A midnight payment outage caused a user to be charged three times because a Lombok‑generated @Data class ignored the superclass requestId in its equals method, breaking idempotency checks; the article explains the root cause, reproduces the bug, and offers concrete guidelines for safe Lombok usage.
The article shows how mismatched business and code vocabularies cause confusion, then guides readers through building a shared glossary, renaming domain objects and types in Java, and enforcing the conventions with a code‑review checklist to keep the ubiquitous language alive in the codebase.
This article explains why Java thread pools need tuning, walks through the seven core ThreadPoolExecutor parameters, provides formula‑based sizing, offers configuration templates for different workloads, shows monitoring and dynamic adjustment techniques, and highlights common pitfalls with concrete code examples.
The article explains why concurrent Excel exports can overload a Java backend, describes a FIFO queue with a fixed capacity to serialize export tasks, shows the full implementation with Spring, EasyExcel and synchronized wait/notify, and discusses test results and remaining limitations.
This article walks through configuring Spring AI on Spring Boot 3.5.0 to convert tool‑calling results among JSON, TOON, XML, CSV, and YAML, presenting two approaches—per‑tool converters and a global delegator—complete with code samples, limitations, and sample output for each format.
Microsoft's new MAI‑Code‑1‑Flash model is now available in IntelliJ, signaling a shift for Java developers from using a single, heavyweight AI model for all tasks to selecting fast, task‑specific models that improve iteration speed, reduce costs, and better match the risk profile of each coding activity.
The article explains why traditional three‑layer architectures let business logic bloat inside services, demonstrates the pitfalls of anemic domain models with a 7,000‑line SalaryService example, and shows how DDD’s rich domain model restores rule ownership and maintainability.
This article lists ten common IntelliJ IDEA pitfalls—slow performance, Lombok errors, broken breakpoints, encoding issues, unwanted Git files, Maven download slowness, class‑not‑found errors, broken shortcuts, MySQL timezone problems, and automatic reformatting—plus step‑by‑step solutions to make the IDE run smoothly for Java developers.
This article presents ten practical Java clean‑code techniques—from meaningful naming and single‑purpose methods to avoiding magic numbers, writing purposeful comments, proper logging, defensive programming, DTO separation, Stream API usage, Optional handling, and safe ThreadPoolExecutor configuration—each illustrated with concrete code examples and explanations.
This article explains Java's immutable String class, covering three ways to instantiate strings, methods for length, concatenation (concat and +), character access, substring extraction, splitting, replacing, searching, and comparison using equals versus ==, with concrete code examples and key rules for each operation.
The article explains that Spring AOP cannot intercept methods marked as private, static, or final because JDK dynamic proxies only work on public interface methods and CGLIB subclasses cannot override such methods, leading to static matching but dynamic execution failure, self‑invocation bypass, and complete loss of advice for these method types.
This article explains how to differentiate memory leaks from out‑of‑memory errors, identifies classic GC‑based leak signals, introduces a toolchain (jstat, jmap, MAT, Arthas, JProfiler), walks through a step‑by‑step investigation workflow, lists common leak patterns, presents a real‑world ThreadLocal leak case, and offers preventive measures such as monitoring, regular heap dumps, code review, and stress testing.
The article explains how the Template Method pattern pervades Spring’s core classes—such as JdbcTemplate, AbstractApplicationContext, and various *Template classes—by fixing the overall algorithm flow while delegating the variable steps to subclasses, and contrasts it with the Strategy pattern.
This article explains Java's 16‑bit char type, how Unicode literals are written, the role of the Character wrapper class, boxing and unboxing mechanics, immutability, common static methods, and proper use of escape sequences such as Unicode and quoted strings, with concrete code examples.
An interviewer's question about the difference between epoll and select reveals a tangled web of OS‑level IO mechanisms; this article unpacks user‑space vs kernel‑space, DMA, zero‑copy, buffering, and maps the five Java IO models (BIO, NIO, AIO, etc.) to their underlying system calls.
This article demonstrates how to use Spring Boot 3.5.0 together with Kafka as a high‑throughput message bridge to asynchronously execute long‑running tasks, publish their progress to a Kafka topic, and let clients poll a REST endpoint for real‑time status updates.
