I design execution-based evaluations for terminal-based coding agents—real engineering environments where success is decided by a deterministic grader, not by how convincing the answer sounds.
Generated code can look excellent while restoring the wrong database state, leaking future data, trusting a broken journal, or hardcoding one visible fixture.
My work turns those distinctions into measurable outcomes. The benchmark owns the environment, the protected truth, and the scoring boundary. The model owns only its investigation and repair.
02 / Benchmark construction
From realistic failure to defensible signal.
Hardness is designed. Correctness is proved. Each layer exists to remove an easier explanation for success.
01
Construct
Anchor the task in a real engineering failure with enough ambiguity to require investigation—not transcription.
02
Force
Use cost models, baselines, and ablations to prove the intended reasoning is necessary before building the grader.
03
Isolate
Package dependencies, fixtures, state, and runtime boundaries so every agent receives the same problem.
04
Verify
Score observable behavior, persistent state, artifacts, and invariants rather than plausible-looking code.
05
Attack
Pressure-test shortcuts with mutations, hidden cases, no-op controls, path attacks, and regression checks.
06
Analyze
Review trajectories to find wrong assumptions, missed signals, shallow fixes, and weak self-verification.
03 / Selected evaluations
Problems that resist the first plausible answer.
Representative work across storage, systems, ML infrastructure, temporal data, and release engineering.
01
Storage systems · Crash recovery
Coherent—but stale.
evidence / storagelive invariant
commit nrecoverstale
STRUCTURE VALID STATE WRONG
A shadow-paged embedded key-value store recovered into a structurally valid database that represented the wrong transactional moment. Ordinary corruption checks passed; only reasoning about durability and logical state exposed the failure.
transaction durability
recovery semantics
persistent state
logical invariants
EvidenceIndependent model trajectories reproduced the failure. Submission passed external technical review.
02
Systems · Emulator repair
Three semantics, one correct repair.
evidence / emulatorlive invariant
DMA02IRQROTAXISCFG
VISIBLE PASS HOLDOUT ARMED
A terminal benchmark hid interacting defects across DMA grant width, rotating interrupt priority, and axis modulus behavior. Visible evidence permitted a tempting partial repair; held-out cartridges forced the complete system model.
A fraud-feature task tested whether agents could derive historical signals without leaking future transactions. The verifier evolved to challenge global-statistic shortcuts, cross-run state, over-wide outputs, and solutions that looked predictive for the wrong reason.
temporal leakage
future invariance
AUC calibration
stateful shortcuts
EvidenceAccepted after verifier hardening, adversarial replay, and genuine difficulty calibration.
04
ML infrastructure · Recovery
Recover the last usable global commit.
evidence / checkpointlive invariant
global commit
JOURNALS ALIGNED HASHES VERIFIED
A distributed checkpoint resharding task required validating coordinator and rank journals, transaction identity, epochs, logical ownership, physical ranges, aliases, and block hashes before selecting a recoverable commit.
transactional recovery
tensor topology
binary integrity
cross-rank consistency
EvidenceAccepted through pass, adversarial, quality, trial, and final evaluation gates.
05
Build & release · Reproducibility
Byte-for-byte means every byte.
evidence / archivelive invariant
0755bin/runnerepoch
0644pkg/app.txtutf-8
0755pkg/app/empty
0777currentsymlink
sha256byte-exact
A deterministic release-rebuild task covered timestamp clamping, UTF-8 path ordering, executable-mode normalization, archive ownership, symlinks, empty directories, and gzip metadata under a pinned Linux environment.
reproducible builds
filesystem metadata
path ordering
cross-platform parity
EvidenceVerifier review exposed missing discriminators, turning a green-looking result into a sharper coverage model.
04 / Deterministic grading
How correctness gets proved.
A grader should fail for the same reason the production system would fail—not because a solution differs stylistically from a reference patch.
01
Behavior
APIs, files, processes, databases, and state transitions must match the contract.
02
Protected truth
Held-out fixtures and expected state remain outside the submitted program's trust boundary.
A correct oracle must pass; no-op, partial, malicious, and hardcoded solutions must fail.
05
Mutations
Deliberately wrong implementations prove each important requirement changes the score.
06
Reproducibility
Pinned dependencies and architecture-aware runs separate platform drift from task evidence.
05 / Trajectory analysis
What model failures reveal.
A useful miss diagnoses capability. It shows where investigation, system modeling, or verification stopped being reliable.
01
Surface repair
The symptom disappears, but the model never discovers the state transition or invariant that caused it.
02
Weak verification
A patch is written and a convenient test passes; the original failure is never recreated end to end.
03
Sticky system model
An early architectural assumption survives even after logs, artifacts, or runtime behavior contradict it.
04
Visible-case optimization
The implementation fits public examples while violating the broader invariant those examples represent.
05
Over-editing
The agent changes more than the responsible layer, increasing regression risk and hiding the causal fix.
06 / Engineering context
Production engineering underneath the benchmark.
Five years across APIs, databases, infrastructure, asynchronous workflows, and AI applications make the tasks feel like engineering—not puzzles wearing code.
AI training & evaluation
Handshake AI
Software-engineering tasks · automated grading · model behavior
Agentic benchmark evaluation
Mindrift
Task construction · reproducible environment · multi-model failure analysis
Senior software engineering
Production systems
Backend architecture · databases · Docker · Linux · integrations