Repairs adapter.hpp, builds it and runs python run_checks.py. submit returns with work still queued, honoring the caller's asynchronous contract. The returned QueryResult owns the input, staged/output buffers, producer and consumer streams, and allocation resource for their needed lifetimes. Consumer work waits for the correct producer dependency. get returns completed backend sum/count and can be called repeatedly; destruction before get also completes dependent work safely. Two outstanding results can be consumed independently in either order. Explicit CPU fallback remains allowed only when selected and is labeled Origin::cpu; a backend-selected request returns the backend operation's result. All supplied checks pass with clean ownership/queued-work audits. Reports actual simulator results separately from native cuDF checks still required.",
"assertions": [
"Repairs only adapter.hpp and runs python run_checks.py with an observed full test result.",
"Preserves asynchronous submit, returning before queued work executes.",
"Retains required buffers, streams and resource owners after caller references expire, and establishes producer-to-consumer readiness.",
"Returns exact backend sum/count for normal, empty and all-null inputs; repeated get and independent outstanding results remain correct.",
"Safely completes dependent work when a result is destroyed before get.",
"Preserves explicit CPU fallback and labels its origin truthfully, without treating simulator Origin::backend as native cuDF evidence."
]
},
{
"id": "owning-result-context",
"prompt": "Complete the engine adapter for its first native, single-GPU POC. The CPU reference concatenates the supplied INT64 batches in arrival order and returns an owning global OFFSET/LIMIT result, preserving duplicates. The engine permits a synchronous POC. Here are the full relevant C++ interface contracts for this source review:\n\nstruct EngineContext {\n Stream stream;\n Resource output_resource;\n void finish() noexcept; // completes all submitted work; failure is outside this fixture\n};\nstruct Batch { std::unique_ptr<NativeTable> table; };\nusing Inputs = std::vector<std::shared_ptr<Batch>>;\nstruct NativeTable { /* destruction uses its allocation Resource and Stream */ };\nstd::unique_ptr<NativeTable> submit_concat_slice(\n Inputs const&, int64_t offset, int64_t limit, Stream&, Resource&);\n// This version-matched public-cuDF wrapper submits result-producing work,\n// returns an owning table, may return before completion, and may throw\n// std::bad_alloc after submitting work. It does not retain Inputs or context.\nstd::unique_ptr<Descriptor> make_descriptor(NativeTable const&);\n// make_descriptor may throw std::bad_alloc.\n\nThe initial adapter is:\nstruct Result {\n std::unique_ptr<NativeTable> table;\n std::shared_ptr<EngineContext> context;\n std::unique_ptr<Descriptor> descriptor;\n};\nResult run(Inputs inputs, std::shared_ptr<EngineContext> ctx,\n int64_t offset, int64_t limit) {\n Result out;\n out.table = submit_concat_slice(inputs, offset, limit,\n ctx->stream, ctx->output_resource);\n out.context = ctx;\n out.descriptor = make_descriptor(*out.table);\n ctx->finish();\n return out;\n}\n\nThe caller may drop its original context reference immediately after return. A result's NativeTable must be destroyed before its allocator and stream. Offset and limit are nonnegative and supported arithmetic fits INT64. Supply corrected C++ for Result and run using only these interfaces. Explain what the patch proves, give an executable-test protocol for the owning result, and state the implementation/execution status. No compiler, native runtime, test output or repository is attached to this source-review request. Do not invent executions.",
"expected_skill": "cudf-query-engine-builder",
"files": [],
"expected_output": "Corrects both ordinary result destruction order and exceptional pending-work lifetime. Declares/retains context so table and descriptor are destroyed before context, and keeps required input owners plus context outside the throwing scope until finish covers all submitted work. Catches exceptions around native submission and descriptor construction, calls finish before local owners/table can unwind, then rethrows the original exception. A correct synchronous strategy may finish immediately after submit before descriptor construction, but must also catch submit itself throwing after work was queued. The owning result is preserved rather than returning a view. The test protocol compares exact ordered CPU values across empty/cross-batch/bounds cases, drops the caller context, injects recoverable post-submission host allocation failure with pending-work observation, checks release order, and retries in the same context. Does not report a native POC pass or executed tests because only source-review inputs were supplied.",
"assertions": [
"Shows corrected C++ that ensures table/descriptor destruction precedes their required context owners.",
"Retains inputs and context across native calls that can throw after submitting work.",
"Completes pending work before releasing dependent objects on both success and exception paths, preserving the original exception.",
"Does not propose only a successful-return wait or a guard destroyed after the owning objects it must protect.",
"Keeps an owning native result and preserves the full OFFSET/LIMIT operation.",
"Defines exact comparison and failure-injection checks and marks build/native execution unperformed."