This article introduces the Proxy design pattern, explains its core purpose of controlling access without modifying original classes, illustrates everyday analogies, provides a complete Java static‑proxy implementation with interface, real subject, proxy and test code, and summarizes common use cases and distinctions from decorators.
GitHub Copilot Code Review now uses grep, rg, glob and view to actively explore related files in Java pull requests, shifting AI code review from merely commenting on changed lines to investigating the broader impact on transactions, caches, messaging, database queries and system compatibility.
When a Java application suddenly hits 100% CPU and becomes unresponsive, this guide walks through a three-step investigation—identifying the hottest process, the most CPU-intensive thread, and the offending code—using tools like top, jstack, and Arthas, and presents common causes and preventive measures.
The article explains Java SPI’s purpose, how the thread context class loader overcomes parent‑delegation limits, and compares the standard JDK SPI with the extended mechanisms used by Kafka Connect, Elasticsearch, Dubbo, and Spring Boot, providing interview‑ready insights and concrete code examples.
JetBrains has promoted its AI coding agent Junie from beta to general availability, expanding its capabilities from generating Java code to directly operating IntelliJ IDEA’s debugger, planning tasks, accessing project indexes, build configurations, tests, and databases, thereby shifting AI‑assisted troubleshooting from static code analysis to runtime evidence collection.
The article examines the evolution of six singleton implementations in Java, explains why the double‑checked locking pattern requires the volatile keyword to prevent instruction reordering bugs, compares Spring container‑managed singletons with classic GoF singletons, and highlights common pitfalls such as mutable state in singleton beans.
This article launches a Java performance tuning series, explaining why GC logs are the starting point, reviewing the JVM memory model, showing how to enable and read GC logs, dissecting minor and full GC entries, comparing common GC algorithms, and introducing visualization tools to help pinpoint memory issues.
This tutorial walks through Java's core numeric and character utilities, covering number wrapper classes and autoboxing/unboxing, the Number hierarchy, formatted output with printf/format, DecimalFormat patterns, and the Math class’s constants and methods for arithmetic, logarithmic, trigonometric, and random number generation, all illustrated with concrete code examples.
This article explains why many Spring AOP pointcuts fail, clarifies the execution and @annotation expressions, details wildcard usage, presents dozens of concrete pointcut examples, compares their granularity and performance, and offers best‑practice tips to avoid common pitfalls in real‑world Java projects.
Drawing on a decade of production experience, the article presents eight concrete rules for Spring @Transactional—covering transaction duration, proxy limitations, rollback settings, exception handling, read‑only flags, method visibility, bean separation for retries, and logging—to prevent common bugs and ensure reliable database operations.
This article explains the Facade design pattern, illustrates everyday and software scenarios such as hotel front desks and multimedia players, provides a complete Java implementation with subsystem classes, a facade class, and client code, and lists typical business use cases while warning against common misconceptions.
This article walks through the three core behavioral design patterns—Strategy, Observer, and Chain of Responsibility—explaining their intent, showing problematic anti‑patterns, providing step‑by‑step Spring and MQ code implementations, mapping them to real‑world frameworks, and offering interview‑style comparison questions to solidify understanding.
The article explains how the Java final keyword can be applied to classes and methods to prevent inheritance and overriding, provides syntax and concrete code examples—including a final class and a final method in a chess algorithm—and advises using final for safety in constructors.
Spring AOP provides five distinct advice types—@Before, @AfterReturning, @AfterThrowing, @After, and @Around—each with specific execution timing; this guide explains their purposes, execution order, common pitfalls, and offers a complete SpringBoot example with code, Maven setup, and logging demonstrations.
The article details how a sluggish batch‑processing system handling millions of records was redesigned with XXL‑JOB sharding, Redis‑based dynamic task distribution, cursor pagination, and selective transaction scopes, achieving nearly ten‑fold throughput improvement while addressing resource contention, load‑balancing, and reliable result reconciliation.
A four‑month investigation revealed that Jackson’s default object‑mapper consumed over 60% of CPU time during order‑submission requests, causing 900 ms latency; switching to Jackson’s streaming API reduced average response time from 912 ms to 28 ms, cut GC pauses, and increased throughput eight‑fold, while introducing readability and validation trade‑offs.
Spring AI 2.0 adds self‑healing structured output with schema validation and provider‑side constraints, letting Java applications receive reliable JSON objects from large language models, eliminating brittle string‑cleaning code while still requiring business‑level validation.
