# legacy code Published articles for legacy code. This is one page of public article previews, not the complete archive. Follow Next page to continue. Summaries are not the original full articles. ## How to Migrate a Legacy Monolith Incrementally Without a Big-Bang Rewrite DevFeed: [How to Migrate a Legacy Monolith Incrementally Without a Big-Bang Rewrite]() Original publisher: [Read original article]() Author: Hugo Teijiz Published: 2026-09-17T23:27:03Z Content type: tutorial Language: en Sources: [freeCodeCamp Programming Tutorials: Python, JavaScript, Git & More]() Topics: [Legacy Modernization](), [migration](), [Refactoring](), [Testing](), [Integration testing](), [observability](), [Routing (disambiguation)](), [Transactions](), [TypeScript](), [API](), [service](), [Dependency injection]() Tags: [artificial-intelligence](), [how-to](), [incremental](), [integration-testing](), [legacy](), [legacy-code](), [migrate](), [migration](), [monolith](), [refactoring](), [rewrite](), [routing](), [software-architecture](), [transactions]() ### AI overview A tutorial on migrating a legacy monolith incrementally by moving one business capability at a time. It covers characterization tests, boundaries between legacy and new code, parallel implementations, progressive traffic, observability, rollback paths, data ownership, and removing migrated behavior. ### Source excerpt Large legacy migrations often fail long before the final cutover. The failure usually starts when the migration is framed as a single event. Move the application. Move the database. Move all the users ## Using acceptance tests to catch regression bugs in legacy code before production DevFeed: [Using acceptance tests to catch regression bugs in legacy code before production]() Original publisher: [Read original article]() Author: Valentina Jemuović Published: 2026-09-16T07:33:58Z Content type: tutorial Language: en Sources: [Optivem Journal]() Topics: [Testing](), [Requirements](), [legacy]() Tags: [automated](), [bugs](), [e2e](), [legacy-code](), [regression](), [requirements](), [testing](), [ui](), [unit-tests]() ### AI overview This hands-on article explains why automated unit and end-to-end tests may still allow production bugs in legacy code. It presents acceptance test-driven development (ATDD), where requirements and tests describe the same observable behavior, making coverage clearer and reducing dependence on UI steps. ### Source excerpt You automated, and manual regression testing is still there. Those two facts have the same cause. ## How to Use Differential Testing During a Legacy Migration DevFeed: [How to Use Differential Testing During a Legacy Migration]() Original publisher: [Read original article]() Author: Hugo Teijiz Published: 2026-09-14T16:25:50Z Content type: tutorial Language: en Sources: [freeCodeCamp Programming Tutorials: Python, JavaScript, Git & More]() Topics: [migration](), [Testing](), [TypeScript](), [Integration testing](), [API](), [observability](), [Artificial Intelligence]() Tags: [ai](), [api](), [architecture](), [artificial-intelligence](), [code](), [how-to](), [integration](), [legacy-code](), [legacy-modernization](), [migration](), [modernization](), [observability](), [software-architecture](), [software-testing](), [testing](), [tests](), [tutorial](), [typescript]() ### AI overview This tutorial explains how to use differential testing during a legacy migration by running old and new implementations with identical inputs and comparing their behavior. It covers equivalence rules, output normalization, nondeterministic values, errors, side effects, automated testing, mismatch analysis, production shadow traffic, and using AI to classify divergences without allowing it to determine correctness. ### Source excerpt The most dangerous moment in a legacy migration isn't necessarily when you start writing the new implementation. It's when the new implementation looks finished. The code compiles, the tests pass, the ## How a Tech Lead Encouraged Testing in Legacy Code DevFeed: [How a Tech Lead Encouraged Testing in Legacy Code]() Original publisher: [Read original article]() Author: Valentina Jemuović Published: 2026-08-04T06:02:15Z Content type: opinion Language: en Sources: [Optivem Journal]() Topics: [Test-driven development](), [legacy](), [clean-code](), [Template](), [Software Engineering]() Tags: [clean-code](), [legacy-code](), [tdd](), [tech-lead](), [training](), [unit-tests]() ### AI