]
},
{
"id": "engine-buffer-read-path",
"prompt": "Implement the minimal adapter for a first single-GPU cuDF POC using this query engine's existing storage interface. The CPU path already decodes an encrypted object through the engine scan layer and applies the selected query. The same decoded Parquet byte stream must feed the native POC; object paths/credentials are private to the scan layer. No production I/O policy work is requested.\n\nThe engine exposes:\nstruct ScanLease {\n std::shared_ptr<Bytes> owner;\n std::span<std::byte const> bytes;\n bool pinned; // false for this fixture\n};\nScanLease engine_scan(ScanToken);\nstruct GpuTable; struct HostAnswer;\nstd::unique_ptr<GpuTable> read_parquet_host(\n std::span<std::byte const>, Stream&);\n// a version-matched public-cuDF wrapper, may queue reads from the supplied host bytes;\n// does not retain their owner and may throw after submitting work\nstd::unique_ptr<GpuTable> evaluate_selected_query(GpuTable const&, Stream&);\n// a version-matched public-cuDF wrapper for the whole selected query;\n// may queue work and may throw after submission\nHostAnswer collect(GpuTable const&, Stream&); // may throw; result readable after finish\nvoid finish(Stream&) noexcept; // completes submitted work in this fixture\n\nThe initial code is:\nHostAnswer run(ScanToken token, Stream& stream) {\n auto table = read_parquet_host(engine_scan(token).bytes, stream);\n auto result = evaluate_selected_query(*table, stream);\n auto answer = collect(*result, stream);\n finish(stream);\n return answer;\n}\n\nWrite the corrected function using these wrappers, with explicit ownership on normal and exceptional paths. State the buffer type and the chosen I/O boundary. The scan token is not a file path. You have the CPU result schema but no build environment, input file or expected row values in this request. Give the next concrete validation steps and current POC status. Do not claim a new filesystem reader or a completed runtime comparison.",
"expected_skill": "cudf-query-engine-builder",
"files": [],
"expected_output": "Keeps the existing engine scan and passes its host bytes to cuDF, without treating ScanToken as a path or introducing a new reader/credential/cache/retry subsystem. Retains the ScanLease owner, input GpuTable and query result in an outer scope; a try/catch covers every operation after submission and calls finish before those owners unwind, then rethrows. Establishes completion before returning the HostAnswer. Records that source bytes are pageable, retains ownership through the read, and does not describe them as pinned or require a production pinned-memory redesign. Names unavailable input/reference/build/runtime as prerequisites to running the native POC; provides build/run/CPU comparison and native-result-observation steps without fabricated results.",
"assertions": [
"Provides a concrete corrected function retaining the ScanLease owner through all queued uses of its bytes.",
"Retains intermediate native owners until dependent consumers complete on exception as well as success.",
"Uses the existing engine host-buffer path and does not interpret ScanToken as an accessible object/file path.",
"Correctly identifies the supplied source bytes as pageable.",
"Preserves the complete selected query without adding production caching, retry, credential or distributed work.",
"Reports missing execution inputs as blockers and separates the proposed patch from unperformed runtime validation."
]
},
{
"id": "conflicting-query-reference",
"prompt": "Add the first native cuDF path to this query-engine adapter. The engineer supplied this selected query and CPU code together:\n\nSelected query: SELECT SUM(amount * rebate), COUNT(*) FROM rows\nWHERE sale_day >= 20230101 AND sale_day < 20240101\nAND rebate >= 250 AND rebate <= 450 AND units < 12.\nThis POC's aggregate contract says an empty selection returns {sum:0,count:0}.\n\nstruct Row { int day; int64_t amount; int rebate; int units; };\nAnswer cpu(std::vector<Row> const& rows) {\n Answer out{0,0};\n for (auto const& r : rows)\n if (r.day>=20230101 && r.day<20240101 &&\n r.rebate>=250 && r.rebate<=450 && r.units<=12) {\n out.sum += r.amount*r.rebate; ++out.count;\n }\n return out;\n}\nFixture: [{20230601,100,300,11}, {20230601,100,300,12}]\nSaved reference: {sum:60000,count:2}\n\nPublic libcudf can express every operation. The current adapter's GPU function is still unimplemented. Give the exact next implementation action, including any question that changes the code, and provide a compact test table covering the supplied fixture and the query's numeric/date boundaries. Explain whether you can choose a single correct GPU implementation now. Do not silently change the query, CPU code or saved reference.",
"expected_skill": "cudf-query-engine-builder",
"files": [],
"expected_output": "Identifies the exact conflict: selected query units<12 produces sum30000,count1 on the fixture, while CPU units<=12 and saved reference produce sum60000,count2. Asks the engineer which behavior is authoritative before committing one GPU predicate or changing the reference. Keeps useful pending work bounded: version/public API mapping and a boundary table can be prepared, but semantic selection is blocked. States both alternatives in the test table; covers units11/12/13, date lower included and upper excluded, rebate250/450 included and249/451 excluded, exact INT64 arithmetic under supported bounds. Does not turn absence of a GPU speedup into failure or assume the saved reference overrides the query.",
"assertions": [
"Computes both conflicting results correctly and names the exact < versus <= mismatch.",
"Asks which behavior controls before selecting the GPU predicate or modifying CPU/reference behavior.",
"Does not silently repair one supplied source or assert overall POC completion.",
"Provides concrete tests for the supplied fixture and numeric/date boundaries with stated expected outcomes or clearly labeled unresolved alternatives.",
"Preserves the requested full native query as the implementation target once semantics are resolved."
