#javascript
SubscribeFeeling like boosting up your career? In this section, you'll find free JavaScript courses, tutorials, and coding lessons to help you stay up-to-date with the latest developments in the JS ecosystem and take you from basic to advanced. Dive into it, and you'll find out that the world's most popular programming language is easy to learn.
Future of Frontend Frameworks Fireside Chat
React Summit 2024
28 min
Future of Frontend Frameworks Fireside Chat
6 authors
Signals are being adopted by popular frameworks, enabling code reuse and improved tooling. While merging between frameworks is unlikely, they are learning from each other and adopting shared practices. It is important to embrace the diversity of frameworks and libraries. Instead of merging, focus on standardizing the principles behind frameworks. Consider tradeoffs and benefits when choosing a framework, and explore different technologies to learn new ideas.
JavaScript Haikus: My Adventures in Tiny Coding
JS GameDev Summit 2023
27 min
JavaScript Haikus: My Adventures in Tiny Coding
This Talk is about writing super tiny JavaScript programs, known as tiny code. It explores the concept of code golf and the use of a live editor for instant feedback. The Talk discusses various ways to share tiny code, including Twitter.net. It also covers creating graphics, games, and sound in a small space. The speaker highlights inspiring tweets and showcases examples of tiny code, including asemic writing. The future of tiny code includes new techniques, better browser support, and AI-assisted programming.
Debugging JSWatch video: Debugging JS
React Summit 2023
24 min
Debugging JS
Top ContentDebugging JavaScript is a crucial skill that is often overlooked in the industry. It is important to understand the problem, reproduce the issue, and identify the root cause. Having a variety of debugging tools and techniques, such as console methods and graphical debuggers, is beneficial. Replay is a time-traveling debugger for JavaScript that allows users to record and inspect bugs. It works with Redux, plain React, and even minified code with the help of source maps.
Scaling Up with Remix and Micro Frontends
Remix Conf Europe 2022
23 min
Scaling Up with Remix and Micro Frontends
Top ContentThis talk discusses the usage of Microfrontends in Remix and introduces the Tiny Frontend library. Kazoo, a used car buying platform, follows a domain-driven design approach and encountered issues with granular slicing. Tiny Frontend aims to solve the slicing problem and promotes type safety and compatibility of shared dependencies. The speaker demonstrates how Tiny Frontend works with server-side rendering and how Remix can consume and update components without redeploying the app. The talk also explores the usage of micro frontends and the future support for Webpack Module Federation in Remix.
Full Stack Components
Remix Conf Europe 2022
37 min
Full Stack Components
Top ContentRemixConf EU discussed full stack components and their benefits, such as marrying the backend and UI in the same file. The talk demonstrated the implementation of a combo box with search functionality using Remix and the Downshift library. It also highlighted the ease of creating resource routes in Remix and the importance of code organization and maintainability in full stack components. The speaker expressed gratitude towards the audience and discussed the future of Remix, including its acquisition by Shopify and the potential for collaboration with Hydrogen.
Webpack in 5 Years?
JSNation 2022
26 min
Webpack in 5 Years?
Top ContentIn the last 10 years, Webpack has shaped the way we develop web applications by introducing code splitting, co-locating style sheets and assets with JavaScript modules, and enabling bundling for server-side processing. Webpack's flexibility and large plugin system have also contributed to innovation in the ecosystem. The initial configuration for Webpack can be overwhelming, but it is necessary due to the complexity of modern web applications. In larger scale applications, there are performance problems in Webpack due to issues with garbage collection, leveraging multiple CPUs, and architectural limitations. Fixing problems in Webpack has trade-offs, but a rewrite could optimize architecture and fix performance issues.
