Diagnoses and fixes non-deterministic test failures at root cause instead of masking them with retries — classify the flake (test-order/shared-state pollution, async timing/sleep…
Designs full-text and vector search infrastructure — Elasticsearch/OpenSearch mappings and analyzers, vector index parameters (HNSW M/efConstruction, IVF nlist/PQ), BM25+vector…
Prevents numeric-precision and units defects by enforcing epsilon/ULP/relative float comparison, Kahan/Welford stable accumulation, NaN/Inf and div-by-zero guards,…
Builds semantic/vector search — pick an embedding model + dimensionality (and whether to truncate Matryoshka dims) and the matching distance metric (cosine/dot/L2, normalize to…
Handles full PDF lifecycle — extracts text/tables, merges/splits, rotates, watermarks, fills forms, encrypts/decrypts, and OCRs scanned pages.
Integrates a THIRD-PARTY identity provider via OpenID Connect — "Log in with Google/GitHub/Microsoft/Apple" or acting as an OAuth client to a third-party API.
Design and orchestrate multi-agent AI systems with knowledge harvesting, agent collaboration, and learning loops.
Plans and executes incremental legacy modernization with the strangler-fig pattern — pins current behavior with characterization/golden-master tests, carves the narrowest seam,…
Implements authentication and session management (JWT issuing/verification, refresh rotation, sessions, cookies, OAuth2/OIDC flows, RBAC checks) when building or fixing how a…
Implements type-safe forms with React Hook Form + Zod (or server-action validation) — schemas, field arrays, multi-step flows, and accessible error handling; used when building or…
Implements distributed mutual exclusion and leader election correctly across processes/nodes — Redis `SET key token NX PX <ttl>` with a unique random token + Lua…
Gets machine-parseable JSON out of an LLM reliably — prefer provider-enforced grammar (OpenAI `response_format:{type:"json_schema",strict:true}`, Anthropic tool-calling /…
Sets up dynamic security testing — coverage-guided fuzzing of parsers and input handlers (libFuzzer/cargo-fuzz/AFL++/go test -fuzz/atheris) and DAST scanning of a running app…
Designs and evolves gRPC/protobuf service contracts — message and service definitions, unary vs streaming RPC selection, wire-compatible schema evolution (reserved tags, safe vs…
Models a lifecycle (order status, connection, checkout/approval flow, device/job state) as an EXPLICIT finite state machine or statechart instead of boolean-flag soup — enumerate…
Makes calls to flaky dependencies (DBs, HTTP/RPC APIs, queues) survive failure without amplifying it — bounded timeouts on connect/read/total/per-attempt, deadline propagation…
Scaffolds production-grade React/Next.js components with proper props typing, server vs client component boundaries, and composition; used when building or restructuring UI…
Writes and reviews production-grade Bash/POSIX shell scripts with safety rails — set -euo pipefail, quoting, trap cleanup, shellcheck-clean, idempotency, and clear error handling.
Builds realtime push channels over WebSocket/SSE — auth-on-connect, heartbeat/zombie eviction, topic subscribe/publish with per-topic authz and presence, sequence-numbered resume…
Implements secure file/image/video upload to object storage via short-lived presigned URLs or POST policies, with content-type + size validation, magic-byte verification,…
Systematically diagnoses live Kubernetes workload failures — CrashLoopBackOff, ImagePullBackOff, OOMKilled, pending pods, failing probes — by gathering describe/logs/events/node…
Monitors a production ML model for input data drift, prediction drift, and performance decay against delayed labels — using PSI/KS/Chi-square drift tests, train/serve skew checks,…
Eliminates wasted React re-renders by measuring first then fixing — profile with the React DevTools Profiler (flamegraph + "why did this render") and why-did-you-render to find…
Designs event-sourced and CQRS systems — past-tense immutable event schemas, aggregate boundaries with command→validate→emit→apply and expected-version optimistic concurrency,…
Performs FinOps cost optimization on AWS/GCP/Azure — right-sizing instances, spotting idle/orphaned resources, Savings Plans/Reserved/committed-use analysis, storage tiering, and…
Cleans, transforms, joins, reshapes, and aggregates tabular data (CSV/Parquet/DataFrames) with pandas, handling missing values, type coercion, dedup, and time-series resampling.