This article examines the three core challenges—stability, cost, and observability—of running Java AI services in production and presents concrete solutions such as timeout and retry policies, circuit‑breaker fallback, token‑monitoring, caching, tracing, custom metrics, and Docker‑based containerization.
The article introduces the Decorator pattern, explains its purpose of dynamically adding functionality without altering existing classes, illustrates the concept with everyday analogies and a complete Java milk‑tea example, and lists typical use cases and common pitfalls.
The article explains why AI‑assisted coding loops that run instantly on lightweight projects stall in Java microservices, and presents five concrete harness engineering principles—dependency inversion, zero‑intrusion profile isolation, CLI tool integration, CLAUDE.md documentation, and verification scripts—to create a fully local, AI‑friendly development environment.
The article explains the fundamental design flaws of java.util.Date, why a code‑scan rule forces its removal, and provides a step‑by‑step guide to replace Date and related utilities with the modern java.time API, including concrete code transformations and migration tips.
The article explains why effective logging is crucial for Java applications, compares proper and improper logging practices with SLF4J and Logback, and provides fourteen concrete best‑practice guidelines—including correct logger setup, level usage, placeholders, asynchronous and structured logging—to avoid performance degradation and security risks.
This article explains the four essential structural design patterns—Proxy, Decorator, Adapter, and Facade—detailing their core concepts, real‑world Java/Spring use cases, code implementations, and interview‑focused comparisons to help developers master enterprise‑level architecture.
The article explains Java's Object class as the root of all classes, details its fundamental methods such as clone, equals, hashCode, toString, finalize and getClass, illustrates shallow vs. deep copying, shows how to override equals with a Book example, and warns about using finalize for cleanup.
Understanding the lifecycle, scope, and thread characteristics of HttpServletRequest and HttpSession reveals common misuse that leads to data corruption, login state errors, and lost cart data; the article explains core differences, proper use cases, real‑world bug examples, and practical solutions such as read‑only policies, synchronization, thread‑safe collections, and Redis‑based session storage.
The article demonstrates how to replace manual JAR deployment with a dynamic hot‑deployment mechanism that loads user‑provided JARs at runtime, supporting both Spring‑managed and pure‑reflection implementations, and explains bean registration, removal, and testing procedures.
The article analyzes the public beta of Claude Agent in IntelliJ IDEA, explaining how its deep IDE integration transforms Java developers' workflow from manual code editing to AI‑driven multi‑step task execution, while highlighting new risks, team‑level usage, and practical start‑up steps.
This article presents a complete knowledge map of the AgentScope Java framework—including its core components, API quick‑reference, and a high‑frequency Q&A self‑test—to help developers understand and master multi‑agent orchestration on the JVM.
This article explains why LangChain4j is needed for advanced Java AI agents, compares its capabilities with Spring AI, walks through project setup, configuration, defining tools and memory, assembling the agent, and demonstrates a complete smart‑customer service example with testing commands.
RabbitMQ achieves consumer‑side throttling by configuring basic.qos with a prefetchCount, disabling automatic ACK, and using manual ACK so that the broker only pushes a limited number of unacknowledged messages, with detailed guidance on parameter settings, pitfalls, and code examples.
SpaceX’s $60 billion acquisition of Cursor reveals a turning point where AI programming is evolving from merely generating code snippets to orchestrating the entire software development lifecycle—handling requirements analysis, environment setup, testing, and pull‑request creation—especially within complex Java projects that demand robust build and test pipelines.
The article examines the limitations of using UUIDs for distributed unique identifiers, compares common alternatives such as database auto‑increment and Redis, and then details the Snowflake algorithm’s structure, implementation, advantages, and drawbacks for high‑performance ID generation.
This benchmark measures the peak memory consumption of one, ten‑thousand, one‑hundred‑thousand and one‑million concurrent tasks in Rust, Go, Java, C#, Node.js, Python and Elixir, revealing surprising differences such as Go using far more memory than Rust and .NET showing unusually low usage.
This article introduces the Composite design pattern, explains its purpose of treating leaf and container objects uniformly, shows typical tree‑structured use cases, and provides a complete Java implementation with abstract component, leaf, composite, and a test demo.
This tutorial explains how the super keyword invokes a superclass constructor—both no‑argument and parameterized—illustrates constructor chaining across inheritance hierarchies with concrete Java code examples, and highlights compilation errors when a matching superclass constructor is missing.