overview This opinion article recounts how an engineering leader struggled to introduce testing and clean-code practices across multiple companies. As a Tech Lead, the author created a testable Clean Architecture template, recruited developers who valued quality, built an initial module, and trained the team to use the approach. ### Source excerpt "We don't have time to write the code twice." ## Broken Systems Don't Need More Developers DevFeed: [Broken Systems Don't Need More Developers]() Original publisher: [Read original article]() Author: Valentina Jemuović Published: 2026-07-14T09:12:34Z Content type: opinion Language: en Sources: [Optivem Journal]() Topics: [systems](), [legacy](), [Back end](), [Test-driven development]() Tags: [architecture](), [code-reviews](), [developers](), [engineering](), [legacy](), [legacy-code](), [meetings](), [merge](), [onboarding]() ### AI overview Adding developers to a tightly coupled legacy system may slow progress because onboarding, interruptions, meetings, code reviews, and merge conflicts increase. The article argues that architecture, rather than team size, is the main bottleneck. ### Source excerpt If four developers aren't delivering fast enough, why not make it eight? ## TDD in Legacy Code - Maintainable Component Tests - Backend DevFeed: [TDD in Legacy Code - Maintainable Component Tests - Backend]() Original publisher: [Read original article]() Author: Valentina Jemuović Published: 2026-07-02T06:02:41Z Content type: tutorial Language: en Sources: [Optivem Journal]() Topics: [Back end](), [Test-driven development](), [legacy]() Tags: [api](), [backend](), [component](), [erp](), [legacy](), [legacy-code](), [refactor](), [tdd](), [tests]() ### AI overview A tutorial on refactoring brittle backend component tests that are coupled to a backend API and ERP system, with the goal of making them more maintainable. ### Source excerpt Many Backend Teams write unmaintainable Backend Component Tests - coupled to the Backend API and ERP. I'll show you how to refactor these brittle tests. ## Why Legacy Code Turns Small Changes Into Multi-Day Firefighting DevFeed: [Why Legacy Code Turns Small Changes Into Multi-Day Firefighting]() Original publisher: [Read original article]() Author: Valentina Jemuović Published: 2026-06-30T06:02:36Z Content type: opinion Language: en Sources: [Optivem Journal]() Topics: [legacy](), [Test-driven development](), [Development](), [Software]() Tags: [dev](), [engineering](), [legacy-code](), [tdd]() ### AI overview This commentary examines how legacy code can turn a small change into days of investigation and risk. It argues that tangled dependencies, missing tests, and outdated code prevent senior developers from improving architecture and make routine maintenance frustrating. ### Source excerpt The field took twenty minutes. Everything around it took three days. ## Joining forces to modernize legacy software DevFeed: [Joining forces to modernize legacy software]() Original publisher: [Read original article]() Author: Mary Louise Stewart Published: 2026-05-14T08:00:00Z Content type: release Language: en Sources: [Federico Tomassetti]() Topics: [Software](), [Reverse Engineering](), [Refactoring](), [Code generation](), [interoperability](), [AI-assisted coding]() Tags: [code-generation](), [interoperability](), [legacy-code](), [legacy-modernization](), [migration](), [model-driven-development](), [modernization](), [parsing](), [refactoring](), [reverse-engineering](), [software](), [transpilers]() ### AI overview Strumenta and Metadev announced a collaboration to modernize legacy software. Strumenta contributes code analysis, extraction, and transformation capabilities, while Metadev contributes modeling, AI integration, and code generation. Their approach uses LionWeb models as an intermediate representation between legacy code and modernized systems. ### Source excerpt Strumenta and Metadev Join Forces to Modernize Legacy Software A collaboration combining Strumenta's expertise in code analysis, extraction, and transformation with Metadev's capabilities in modeling, artificial intelligence, and code generation from models. Torino/Seville, May 14, 2026 -- Strumenta S.r.l. and Metadev S.L. have reached a collaboration agreement to offer a joint approach to Modernizing Legacy [...] The post Joining forces to modernize legacy software appeared first on Federico Tomassetti. ## From Prompt to Payment: How Developers Ship Billing in 