Development

Programming, frameworks, implementation, frontend, backend, and app development

skills in category: 66,450
pages available: 2,769

Security grades appear on each card once the skill has been scanned. Newly imported skills may briefly show without a grade until the backfill job runs.

Open in full browser

Browse development skills

Showing 14,257–14,280 of 66,450 skills

Rpc And Api ContractsAThe contract between two services and how it changes without a coordinated deploy: partial failure as a first-class outcome, an error surface a machine caller can act on (stable extensible codes, outcome certainty, retry conditions, RFC 9457), compatibility in both directions and expand-then-contract, versioning under an explicit compatibility policy, and choosing REST, gRPC or messaging on observable conditions. Use when a client branches on an error message string, when a field is renamed o...developmentgojavaVotes: 0GitHub stars: 2
Retries And BackoffARetry as a policy with a cost: classifying a failure as transient, permanent or ambiguous before retrying anything; why a timeout is ambiguous and safe to retry only under idempotency or reconciliation; capped jittered backoff; aggregate retry budgets plus per-call limits; one layer owning the end-to-end policy; and honouring 429, Retry-After and the remaining deadline. Use when a catch block retries on Exception or on a message substring, when backoff has no jitter, when several layers each ...developmentrustjavaVotes: 0GitHub stars: 2
Requirements And AcceptanceATurning a request into something buildable and checkable before writing code: separating the requirement from the implementation someone already chose, finding the ambiguities that change the work, naming assumptions where they can be contradicted, writing acceptance criteria that a test can be derived from, and surfacing contradictions instead of resolving them silently. Use before implementing a ticket whose edge cases are unstated, when a request names a solution rather than a need, when "...developmentgojavaVotes: 0GitHub stars: 2
Repository PatternAThe repository as a collection-like boundary over domain objects, with aggregate-root write boundaries in DDD: what belongs behind it, where queries and read models fit, and when a redundant CRUD wrapper can be removed without losing a useful contract. Use when a repository is being added for a child entity, when a generic or base repository is proposed, when repository methods carry business verbs (cancelExpired, activateEligible), when a managed entity escapes through the repository interfa...developmentgojavaVotes: 0GitHub stars: 2
Remote Facade And DtoADesigning what crosses a remote boundary: a Remote Facade providing coarse, business-shaped operations, and DTOs carrying the data in one round trip — plus when a DTO earns its mapping cost. Use when an API mirrors the domain model method for method, when a client makes five calls to render one screen, when JPA entities are serialised to clients, when a DTO is a field-for-field copy of an entity, when adding a field means editing seven classes, when internal fields appear in a public payload,...developmentrustjavaVotes: 0GitHub stars: 2
Refactoring AutomationAApplying repeatable Java changes with IDE refactoring, OpenRewrite, structural search, compiler tooling or hand edits; checking tool coverage and making large diffs reviewable, reproducible and reversible. Use when one edit spans many files, a framework or library migration must run repo-wide, a rename reaches strings and configuration, regex is proposed for Java source, a generated diff is too large to review line by line, automated refactoring changed behaviour, or a cleanup needs recurrenc...developmentgojavaVotes: 0GitHub stars: 2
Skills DirectorySkills Directory 3 slots · $399/mo · one ad per page · sponsors can never buy grades.See placements
Reading Jit AssemblyAReading the machine code HotSpot actually emitted: installing hsdis, driving -XX:+PrintAssembly and JMH perfasm, telling the verified entry point and prologue from the method body, and confirming or refuting a hypothesis about an optimisation from the instructions themselves. Use when a claim about an optimisation needs proof at the instruction level, when PrintAssembly prints hex bytes instead of mnemonics, when PrintOptoAssembly on a product JDK unexpectedly prints only banner lines, when t...developmentrustjavaVotes: 0GitHub stars: 2