This article introduces the open‑source spring‑response‑envelope library for Spring Boot 3, showing how a single @ResponseEnvelope annotation can automatically wrap controller results in a standard JSON structure, add metadata, handle errors, expose metrics, and reduce boilerplate code by about 30%.
The article explains AgentScope 2.0’s “agent‑as‑tool” philosophy, showing how a Router agent can dynamically delegate tasks to specialist ReActAgents via @Tool methods, and how HarnessAgent’s Subagent feature enables long‑running, user‑direct interactions, with concrete Java code illustrating both patterns.
This article explains how Function Calling lets large language models invoke Java methods via Spring AI, walks through the four‑step workflow, shows declarative and programmatic tool definitions, and demonstrates a complete customer‑service chatbot with code examples and best‑practice guidelines.
This article explains how to integrate large language models into enterprise Java microservices using Spring 7.0 and Spring AI, covering architectural layers, design principles, code structure, resilience, observability, and a step‑by‑step production checklist to turn AI capabilities into a maintainable, high‑throughput service.
This article walks through the core features of PowerJob, compares it with other Java job schedulers, and provides step‑by‑step instructions for installing, configuring, and creating tasks using both Docker and jar deployments, complete with code samples and UI screenshots.
This article walks through using the Yauaa library in Spring Boot 3.5.0 to extract detailed client‑side information—device class, operating system, and browser—from the User‑Agent header, covering basic bean setup, advanced cache configuration, field selection, and device‑based routing examples.
This article explains why telescoping constructors and JavaBean setters are problematic, demonstrates a hand‑written Builder implementation based on Effective Java, shows how Lombok @Builder simplifies code, and warns about two common Lombok pitfalls—default values and inheritance—while offering practical solutions.
At 3 am a production server saw Full GC spike from once a day to ten times a minute because a ThreadLocal holding a large object was never removed, leading to a memory leak that almost took the machine down, and the article explains the root cause, internal mechanics, and remediation strategies.
The open‑source AgentScope Java framework now ships with version 2.0, introducing HarnessAgent for long‑running tasks, a Workspace‑based persistence layer, enterprise‑grade multi‑tenant isolation, streaming events, and a refactored middleware model, all illustrated with runnable Java examples and a concise feature table.
This tutorial demonstrates how the super keyword lets a subclass invoke overridden methods and access shadowed fields in its superclass, providing step‑by‑step Java code examples, execution results, and explanations of the underlying inheritance mechanics.
This article explains how HarnessAgent extends a ReActAgent with engineering features such as middleware hooks, workspace sandboxing, context compression, and model fault‑tolerance to make AI agents reliable for long‑running production deployments.
The article provides a detailed analysis of three popular Java scheduling solutions—@Scheduled, Quartz, and XXL‑Job—highlighting their core features, differences, common pitfalls, and practical advice for selecting the right tool based on project requirements and deployment scenarios.
The article explains how off‑heap memory and mmap enable zero‑copy I/O for high‑performance Linux services, but because the JVM does not manage it, careless allocation or missing releases can cause off‑heap memory leaks that lead to OOM, and it provides concrete detection and mitigation techniques.
FastUtil, an open‑source library maintained by Sebastiano Vigna, offers type‑specialized Java collections that are typically 2–5× faster and use 40–70% less memory than JDK equivalents, and this article provides detailed benchmarks, a cheat‑sheet of core types, production‑ready code snippets, Maven/Gradle setup, and a checklist of common pitfalls to help developers adopt FastUtil safely and efficiently.
This article explains how to equip a Java application with Retrieval‑Augmented Generation (RAG) so large language models can access private PDFs, Word files, and internal documents, covering the core architecture, two implementation paths using LangChain4j and Spring AI, vector‑store options, and practical tuning techniques.
The article details how to construct an enterprise‑level Retrieval‑Augmented Generation (RAG) knowledge‑base for the insurance sector, covering architecture, dual‑service Java + Python design, tech selections such as MiMo LLM, BGE‑M3 embeddings, hybrid search, performance‑tuned streaming, permission models, and lessons learned.