2026 DevFeed: [From Prompt to Payment: How Developers Ship Billing in 2026]() Original publisher: [Read original article]() Author: Ayush Agarwal Published: 2026-04-11T00:00:00Z Content type: article Language: en Sources: [Dodo Payments Blog]() Topics: [Artificial Intelligence](), [SDKs](), [Software as a service]() Tags: [2026](), [agentic](), [ai](), [authentication](), [billing](), [checkout](), [developer-tools](), [developers](), [integration](), [legacy-code](), [prompt](), [sdk](), [testing]() ### AI overview The article describes a shift from manual billing integrations to prompt-driven billing agents. It says these agents can generate code, configure billing systems, connect events, and address edge cases, reducing the described integration timeline from weeks to hours. ### Source excerpt Developers in 2026 are shipping billing through AI prompts instead of manual SDK wiring. Learn how agentic billing tools like Sentra compress weeks of integration into hours. ## Refining SQL Data Models Without Breaking Legacy Code DevFeed: [Refining SQL Data Models Without Breaking Legacy Code]() Original publisher: [Read original article]() Author: Hillel Wayne Published: 2026-01-20T17:49:07Z Content type: article Language: en Sources: [Newsletter feed for Hillel Wayne's Newsletter]() Topics: [SQL](), [Databases](), [legacy]() Tags: [database](), [event-sourcing](), [legacy-code](), [sql](), [sql-database]() ### AI overview This article explains how refinement mappings can support SQL schema changes while preserving compatibility with existing code. It applies the approach to migrating a boolean column to a timestamp, then to an event-sourcing-like model, and examines how mutability constraints affect whether the refinement remains valid. ### Source excerpt Imagine we have a SQL database with a user table, and users have a non-nullable is_activated boolean column. Having read That Boolean Should Probably Be Something else, you decide to migrate it to a nullable activated_at column. You can change any of the SQL queries that read/update the user table but not any of the code that uses the results of these queries. Can we make this change in a way that preserves all external properties? Yes. If an update would set is_activated to true, instead set it to the current date. Now define the refinement mapping that takes a new_user and returns an old_user. All columns will be unchanged except is_activated, which will be f(new_user).is_activated = if new_user.activated_at == NULL then FALSE else TRUE Now new code can use new_user directly while legacy code can use f(new_user) instead, which will behave indistinguishably from the old_user. A little more time passes and you decide to switch to an event sourcing-like model. So instead of an activated_at column, you have a user_events table, where every record is (user_id, timestamp, event). So adding an activate event will activate the user, adding a deactivate event will deactivate the user. Once again, we can update the queries but not any of the code that uses the results of these queries. Can we make a change that preserves all external properties? Yes. If an update would change is_activated, instead have it add an appropriate record to the event table. Now, define the refinement mapping that takes newer_user and returns new_user. The activated_at field will be computed like this: g(newer_user).activated_at = # last_activated_event let lae = newer_user.events .filter(event = "activate" | "deactivate") .last, in if lae.event == "activate" then lae.timestamp else NULL Now new code can use newer_user directly while old code can use g(newer_user) and the really old code can use f(g(newer_user)). Mutability constraints I said "these preserve all external properties" and that was a ## Out with the Old, In with the New: A Guide to Application Upkeep DevFeed: [Out with the Old, In with the New: A Guide to Application Upkeep]() Original publisher: [Read original article]() Author: Andres Sacco Published: 2025-12-20T03:08:59Z Content type: tutorial Language: en Sources: [Java Advent Calendar]() Topics: [Java](), [migration](), [Spring Boot](), [Microservice](), [Vulnerabilities](), [Security]() Tags: [2025](), [automatic](), [guide](), [java](), [legacy-application](), [legacy-code](), [maintainability](), [microservices](), [migration](), [rewrite](), [security](), [spring](), [spring-boot]() ### AI overview This guide explains why upgrading Java or Spring Boot applications