Designs and validates backup, point-in-time-recovery, and disaster-recovery strategy for datastores — sets RPO/RTO targets, configures snapshot plus continuous WAL/binlog/oplog…
Audits open-source license compliance — resolves SPDX identifiers across the full transitive dependency tree (license-checker/scancode), classifies copyleft (GPL/AGPL/LGPL)…
Implements privacy/data-protection engineering — personal-data inventory/mapping (RoPA), lawful-basis and versioned consent capture, DSAR machine-readable export and…
Designs and stabilizes Playwright end-to-end tests — Page Object Model, role/data-testid selectors, cross-browser, network mocking, visual regression; used when adding or…
Integrates payment, subscription, and billing flows against a payment provider — hosted/PCI-offloaded checkout and payment-intent surfaces, idempotency-keyed money-mutating calls…
Writes and fixes correct async/concurrent code across Python (asyncio), TypeScript (Promises), Rust (tokio), and Go (goroutines/channels), targeting deadlocks, races,…
Sanook constructs, explains, and tests regular expressions for a stated matching goal — building the pattern, generating positive/negative test cases, and validating against them,…
Trains and evaluates a classic (non-LLM) ML model — business-aligned metric selection, leakage-safe train/validation/test splits, Pipeline-scoped feature engineering,…
Builds tamper-evident audit logging — structured actor/action/target/result records for security-relevant events, append-only hash-chained or WORM/object-lock storage, PII-safe…
Externalizes user-facing text into message catalogs keyed by stable IDs and wires locale-correct rendering — ICU MessageFormat plurals/gender/select, named-placeholder…
Builds the producer side of webhooks — you dispatch signed events to customers' HTTPS endpoints. Sign every payload with HMAC-SHA256 over "{timestamp}.{raw_body}" in a versioned…
Adds production observability to a service — structured logging, RED/USE metrics, OpenTelemetry distributed tracing, plus Prometheus/Grafana dashboards and actionable SLO-based…
Hardens an LLM feature against prompt injection, jailbreaks, and unsafe output — isolating untrusted content as data, adding input/output guardrails, an injection classifier,…
Builds Playwright-based scrapers that extract structured JSON from dynamic sites — handling auth, pagination, dynamic content, and schema-shaped output with retry/anti-flake…
Improves changed code for reuse, simplification, readability, and efficiency without changing behavior, then re-runs tests to prove behavior is unchanged.
Architects a SaaS so many customer orgs share infrastructure without leaking into each other — picking an isolation model (shared schema + Postgres RLS, schema-per-tenant, or…
Reviews and writes Kubernetes / Helm manifests for production-readiness: resource requests/limits, probes, security contexts, PodDisruptionBudgets, standard labels, and validation…
Reviews and writes database migrations for safety — lock contention, blocking DDL on large tables, data-loss/destructive operations, missing indexes, and rollback plans.
Audits and fixes technical/on-page SEO — meta tags, Open Graph/Twitter cards, JSON-LD structured data, canonicals, sitemap, robots.txt; used when improving discoverability or…
Audits and fixes markup/JSX for WCAG 2.2 AA compliance — alt text, ARIA, heading order, contrast, keyboard nav, focus management; used before shipping UI or preparing an a11y…
Builds production data grids that stay fast and accessible at 10k–1M+ rows — decide server-side vs client-side sort/filter/paginate by the dataset-fits-in-memory test (client only…
Designs an authorization model — RBAC/ABAC/ReBAC, multi-tenant isolation, resource ownership, and policy-as-code (OPA/Cedar/Oso) — keeping authZ decisions separate from authN…
Produces grounded effort estimates for a task/feature — decomposing into subtasks, assigning size (story points or t-shirt S/M/L), surfacing assumptions, unknowns, and risk…
Publishes a library to a package registry (npm/PyPI/crates) safely — semver decision, correct artifacts (dual ESM/CJS + types, files allowlist), provenance/signing via OIDC, a…
Compares two tables or query results and diagnoses exactly how they differ — row counts, key set differences, per-column value mismatches — for migration and refactor validation.
Configures and optimizes the JS/TS build toolchain — tsconfig plus a bundler (Vite/esbuild/Rollup/tsup/webpack) — for correct module output (ESM/CJS/dual + types), code splitting,…
Produces a design-level STRIDE threat model — decomposes the architecture into a data-flow diagram with trust boundaries, enumerates threats per element, rates them by likelihood…
Drives live incident response and postmortems SRE-style: severity triage (P0–P3), log/metric/trace correlation to find what changed, safe mitigation, comms updates, and blameless…
Resolves non-trivial merge, rebase, and cherry-pick conflicts by reading both sides' intent and combining hunks — handling rename/delete/add-add/binary conflicts, enabling rerere…
Makes operations safe to repeat so retries and at-least-once delivery don't double-charge or double-create — idempotency by design first (PUT/upsert, conditional writes with…
Wires a local multi-service development stack with Docker Compose — app plus backing datastores (Postgres/Redis/Kafka), dependency-ordered healthchecks (depends_on condition:…
Implements feature flags and progressive delivery — kill switches, percentage/targeted rollouts, sticky hashed bucketing, fail-safe evaluation, 1→10→50→100 ramps with…
Defines and runs rule-based data-quality checks — completeness, uniqueness, freshness, range, referential integrity — using Great Expectations-style assertion frameworks.
Rewrites git history safely — interactive rebase (squash/split/reorder/reword/edit), amend, and git filter-repo/BFG to purge a committed secret or large file — using…