Towards a Standard Library for JavaScript Runtimes
Node Congress 2022
34 min
Towards a Standard Library for JavaScript Runtimes
Top ContentThere is a need for a standard library of APIs for JavaScript runtimes, as there are currently multiple ways to perform fundamental tasks like base64 encoding. JavaScript runtimes have historically lacked a standard library, causing friction and difficulty for developers. The idea of a small core has both benefits and drawbacks, with some runtimes abusing it to limit innovation. There is a misalignment between Node and web browsers in terms of functionality and API standards. The proposal is to involve browser developers in conversations about API standardization and to create a common standard library for JavaScript runtimes.
Making JavaScript on WebAssembly Fast
JSNation Live 2021
29 min
Making JavaScript on WebAssembly Fast
Top ContentWebAssembly enables optimizing JavaScript performance for different environments by deploying the JavaScript engine as a portable WebAssembly module. By making JavaScript on WebAssembly fast, instances can be created for each request, reducing latency and security risks. Initialization and runtime phases can be improved with tools like Wiser and snapshotting, resulting in faster startup times. Optimizing JavaScript performance in WebAssembly can be achieved through techniques like ahead-of-time compilation and inline caching. WebAssembly usage is growing outside the web, offering benefits like isolation and portability. Build sizes and snapshotting in WebAssembly depend on the application, and more information can be found on the Mozilla Hacks website and Bike Reliance site.
Webdevelopment Tailored for 2024
React Summit 2024
7 min
Webdevelopment Tailored for 2024
Today's Talk covers native features in browsers, including upcoming ones and the Interop Project. Native features offer speed, compatibility, and improved debugging. Notable examples include dynamic viewport units, flexbox/grid gap, container queries, and motion path. The Interop Project ensures consistent web platform features across different browsers. Upcoming features like native CSS nesting and entry/exit animations are on the horizon.
Building a JS Engine -- For Fun!
JSNation 2024
9 min
Building a JS Engine -- For Fun!
Top ContentThe Talk discusses the basics of building a JS engine, highlighting the complexity and feature completeness of existing engines. It emphasizes the possibility of creating a simpler engine tailored to specific use cases and target audiences. The speaker suggests starting anywhere in the process and provides tips on using parser libraries, implementing runtime features, and ensuring correctness through testing. Additionally, the Talk encourages exploring JavaScript standards and engaging with the open-source community.
Testing: Do More With Less
JSNation 2024
27 min
Testing: Do More With Less
This talk focuses on practical approaches for testing Node.js applications, including the use of Dora metrics and the testing trophy strategy. It emphasizes the importance of covering critical flows with integration and end-to-end tests, while also considering the cost and speed of different test types. The speaker recommends mocking third-party services and using snapshot testing, but warns about the potential for false positives. Playwright is suggested as a preferred tool, and the importance of automated test execution is emphasized.
Peace, Love and JavaScript
Node Congress 2024
17 min
Peace, Love and JavaScript
The OpenJS Foundation supports the entire JavaScript ecosystem and thousands of open source projects. They follow a neutral nonprofit organization with separate business and technical governance to minimize drama. Rebooting governance and addressing intellectual property can also help reduce conflicts. OpenJS provides collaboration spaces and support in various areas for open source projects. They foster a collaborative environment and invite participation in their projects.
Rise of the Robots
TestJS Summit 2023
27 min
Rise of the Robots
This Talk discusses the possibility of robots taking over based on Asimov's three laws of robotics. It explores the use of automation robots for testing, including building and controlling them. The Talk also covers implementing interfaces, conducting math game challenges, and the capabilities of automation testing. It addresses questions about responsive design, camera attachment, and the future roadmap. The affordability of the setup and the potential for future automation are also discussed, along with a rapid fire Q&A session.
I Run Code From the Internet!Watch video: I Run Code From the Internet!
React Advanced Conference 2023
20 min
I Run Code From the Internet!
npm packages are unsanitized inputs from the internet that we run without much scrutiny, so we need to address the issue of malicious packages. Lavamote offers proactive runtime protections to automatically detect and mitigate threats. Lava Mode uses Hardened JavaScript to provide isolation and enforce a policy for your application's build process. The talk introduces a webpack plugin for those who don't want to use the browserify ecosystem. Lavamote's behavior is explored, showcasing how it restricts package access to certain properties. Beta testing is open to gather feedback and improve Lava Mode.