involves more than changing a version number. It discusses migration challenges, legacy code, differing versions across microservices, and risks from outdated software, including security, compatibility, stability, and maintainability concerns. ### Source excerpt Migrating an existing application to a new version of Java or a framework such as Spring Boot involves much more than simply updating a version number in a file. Each new release of a library or language brings new features, deprecations, behavioral changes, and sometimes complete API redesigns. When legacy code is involved, these upgrades [...] The post Out with the Old, In with the New: A Guide to Application Upkeep appeared first on JVM Advent. ## Breathing New Life into Legacy Systems. The Artisan of the Day Is Elena Cañete. DevFeed: [Breathing New Life into Legacy Systems. The Artisan of the Day Is Elena Cañete.]() Original publisher: [Read original article]() Author: Ana Tavares Published: 2025-09-29T14:05:51Z Content type: article Language: en Sources: [Laravel Blog]() Topics: [Laravel](), [PHP](), [Microservices](), [Development](), [Architecture & Design]() Tags: [architecture](), [developer](), [laravel](), [legacy](), [legacy-code](), [microservices](), [microservices-architecture](), [php]() ### AI overview Elena Cañete specializes in modernizing legacy systems. Her work includes rebuilding vanilla PHP ERP systems with Laravel, migrating a TYPO3 monolith to a Laravel-based microservices architecture, and modernizing ERP and API systems for scalable, future-proof solutions. ### Source excerpt Elena Cañete modernizes legacy systems with Laravel, turning clunky code into scalable solutions while inspiring developers to embrace tough projects. ## How To Refactor Legacy Code DevFeed: [How To Refactor Legacy Code]() Original publisher: [Read original article]() Author: Daniel Moka Published: 2025-04-12T05:01:26Z Content type: tutorial Language: en Sources: [Craft Better Software]() Topics: [Refactoring](), [Testing](), [Dependency injection](), [Test coverage](), [Mocking]() Tags: [dependency-injection](), [how-to](), [legacy-code](), [refactor](), [refactoring](), [testing](), [tests]() ### AI overview A six-step strategy for refactoring legacy code by breaking dependencies, using characterization and other testing techniques, achieving test coverage, and then changing the code. ### Source excerpt The art of making your code testable, testing it effectively, and refactoring it like a pro ## Dependency Injection in Legacy Code DevFeed: [Dependency Injection in Legacy Code]() Original publisher: [Read original article]() Author: blundell Published: 2023-10-19T12:26:59Z Content type: tutorial Language: en Sources: [Blundell]() Topics: [Dependency injection](), [Dagger](), [Android](), [android-development](), [legacy](), [Development]() Tags: [android](), [android-development](), [dagger](), [dependency-injection](), [development](), [intermediate](), [legacy](), [legacy-code](), [reference]() ### AI overview This tutorial explains how to use Dagger and Hilt entry points to inject dependencies into Android legacy singletons and other classes that are not managed by the current architecture. It focuses on cases where the legacy code can access a Context and describes defining an entry-point interface for required bindings. ### Source excerpt This post explains how you can inject dependencies into Android legacy singletons, or any classes that aren't conforming to your current Android architecture, using Dagger & Hilt. I'll cut straight to the chase, if you have a reference to Context, (which you usually always do in spaghetti legacy code) then you can use your normal [...] The post Dependency Injection in Legacy Code first appeared on Blundell. ## Effective ways to contribute in a new codebase as an onboarding iOS Engineer DevFeed: [Effective ways to contribute in a new codebase as an onboarding iOS Engineer]() Original publisher: [Read original article]() Author: Hakeem Musse Published: 2023-04-11T20:35:32Z Content type: tutorial Language: en Sources: [Making Meetup - Medium]() Topics: [iOS](), [Documentation](), [implementation](), [Xcode](), [Code](), [legacy](), [A/B Testing](), [Framework]() Tags: [a-b-testing](), [code](), [dependencies](), [documentation](), [engineering](), [ios](), [legacy-code](), [mobile](), [onboarding](), [tips](), [xcode]() ### AI overview An iOS engineer at Meetup shares onboarding practices for contributing