This article walks through a complete RAG pipeline, identifying common pitfalls from document preprocessing to prompt construction, and provides concrete Python and Java examples, chunking strategies, embedding tweaks, hybrid retrieval, reranking, advanced techniques, and evaluation methods to reliably double retrieval accuracy.
The note explains Java's variable hiding where a subclass field with the same name as a superclass field conceals the original, demonstrates it with a Father‑Son example, shows the output, and warns that such practice can hurt code readability.
Learn how to replace sprawling if‑else logic in payment gateways and SaaS platforms by combining the Strategy and Factory patterns, with concrete Spring Boot examples, step‑by‑step code, and a progression from simple to abstract factories that enforce the Open‑Closed principle.
OKHttpUtil wraps Square's OkHttp library to provide a lightweight, easy‑to‑use HTTP client for Java and Kotlin, automatically handling HTTP/HTTPS detection, cookies, redirects, gzip, proxy and User‑Agent configuration, with Maven coordinates, Spring Boot starter support and concise code examples for GET, POST, file upload, download and custom API wrappers.
The article explains the concept of delayed tasks versus scheduled tasks and evaluates several backend solutions—including database polling with Quartz, JDK DelayQueue, Netty's HashedWheelTimer, Redis ZSET, Redis key‑space notifications, and RabbitMQ delayed queues—detailing their implementations, code samples, advantages, and drawbacks for automatically cancelling orders that remain unpaid for a set period.
This tutorial explains why a private Maven repository is useful for Java teams, walks through downloading and installing Nexus on Linux, configuring repositories, managing firewall rules, setting up anonymous access, and publishing and retrieving artifacts using Maven settings and commands.
This article explores Spring AI's core design patterns, advanced ChatClient usage, dynamic PromptTemplate creation, few‑shot prompting, structured output parsing, and declarative function calling with @Tool annotations, providing code examples, advisor mechanisms, and testing tips for Java developers.
This article introduces OKHttpUtil, a lightweight wrapper around OkHttp that lets Java developers perform HTTP GET, POST, file upload, download and Spring Boot integration with a single line of code, while offering features such as automatic HTTPS detection, cookie handling, proxy and GZIP support.
The article explains Java pooling techniques for high‑concurrency scenarios, introduces Apache Commons Pool 2, demonstrates how to configure dependencies, implement a PooledObjectFactory, create custom eviction policies and statistics, and shows a complete runnable example that highlights resource reuse and performance gains.
This article introduces the Bridge design pattern, explains its purpose of separating two independent dimensions to reduce class explosion, provides practical real‑world examples, and walks through a complete Java implementation with interface, abstract bridge, concrete classes, and a test driver.
The article explains how Spring AI’s recursive advisors enable dynamic tool discovery, replacing the traditional all‑tools‑in‑prompt approach, thereby reducing token consumption by 34%‑64% while preserving access to hundreds of tools, and provides benchmark data, code examples, and configurable search strategies.
This tutorial walks Java backend developers through the mature Java LLM ecosystem, comparing frameworks like Spring AI and LangChain4j, and demonstrates step‑by‑step how to create a Spring Boot application with a chat endpoint, streaming responses, and dynamic model switching among OpenAI, Tongyi Qwen, and Ollama.
The article breaks down the ReAct reasoning‑acting loop that powers AgentScope's ReActAgent, details its builder parameters, and compares the synchronous call() method with the streaming stream() approach, showing when each should be used for backend processing or interactive UI.
AgentScope Java 2.0, released in June 2026, adds native distributed deployment, multi‑tenant isolation, fine‑grained permission control, workspace‑driven state management, middleware extensibility, model fault‑tolerance and event‑stream APIs, turning demo‑only agents into production‑ready, observable, and secure AI services for enterprise Java environments.
This article breaks down AgentScope Java's five fundamental components—Message, Agent, Model, Memory, and Tool—explaining their roles, structures, code examples, provider switching, tool definition, and state management, while highlighting concurrency pitfalls and persistence options.
The article explains how Salesforce’s $3.6 billion acquisition of Fin signals a shift from simple chatbot answers to AI agents that execute end‑to‑end business actions, and why Java/Spring Boot developers must expose secure, auditable services rather than merely wrapping large‑model APIs.
This guide walks through Redis Sentinel’s architecture, explains subjective and objective down states, details the leader election and failover workflow, shows step‑by‑step configuration of a three‑node Sentinel cluster, client integration in Python and Java, and provides best‑practice recommendations, monitoring metrics, and troubleshooting tips.