Leveraging the Event Loop for Blazing-Fast Applications!Watch video: Leveraging the Event Loop for Blazing-Fast Applications!
React Advanced Conference 2023
35 min
Leveraging the Event Loop for Blazing-Fast Applications!
This talk covers the event loop, microtask queue, and provides a live demo. JavaScript is single-threaded but can perform tasks that only a multithreaded environment can. The event loop consists of a call stack and microtask queue, which allow JavaScript to run non-blocking operations. Leveraging the microtask queue can lead to significant performance improvements in applications, such as React. However, it is important to use it correctly to avoid issues like infinite loops.
Game Development Patterns and Architectures in JavaScript
JS GameDev Summit 2023
28 min
Game Development Patterns and Architectures in JavaScript
Today's Talk covers game design and architecture, including entity component systems, game loops, and decoupling game logic from rendering. Entity component systems are popular in JavaScript game development for representing games as entities and their components as behavior on data. Game loops control the flow of the game and updating its state, with different architectures like fixed time step and variable time step. Decoupling game logic from rendering improves performance and flexibility, allowing for independent updates and easy addition of new features. Having a clear separation of concerns in game development improves performance, increases flexibility, and makes debugging easier.
Unleashing Object Proxies: Building Type-Safe Wrappers for Anything
TypeScript Congress 2023
16 min
Unleashing Object Proxies: Building Type-Safe Wrappers for Anything
Object proxies are middleware for objects that allow control over input and output. They have various use cases such as controlling data access, adding logging, and handling responses. Implementing object proxies involves transpiling calls into network requests and handling property access and method calls. Handling object proxy traps and errors involves faking object structure, logging target objects and properties, and resolving errors. Making API calls with object proxies involves defining the correct type, making backend calls, and wrapping methods to return promises. Object proxies are widely used in ORMs and RPC libraries and should be explored and experimented with.
Are the (module) types wrong?
TypeScript Congress 2023
30 min
Are the (module) types wrong?
This Talk discusses module system complexities and terminology, TypeScript and Node disagreements, and fixing TypeScript errors with the Helmet package. It also explores module resolution and type disagreements, challenges with TypeScript and Node support, and the need for improvements in popular packages.
Generating types without climbing a tree
TypeScript Congress 2023
30 min
Generating types without climbing a tree
This talk explores the challenges and benefits of generating types for APIs. The speaker discusses the need for a better client experience and the popularity of generating clients. They also explain the use of OpenAPI for generating REST API clients and the use of Cold Block Writer for code generation. The talk covers the process of defining types for parameters and responses, generating the client and request, and using the generated client. The speaker also touches on validation in production and the initial challenges with TypeScript.
Generating Typed Code
TypeScript Congress 2023
22 min
Generating Typed Code
Today, I'm going to be talking about how type generation helped reduce bugs and improve our developer experience at Rollbar. The Monolith tech stack is built primarily on Python Pyramid, a web framework that's similar to Django, Ruby on Rails, or Express. To address debugging, performance, and code navigation challenges, we migrated to a tech stack that includes TypeScript, Next.js, GraphQL, and React Query. Codegen is used to generate TypeScript code on both the server and client side, enhancing debugging, performance, and code navigation.
What is "TC39: Type Annotations" aka the Types as Comments proposal
TypeScript Congress 2023
27 min
What is "TC39: Type Annotations" aka the Types as Comments proposal
The TC59 Type Annotations proposal, also known as Types with Comments, introduces the ability to run typed code in JavaScript. It aims to bring TypeScript back into JavaScript and create a separation between type system and runtime. TypeScript's popularity is on par with JavaScript, raising concerns about the influence of Microsoft. The proposal progresses by addressing runtime interaction and token soup in type specifications. Research, community involvement, and quantifying the effects of supporting this comment style are important goals.