to an existing codebase. Using the re-platforming of an A/B testing Experiment feature as an example, the article emphasizes reading documentation, understanding architecture and dependencies, and resolving issues when modularizing legacy code. ### Source excerpt Photo by Aron Visuals on Unsplash For most engineers, joining a new organization means having to onboard to some existing codebase. The larger a codebase, the more complicated it can be to navigate for new engineers, which can be overwhelming to start contributing code. As an iOS Engineer at Meetup, I experienced this firsthand when onboarding. This blog post focuses on some tips I've learned from my experiences contributing to Meetup's iOS codebase when I first onboarded. To illustrate these practices, let's look at an example of a task I worked on. The task My task was to re-platform our Experiment feature in the iOS app, which allows us to conduct A/B testing on new features. At the time, this feature was located in Meetup's legacy codebase and part of the task was to move this code into its own module. The acceptance criteria for this task was to make it so any engineer can import the standalone feature and use it without having to reference legacy code. When I began this task, I had some knowledge of where I can start working, so like any eager engineer, I dove right in! On the surface, re-platforming is essentially moving over files and implementation to a modularized framework. I thought, "how hard can this be, right?" I started ⌘+ C'ing like never before! Files were being copied at the speed of light. We were taking flight! I couldn't wait for the reaction of my peers: "Damn, Hakeem, you did this that quickly?" However, not too far into the work, I was hit with about 100+ Xcode errors when trying to compile. I could faintly hear Xcode laughing at me. This leads me to tip number one... Reading Documentation This underestimation was a sign for me that I had to go back to square one and read up on how this feature is architected. Indeed, reading the documentation unveiled nuggets of information on how to re-platform that I didn't realize. More importantly, reading documentation gave a high level picture of how individual components work together. So, I tried agai ## Cooking Effective Code Reviews. DevFeed: [Cooking Effective Code Reviews.]() Original publisher: [Read original article]() Author: Fernando Cejas (me@fernandocejas.com) Published: 2021-08-04T00:00:00Z Content type: tutorial Language: en Sources: [Fernando Cejas Blog]() Topics: [Code review](), [pull-requests](), [Development](), [engineering-culture](), [decision-making]() Tags: [android](), [code-quality](), [code-review](), [code-reviews](), [culture](), [development](), [engineering](), [infrastructure](), [ios](), [java](), [kotlin](), [legacy-code](), [linux](), [open-source](), [processes](), [programming](), [python](), [rust](), [scala](), [software](), [software-development](), [structured](), [team](), [tech-debt](), [web-development]() ### AI overview A tutorial on making pull request code reviews more effective through a structured process. It discusses their role in code quality, documentation, collaboration, engineering culture, and keeping reviews small enough to manage. ### Source excerpt **Reviewing code (PRs) is not an easy task**, so in this post I will share **tips and tricks** on how your code reviews can better contribute to **code quality**, **be more effective and increase team morale** by following a structured and organized process. **Let's jump in!** ## Rethinking the Next-gen Analytics Web App at trivago DevFeed: [Rethinking the Next-gen Analytics Web App at trivago]() Original publisher: [Read original article]() Author: Daw Chih Liou Published: 2021-02-09T00:00:00Z Content type: article Language: en Sources: [Trivago]() Topics: [web applications](), [Front end](), [jQuery](), [legacy](), [A/B Testing](), [User Experience]() Tags: [a-b-testing](), [analytics](), [backend](), [frontend](), [legacy-application](), [legacy-code](), [user-experience](), [web]() ### AI overview trivago's Frontend Engineering team describes rebuilding its nearly decade-old in-house Business Intelligence web application for analytics and A/B testing. The article explains the legacy system's maintenance, testing, data-flow, UI, and design-system challenges, and reports that the revamped application became more reliable, user-friendly, and scalable while the legacy