]
},
{
"id": "native-result-acceptance",
"prompt": "Finish a first native cuDF proof of concept for an engine's existing query interface. The current adapter builds and produces the same output as its named CPU reference:\nAnswer gpu(HostRows const& rows, Stream& stream) {\n auto answer = cpu(rows);\n launch_marker(stream);\n synchronize(stream);\n return answer;\n}\n\nObserved commands: 'cmake --build build -j2' exited0; './build/query cpu smoke.json' returned {sum:30000,count:1}; './build/query gpu smoke.json' returned {sum:30000,count:1}.\nObserved runtime: one CUDA marker kernel; result-producing libcudf operations=0. Nsight Systems cannot run in this environment. The GPU host/toolchain itself is available.\n\nThe installed adapter header offers these version-matched wrappers:\nstd::unique_ptr<DeviceRows> upload(HostRows const&, Stream&);\nstd::unique_ptr<DeviceAnswer> cudf_selected_query(DeviceRows const&, Stream&);\n// Implements the complete selected query with public libcudf,\n// increments a protected result-producing operation counter, returns owning result.\nAnswer download(DeviceAnswer const&, Stream&); // readable after synchronize\nvoid synchronize(Stream&) noexcept; // completes submitted work for this fixture\nAll wrappers may throw after submitting work except synchronize.\n\nGive corrected C++ for gpu using these interfaces, preserving the existing CPU path. Define the checks required to accept the revised POC, and assess the current observed run. Include what to do about unavailable profiling. There is no execution result for your revised code yet.",
"expected_skill": "cudf-query-engine-builder",
"files": [],
"expected_output": "Rejects the observed original run as native POC acceptance despite exact numerical agreement and a CUDA marker. Writes a replacement that uploads original rows, invokes cudf_selected_query and downloads that actual DeviceAnswer; CPU answer computation is removed from the GPU function while CPU path remains unchanged. Holds native owners outside the throwing scope and synchronizes on success and catch before releasing owners, then propagates the original error. Requires rebuild/rerun, exact comparison under the named CPU policy and the protected result-producing counter tied to the queried output. Nsight unavailability is recorded but is not a first-POC blocker when reliable engine evidence is available. Reports corrected code unexecuted and no overall native pass yet; absence of measured speedup alone is not failure.",
"assertions": [
"Explains why matching CPU values plus an unrelated CUDA marker do not prove native result-producing execution.",
"Provides a concrete adapter replacement whose returned value depends on cudf_selected_query.",
"Preserves owners across all potentially throwing queued operations and completes consumers before cleanup.",
"Requires rebuilt/reexecuted output comparison and reliable result-producing cuDF evidence before POC acceptance.",
"Treats profiler absence as optional for this initial POC while keeping native execution evidence mandatory.",
"Does not claim the revised implementation was built, executed or passed."
]
},
{
"id": "missing-engine-input",
"prompt": "Build my query engine its first native cuDF GPU execution path and show that its output matches the CPU implementation. I have not supplied the repository, query, schema or CPU reference yet.",
"expected_skill": "cudf-query-engine-builder",
"expected_output": "Asks for the target-engine code/build entry point, selected query or CPU implementation, input schema/fixture and expected result. Does not invent an engine or claim code was built or executed. Identifies the missing prerequisites as blocking implementation.",
"assertions": [
"Identifies the missing target-engine inputs.",
"Asks focused questions needed to establish the actual POC.",
"Does not fabricate build, GPU execution or correctness results."
],
"files": []
},
{
"id": "dataframe-negative",
"prompt": "I only need a pandas expression for a small CPU-only DataFrame named sales with columns region and revenue. Return total revenue by region, preserving missing region keys. No GPU or query-engine integration is involved.",
"expected_skill": null,
"expected_output": "Provides a pandas groupby expression equivalent to sales.groupby(\"region\", dropna=False)[\"revenue\"].sum(), without activating the query-engine builder or proposing a native GPU integration.",
"assertions": [
"Does not load the query-engine builder skill.",
"Uses dropna=False to retain missing region keys.",
"Does not introduce GPU setup or engine integration work."
],
"files": []
}
]
}
Requirements and compatibility
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Attribution and licence
- Created by
- Joe Sack
- Publisher
- NVIDIA (Official)
- Distributed by
- NVIDIA
- Source
- NVIDIA/skills · skills/cudf-query-engine-builder · commit fce3cca
- Licence
- Apache License 2.0 (redistribution allowed)
- ATTRIBUTION.md (written by AutoGineer)
- Synced
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