Zod === Typescript, but at Runtime in Your React ApplicationsWatch video: Zod === Typescript, but at Runtime in Your React Applications
React Summit 2023
8 min
Zod === Typescript, but at Runtime in Your React Applications
Today's Talk discusses how Zod, an NPM library, can guarantee the TypeSystem at runtime, providing all the benefits of TypeScript. Zod's parse method allows for checking if objects match the schema, creating a validation layer between applications and APIs. By combining TypeScript with Zod, developers can ensure type safety at both runtime and build time, preventing code execution with incorrect data and improving the user experience.
Pushing the Limits of Video Encoding in Browsers With WebCodecs
JSNation 2023
25 min
Pushing the Limits of Video Encoding in Browsers With WebCodecs
Top ContentThis Talk explores the challenges and solutions in video encoding with web codecs. It discusses drawing and recording video on the web, capturing and encoding video frames, and introduces the WebCodecs API. The Talk also covers configuring the video encoder, understanding codecs and containers, and the video encoding process with muxing using ffmpeg. The speaker shares their experience in building a video editing tool on the browser and showcases Slantit, a tool for making product videos.
How I Like to Write JavaScript
JSNation 2023
26 min
How I Like to Write JavaScript
Caleb Porzio introduces Alpine JS, a JavaScript framework, and demonstrates the process of creating a scrappy version of AlpineJS and refactoring it. The Talk covers topics such as creating a Dom Walker, evaluating expressions, using mutation observers, and refactoring the code. It also discusses techniques like inverting conditionals, using callbacks, and parameter currying. The Talk emphasizes the importance of abstraction, handler extraction, and a declarative approach in software development.
JavaScript Iteration Protocols
JSNation 2023
27 min
JavaScript Iteration Protocols
We are working on troubleshooting a production issue in a startup. The CTO identified a problem with loading large files into memory and suggested reading the file line by line. We learn about iterators and generators in JavaScript, which allow us to process data one item at a time. Generators can be used to combine async and generator functions for file processing. The speaker also discusses using a for loop instead of map, filter, and reduce. The Talk concludes with the speaker mentioning poly-filling the implementation using core.js and offering free workshops on iteration protocols and Node.js streams.
Let’s Get Visual - Visual Testing in Your Vue.JS Project
Vue.js London 2023
22 min
Let’s Get Visual - Visual Testing in Your Vue.JS Project
This Talk discusses the importance of fixing small UI errors and typos, as they can leave a negative impression and raise questions about trust in applications. Traditional testing methods may not catch all UI errors, so visual testing is introduced as a solution. The Visual Regression Tracker is recommended as a tool for managing visual test results. Best practices for visual testing include ensuring the application is fully loaded, addressing flakiness, and handling false negatives. The key lessons include giving tests eyes, looking beyond the given path, using visual testing, and covering the original with suitable tests if consistent results can't be obtained.
Securing Your Software Supply Chain
Node Congress 2023
21 min
Securing Your Software Supply Chain
Today's Talk focuses on securing the software supply chain, particularly in the JavaScript ecosystem. The number of transitive dependencies in JavaScript projects can contribute to vulnerabilities. Attacks on the open-source supply chain have increased significantly, leading to initiatives to improve supply chain security. Accuracy in package manager dependencies is crucial, and caching and bundling dependencies can help achieve reproducible installations. Mitigating threats involves active scanning, creating profiles, and sharing information. Tools like NPM Audit Signatures can verify package integrity. Future developments include reproducible installations and powerful dependency queries.
Parse, Don’t Validate
Node Congress 2023
26 min
Parse, Don’t Validate
2 authors
Hello. We're going to talk today about JavaScript and how to ensure data correctness. JSON can be wasteful and has security issues, but Fastify tackles these challenges. JTD is better than JSON Schema for most API use cases, as it has a more strict structure and avoids debugging issues. Jason demonstrates how to validate data with JTD and TypeScript, ensuring data validity and improving performance. The approach of parsing JSON directly to the application type and serializing a specific type improves security and reliability.