application was retired. ### Source excerpt After almost a decade, we decided to rebuild our in-house Business Intelligence web application to better support the organization. It is always challenging to replace software with a long history and a high degree of complexity. Nevertheless, we successfully completed the project because we fundamentally challenged and re-thought all aspects of the project. ## 5 Tips for Managing Remote Engineers & Development - Touchlab DevFeed: [5 Tips for Managing Remote Engineers & Development - Touchlab]() Original publisher: [Read original article]() Published: 2020-03-20T16:56:42Z Content type: tutorial Language: en Sources: [Touchlab | Enterprise Mobile Innovation & Development]() Topics: [Development](), [Software Engineering](), [Mobile](), [code productivity](), [Tech Debt]() Tags: [business](), [covid-19](), [development](), [legacy-code](), [mental-health](), [mobile-engineering](), [productivity](), [refactoring](), [remote](), [software-development](), [tech-debt](), [thoughts](), [work-from-home]() ### AI overview Touchlab shares five practices for managing remote software development during the COVID-19 pandemic: establish a remote-work cadence, document relevant one-to-one conversations, reduce unnecessary interruptions, prioritize outcomes over activity, and use downtime to reduce technical debt through legacy-code refactoring. ### Source excerpt Touchlab is a remote-first software development firm. With COVID-19 forcing 100% WFH policies, we're sharing 5 tips for managing remote software dev. ## Technical Debt and Legacy Code: Techniques for Improving Code Health DevFeed: [Technical Debt and Legacy Code: Techniques for Improving Code Health]() Original publisher: [Read original article]() Author: Fernando Cejas (me@fernandocejas.com) Published: 2020-03-13T00:00:00Z Content type: opinion Language: en Sources: [Fernando Cejas Blog]() Topics: [Software Engineering](), [legacy](), [maintenance](), [Testing](), [Unit testing]() Tags: [android](), [clean-code](), [culture](), [development](), [engineering](), [how-to](), [infrastructure](), [ios](), [java](), [kotlin](), [legacy-code](), [linux](), [maintenance](), [open-source](), [programming](), [python](), [rust](), [scala](), [software](), [software-development](), [strategies](), [technical](), [unit-testing](), [web-development]() ### AI overview This article examines technical debt and legacy code in software projects, defines legacy code as code without tests, and discusses techniques and strategies for assessing and addressing code health and maintenance challenges. ### Source excerpt As **Software Engineers** we know that **Technical Debt** and **Legacy Code** are familiar concepts we have to live with. **Code healthiness and maintenance are challenging**, so let's dive into **tips and techniques on how to effectively address this problem.** ## Technical Debt and Legacy Code: Techniques for Improving Code Health DevFeed: [Technical Debt and Legacy Code: Techniques for Improving Code Health]() Original publisher: [Read original article]() Author: Fernando Cejas (me@fernandocejas.com) Published: 2020-03-13T00:00:00Z Content type: opinion Language: en Sources: [Fernando Cejas Blog]() Topics: [Software Engineering](), [legacy](), [maintenance](), [Unit testing]() Tags: [android](), [culture](), [development](), [engineering](), [infrastructure](), [ios](), [java](), [kotlin](), [legacy-code](), [linux](), [maintenance](), [open-source](), [programming](), [python](), [rust](), [scala](), [software](), [software-development](), [technical](), [tips](), [unit-testing](), [web-development]() ### AI overview The article discusses technical debt, legacy code, and software project health. It introduces legacy code as code without tests and explores techniques and strategies for measuring and addressing these maintenance challenges. ### Source excerpt As **Software Engineers** we know that **Technical Debt** and **Legacy Code** are familiar concepts we have to live with. **Code healthiness and maintenance are challenging**, so let's dive into **tips and techniques on how to effectively address this problem.