This article walks Java developers through setting up AgentScope Java 2.0, explains the core ReActAgent and HarnessAgent classes, shows how to configure a DashScope model key, and provides a complete Maven project and code example that streams a typed‑out response from the AI agent.
This article introduces the Prototype design pattern, explains its purpose of cloning existing objects to avoid costly construction, illustrates practical scenarios such as product templates and game asset generation, provides a complete Java shallow‑copy example, and highlights common pitfalls and differences from the Factory pattern.
A production outage caused by a Java Stream pipeline processing one million orders revealed massive memory overhead and CPU‑bound garbage collection, prompting a benchmark that showed a handcrafted for‑loop to be up to twenty times faster and far more memory‑efficient.
Spring AI 2.0 reaches GA, offering a production‑grade, Java‑first AI development path tightly integrated with Spring Boot 4.x, Spring Framework 7.0, and the Model Context Protocol, while introducing upgraded agent tooling, Jackson 3, JSpecify annotations, and streamlined provider SDKs.
This article dissects Spring’s singleton bean creation process, explaining the three‑level cache system, the doGetBean and doCreateBean workflows, circular‑dependency handling, proxy generation timing, and common pitfalls such as multithreaded duplicate creation and hot‑deployment cache issues.
Project Valhalla's JEP 401, introducing value classes and objects, merges into the OpenJDK mainline as a preview feature in JDK 28, involving 1,816 files and over 197,000 new lines, with a cautious rollout timeline and notable design trade‑offs for Java performance.
The article explains how HashMap can enter an infinite loop, lose data, or corrupt entries when accessed concurrently, illustrates the root causes with JDK 1.7 and 1.8 source code, compares alternative thread‑safe maps, and shows how to answer this classic interview question.
As AI coding tools like Claude Code, Cursor and Codex can automatically edit multiple files, run commands, and modify production configurations in Spring Boot projects, the real danger lies in the lack of automated gatekeeping that enforces engineering rules and prevents unintended side effects.
The article explains why indiscriminate use of the Java new operator leads to duplicated configuration, hidden complexity, and performance problems, and demonstrates how Factory, Builder, Object‑Pool, and Prototype patterns—illustrated with Spring Boot 3.5.0 code—provide clean, maintainable alternatives that distinguish junior from senior developers.
This article introduces the Builder design pattern, illustrates its concept with everyday analogies like milk‑tea making, and provides a complete Java example that assembles a computer through step‑by‑step builders, followed by a summary of typical business use cases and a tip on avoiding confusion with the Factory pattern.
This article provides a thorough, image‑rich overview of Java concurrency, covering the differences between concurrency and parallelism, thread lifecycle states, various ways to create threads, thread‑pool design and workflow, the Java Memory Model, and essential JUC utilities, all illustrated with code snippets and diagrams.
The article compares several ways of inserting 300,000 MySQL rows—single‑row loops, an un‑batched MyBatis attempt that hits the max_allowed_packet limit, and a tuned batch strategy that commits every 1,000 rows—showing how the optimized batch reduces the runtime from hours to just 13 seconds and summarizing best‑practice tips.
The article explains how the Abstract Factory pattern creates whole families of related objects—contrasting it with the Factory Method—illustrates practical scenarios such as phone accessories, UI themes, and payment suites, provides step‑by‑step Java code, lists common use cases, and discusses its limitations.
This article explains how to prevent out‑of‑memory errors when importing huge Excel files in Java by using the open‑source excel‑streaming‑reader library, showing Maven setup, streaming code examples, memory‑saving configurations for shared strings and comments, and tips for handling extremely large workbooks.
An experienced architect compares RabbitMQ and Kafka across core protocols, storage, replication, consumption semantics, and real‑world production designs, offering Java 17/Spring Boot code, cloud‑native deployment tips, observability, and a decision framework that matches messaging patterns to business requirements.
The article explains how to implement a pure‑Java DOCX‑to‑PDF conversion service in Spring Boot with docx4j, compares it against alternatives such as Apache POI+iText, LibreOffice+JODConverter and Aspose.Words, and provides step‑by‑step code for Maven dependencies, a utility class with font mapping to avoid Chinese garbling, a controller endpoint, and platform‑specific font‑installation fixes for Windows and Linux.