Roll you own JavaScript runtime
Node Congress 2023
21 min
Roll you own JavaScript runtime
This Talk introduces Deno, a custom JavaScript runtime similar to Node.js, and discusses the benefits of using a custom runtime. It explores the process of building a custom runtime with Deno in Rust, including the integration with Cargo and the ability to mix and match crates and APIs. The Talk also covers the implementation of the setTimeout function in both Run.js and Runtime.js, and provides examples of how to fix errors and implement additional functions. Overall, the Talk highlights the flexibility and possibilities of creating custom runtimes with Deno.
Things I learned while writing high-performance JavaScript applications
Node Congress 2023
31 min
Things I learned while writing high-performance JavaScript applications
Top ContentThis talk explores the creation of a full-text search engine in JavaScript, highlighting the challenges with existing search engines like Algolia and the advantages of using JavaScript. The speaker emphasizes the importance of code optimization and performance enhancement techniques in JavaScript. The talk also discusses the evolution of the Lyra search engine into the open-source project Orama, which offers a feature-rich and highly performant full-text search engine for JavaScript. The speaker addresses questions about language choice, scalability, and deployment, and showcases the benefits of deploying an immutable database to a CDN.
Eval all the strings! - Hardened JavaScript
Node Congress 2023
8 min
Eval all the strings! - Hardened JavaScript
NPM packages can be potentially dangerous, so it's important to be proactive in managing them. Lava Mode allows you to detect and investigate suspicious packages before deploying your app. Lavamote prevents unauthorized access to sensitive resources by isolating dependencies and using hardened JavaScript. Lava Mode makes it easier to analyze obfuscated files and understand their actions.
JS Character Encodings
Node Congress 2023
33 min
JS Character Encodings
Character encodings are important for converting characters into bytes. UTF-8 is the most commonly used encoding in JavaScript. JavaScript engines handle character encodings automatically. There are bugs in Node.js related to character encoding and string manipulation. It is important to be cautious when working with character encodings and to choose the appropriate method for string manipulation.
Prototype Pollution in JavaScript
Node Congress 2023
27 min
Prototype Pollution in JavaScript
This Talk discusses prototype production in JavaScript and focuses on the concept of prototype pollution. It explains the impact of prototype pollution and ways to avoid it. The Talk also highlights real-world examples of prototype pollution vulnerabilities in Kibana and MongoDB. It provides recommendations for preventing and mitigating prototype pollution, such as filtering out merge functions and using defensive objects. The Talk concludes with a discussion on tools like Semgrep for static analysis and the importance of sanitization and validation in preventing outside attacks.
Remix Persistence With DynamoDB
Remix Conf Europe 2022
41 min
Remix Persistence With DynamoDB
DynamoDB is a next-generation key-value database that is low-latency, scalable, and easy to use. It offers advantages such as local development options, a generous free tier, and fast performance. Common misconceptions about DynamoDB being expensive or hard to learn are debunked. The Talk covers topics like basic modeling, separating concerns, working with DynamoDB in Remix, and building a DynamoDB client. Overall, DynamoDB is a powerful database that integrates well with Remix and provides efficient data access patterns.
React Remixed
Remix Conf Europe 2022
19 min
React Remixed
Remix is a full stack web framework that focuses on the user interface and works back to web standards. It eliminates render and fetch waterfalls in web applications, resulting in improved performance. Remix leverages the foundations of the web and combines them with features like HTTP caching and dynamic server rendering. It allows for progressive enhancement and speeds up the user experience. Remix is a powerful tool for web development with great potential for the future.