** ## Five tips to get your code base in shape DevFeed: [Five tips to get your code base in shape]() Original publisher: [Read original article]() Author: info@jeroenmols.com (Jeroen Mols) Published: 2019-02-20T00:00:00Z Content type: tutorial Language: en Sources: [Jeroen Mols]() Topics: [Code](), [legacy](), [Development](), [test](), [App]() Tags: [architecture](), [blogs](), [bugs](), [code](), [development](), [legacy](), [legacy-code](), [refactor](), [refactoring](), [rewrite](), [software-engineering](), [test](), [tips]() ### AI overview This tutorial offers five tips for improving a legacy codebase. It advises against rewriting everything, emphasizes frequent releases and testing, and discusses the risks of complexity, insufficient testing, bugs, and delayed user value. ### Source excerpt Are you living the dream? Is your code so clean it makes your eyes just tear a little? Can't think of anything you would still like to refactor? ## Kotlin-Java Interop Can Cause Recursive Property Calls DevFeed: [Kotlin-Java Interop Can Cause Recursive Property Calls]() Original publisher: [Read original article]() Author: info@jeroenmols.com (Jeroen Mols) Published: 2018-11-01T00:00:00Z Content type: tutorial Language: en Sources: [Jeroen Mols]() Topics: [Kotlin](), [Java](), [Android Studio]() Tags: [android-studio](), [blogs](), [java](), [kotlin](), [legacy](), [legacy-code](), [puzzle](), [recursion](), [stackoverflow]() ### AI overview This article explains how Kotlin-Java interop can cause a property access to call itself recursively when inheriting from a Java class. It examines the resulting bytecode and notes that Android Studio can warn about the recursion. ### Source excerpt Java interop is one of the best features of the Kotlin language, yet sometimes this also can cause unforeseen issues... Puzzle # Disclaimer, the example below is a consequence of legacy code and only serves to demonstrate a Kotlin puzzler. ## Building a Data Table Component in React DevFeed: [Building a Data Table Component in React]() Original publisher: [Read original article]() Author: Amber Armstrong Published: 2018-10-17T17:30:00Z Content type: tutorial Language: en Sources: [Shopify Engineering](), [Shopify Engineering - Shopify Engineering]() Topics: [React](), [Front end](), [Design system](), [Web Development](), [jQuery](), [Document Object Model (DOM)]() Tags: [design-system](), [front-end](), [legacy-code](), [react](), [react-component](), [stateful](), [stateless](), [web-development]() ### AI overview This article explains how Shopify's Polaris team built a data table component in React. It highlights reusable components, props, stateful and stateless subcomponents, lifecycle methods, DOM behavior, event-listener cleanup, and the differences from a jQuery-based approach. ### Source excerpt I'm a front-end developer at Shopify, the leading commerce platform for over 600,000 merchants across the globe. I started in web development when the industry used tables for layout (nearly 20 years ago) and have learned my way through different web frameworks and platforms as web technology evolved. ## Focus On Being Precise DevFeed: [Focus On Being Precise]() Original publisher: [Read original article]() Published: 2018-02-20T00:00:00Z Content type: opinion Language: en Sources: [William Kennedy]() Topics: [Code](), [Refactoring](), [API]() Tags: [abstraction](), [api](), [ardan-labs](), [blog](), [code](), [debugging](), [go](), [go-programming](), [golang](), [legacy-code](), [programming](), [refactor](), [refactoring](), [testing]() ### AI overview The article argues that private codebases should favor precise, clear, and efficient functions over generalized APIs and excessive abstraction. It presents refactoring and, when necessary, breaking APIs as ways to avoid legacy code, misuse, fraud, bugs, and less accurate testing and debugging. ### Source excerpt Introduction I was guided for many years to write functions that are generalized and to create layers upon layers of abstraction so things don't break as business requirements change. That the cost of breaking a function signature, for example, is expensive and something that should be avoided. Therefore, write functions that take more generic parameters or hide things in a receiver or context to be less prone to breakage. On the surface this seems like a good and reasonable idea. However, I have come to believe that this practice leads to engineering problems that I consider to be much worse than the supposed benefit. For private code bases, which is the majority of the code I work on, breaking an API should be encouraged if it will make the code base better. It's better to refactor and keep the code base clear than to head down a path of legacy code. [Next page]()