Reactive BackpressureABackpressure in reactive and asynchronous pipelines: Reactive Streams request semantics, operators that reshape demand, bounded buffers and overflow strategies, blocking inside a non-blocking pipeline, and measuring where demand is actually being throttled. Use when memory grows in proportion to time under load, when a sequence terminates with an unexpected overflow error, when onBackpressureBuffer is used with no size or no BufferOverflowStrategy, when a refactor replaced a Reactor pipeline ...developmentgojavaVotes: 0GitHub stars: 2
Reactive And Virtual Thread SelectionAChoosing between a reactive pipeline and thread-per-request on virtual threads, and deciding where they legitimately coexist: what each model actually gives you, where backpressure comes from in each, memory per in-flight request versus per idle connection, the diagnosability difference, and the framework configuration that decides which model a request runs under. Use when a team proposes migrating away from WebFlux or towards it, when virtual threads are described as making reactive obsolet...developmentjavareactVotes: 0GitHub stars: 2
Rate Limiting And Load SheddingAChoose policy quotas and saturation-based admission: limit identity, charged work, burst and window semantics, distributed budgets, early rejection, fairness, deadlines and recovery. Use when replica-local limits multiply a quota, window-boundary bursts break the contract, rejection amplifies retries, or a service overloads while clients remain within quota. Covers token/leaky buckets, fixed/sliding windows, 429/503 and meaningful Retry-After guidance. Not queue arithmetic (littles-law-and-qu...developmentrustgoVotes: 0GitHub stars: 2
Queueing ModelsAChoosing, parameterising and falsifying queueing models: M/M/1, M/M/c, M/G/1, finite/loss and closed networks; Erlang C/B, Pollaczek–Khinchine, Kingman/Allen–Cunneen, variability, queue topology and what model assumptions permit. Use when a predicted wait time disagrees with the measured one, when latency is far worse than utilisation suggests, when service times are bimodal or GC-spiked, when arrivals are retries or cron bursts rather than independent users, when Erlang C must be computed fo...developmentjavaVotes: 0GitHub stars: 2
Query Objects And SpecificationsAExpressing queries as objects that can be composed, named and tested — Query Object, Specification, criteria builders, derived repository methods and explicit SQL — and choosing between them per query rather than adopting one style everywhere. Use when repository interfaces have grown dozens of findByAAndBAndCOrderByD methods, when a search screen with optional filters is being built by concatenating strings, when a Specification chain has become unreadable or produces a query nobody can pred...developmentrustjavaVotes: 0GitHub stars: 2
Quality GatesAChoosing which automated checks a change must pass, and making them cheap enough that they stay switched on: matching the gate set to the change's risk rather than running everything on everything, where each gate belongs (pre-commit, pull request, main, release), the Java toolchain that enforces each class of defect, ratcheting a gate onto a codebase that already violates it, and what to do when a gate goes red. Use when setting up or trimming a pipeline, when the build is slow enough that p...developmentgojavaVotes: 0GitHub stars: 2
Project ValhallaAEvaluating Project Valhalla value-class proposals and Early-Access builds without presenting draft syntax or flattening heuristics as released Java behavior. Use when code or documentation claims value classes remove identity, guarantee flattened storage, eliminate boxing, change object layout, or are available in a particular JDK; and when designing an experiment for a future migration. Does not replace current object-layout measurement (object-layout-and-footprint), escape-analysis diagnosi...developmentgojavaVotes: 0GitHub stars: 2
Postgresql PerformanceADiagnosing and tuning PostgreSQL 17/18 from engine evidence: MVCC tuple versions, VACUUM/freeze and bloat, HOT updates and visibility maps, plans and cardinality, work memory/spills, WAL and checkpoints, locks/SSI, connection processes and PgBouncer session semantics, plus pgjdbc prepared-plan, batch, and fetch behavior. Use when the symptom or change depends on PostgreSQL internals. Not generic query-plan, ORM, or HikariCP sizing guidance.developmentjavasqlVotes: 0GitHub stars: 2
Poison Messages And DlqAWhat happens to a message that cannot succeed: separating the permanently poison message that fails on its own content from the transiently blocked one whose dependency is down, and why an attempt counter cannot tell them apart; the dead-letter queue as a design with an owner, an alert and a redrive path; the record captured beside the payload; and the head-of-line decision in a partitioned log, where skipping a record trades a complete effect sequence for progress. Use when a consumer retrie...developmentgojavaVotes: 0GitHub stars: 2
Performance Regression CiADesigning trustworthy performance-regression gates: defining the decision and smallest important regression, preserving independent experimental units, calibrating noise and power, comparing compatible JMH results, handling multiplicity and drift, separating screening from confirmation, and operating secure baseline promotion. Use when performance results should influence merge, when a threshold or statistical test lacks an empirical error budget, when JMH scoreError is treated as a two-build...developmentrustjavaVotes: 0GitHub stars: 2
Performance MethodologyAThe investigation process for performance work: defining measurable goals, recording a baseline, characterising before diagnosing, falsifiability, fixed-work speedup bounds, experimental design, and validating by mechanism rather than by coincidence. Use when starting a performance investigation, when a fix is credited to a deploy that also restarted the process, when an optimisation is proposed without a measurement, when a benchmark result changes with the duration of the run, when an inves...developmentgojavaVotes: 0GitHub stars: 2
Performance Incident ResponseACoordinating a production performance incident from impact declaration through evidence-preserving triage, coordinated mitigation, recovery validation and a blameless causal postmortem. Use when a latency, throughput, saturation or resource regression requires a war room; when responders are changing JVM flags before preserving evidence; or when MTTD, mitigation time and recovery time are being conflated. Evidence acquisition belongs to incident-evidence-capture; technical diagnosis to perfor...developmentgorailsVotes: 0GitHub stars: 2
Performance Engineering ProgramAEstablishing an organization-wide performance engineering program through measurable maturity evidence, service ownership, SLO and baseline adoption, regression gates, incident learning and a rotating champion model. Use when performance depends on one specialist, teams apply different evidence standards, a maturity assessment needs concrete next actions, or a rollout must turn isolated profiling into a durable operating discipline. Does not design individual SLOs, benchmarks, alerts or profi...developmentgoperformanceVotes: 0GitHub stars: 2
Pause AttributionAAttributing an observed production pause to a layer: decomposing it across time-to-safepoint, safepoint operation, cleanup and host effects, correlating the GC log, the safepoint log, JFR and OS signals by timestamp, and proving which layer owns the missing milliseconds. Use when application p99 far exceeds what the GC log accounts for, when "Reaching safepoint" is large while "At safepoint" is small, when two profilers disagree about hot paths, when a safepoint-log analyser reports zero even...developmentrustjavaVotes: 0GitHub stars: 2
Patterns And Modern FrameworksAWhich classical enterprise patterns a modern Java and Spring stack already implements, which it only partly implements, and which it does not implement at all — plus the modern Java expression of each. Use when a repository interface is written over Spring Data, when a unit of work or identity map is built over JPA, when a front controller is hand-rolled, when a caching layer is written over the caching abstraction, when an entity is written as a mutable bean because "JPA requires it", when a...developmentgojavaVotes: 0GitHub stars: 2
Pattern Selection And CompositionAChoosing enterprise patterns from forces rather than familiarity, and combining them into an architecture whose parts reinforce rather than fight each other: the selection criteria that discriminate, the compositions that work, the pairs that conflict, and the relationship graph. Use when a design is starting and the patterns are about to be chosen by habit, when a pattern name is proposed before the problem is stated, when two chosen patterns produce friction, when a reference architecture i...developmentgosqlVotes: 0GitHub stars: 2
Orm Structural MappingAMapping the structure of an object model onto tables: Identity Field, Foreign Key Mapping, Association Table Mapping, Dependent Mapping, Embedded Value and Serialized LOB. Use when choosing an identifier strategy or when a generated identity breaks batching, when a bidirectional association updates the wrong side and no foreign key is written, when a many-to-many link already has attributes, when child rows are given repositories of their own, when a value type is flattened into columns or hi...developmentgojavaVotes: 0GitHub stars: 2