Remixing How We Give
Remix Conf Europe 2022
32 min
Remixing How We Give
Daphne uses Remix for their web application, benefiting from its resilience, error boundaries, cache boundaries, and progressive enhancement. Remix simplifies form submission, authorization, and validation, and allows for easier refactoring and code duplication avoidance. Next and Remix are used together, with Remix serving as the backend for the frontend and handling data aggregation. Remix provides query functions for fetching data, mutations for form data validation and API calls, and custom conventions using the handle export. Migrating to Remix resulted in smaller JavaScript files, faster navigation, and the ability to preload data and assets. The migration process took around nine months and involved mixing Next.js and Remix using Express. Hiring someone to work on Remix is easier than hiring for other frameworks.
The New Frontier: E-Commerce at the Edge
Remix Conf Europe 2022
19 min
The New Frontier: E-Commerce at the Edge
Today's Talk discusses the new frontier of e-commerce at the edge, focusing on headless commerce and the benefits it offers. The edge, an intermediate server, can improve website loading by rendering HTML on the server and reducing latency. Venger, an open-source headless e-commerce framework, is introduced as a solution to cache API responses at the edge and improve performance. The Venger online shop demonstrates excellent performance, highlighting the benefits of headless and edge computing in e-commerce.
Remixing a Symfony
Remix Conf Europe 2022
19 min
Remixing a Symfony
This Talk discusses Harvey's performance journey and how it led to the adoption of Remix. The engineering team addressed scaling and performance issues through backend fixes and frontend improvements. The redesign focused on loading products by category and prioritizing performance. The implementation of Remix resulted in improved performance and a reduction in API requests. The focus on long-term scalability is essential for handling a growing product list and customer base.
Demystifying Web Accessibility
Remix Conf Europe 2022
11 min
Demystifying Web Accessibility
Web accessibility ensures that people with disabilities can use and participate equally on the web. Over 15% of the global population has some form of disability. Improving web accessibility can be done using tools like ex-DEV tools and the web disability simulator. Color contrast plays a crucial role in readability, and semantic HTML and tab order help with functionality and user flow. There are additional tools and extensions available for further exploration.
Let’s Remix to Localize Content!
Remix Conf Europe 2022
36 min
Let’s Remix to Localize Content!
This Talk introduces Remix and internationalization, highlighting the impact and importance of internationalization in software development. It explores different approaches to internationalizing URLs and the use of Remixi18next for internationalization in Remix. The Talk covers the creation and configuration of translated files, as well as the importance of loading translation files before hydration for improved performance. It discusses the challenges and benefits of localization, including the use of folder-level translation and dynamic routes. The Talk also touches on different translation approaches and the importance of considering user experience and understanding in different languages.
How Remix and Prisma Make Frontend Devs Fullstack
Remix Conf Europe 2022
22 min
How Remix and Prisma Make Frontend Devs Fullstack
Remix and Prisma enable front-end developers to become full-stack developers by working across different parts of the stack without diving into complexities. They provide a great framework for writing code and interacting with databases, making it easier to be a full-stack developer. Prisma's ORM allows mapping database models to JavaScript or JSON models. Developing a full stack app with Remix requires structuring components and loaders differently, but simplifies development by focusing on one place.
Remix Architecture Patterns
Remix Conf Europe 2022
23 min
Remix Architecture Patterns
Top ContentThis Talk introduces the Remix architecture patterns for web applications, with over 50% of participants using Remix professionally. The migration from single page applications to Remix involves step-by-step refactoring and offers flexibility in deployment options. Scalability can be achieved by distributing the database layer and implementing application caching. The backend for frontend pattern simplifies data fetching, and Remix provides real-time capabilities for collaborative features through WebSocket servers and Server-SendEvents.
E2E Tests for Web3 Applications
TestJS Summit 2022
21 min
E2E Tests for Web3 Applications
Top ContentIn this Talk, Rafaela discusses Web3, its decentralized and token-based model, and the architecture based on smart contracts. Testing Web3 poses challenges due to the need for third-party providers like MetaMask. Approaches such as mocking the Web3 flow and using end-to-end testing tools like Taskafar are suggested. The trade-offs in Web3 testing include test speed and dependency on third-party apps. Balancing unit, integration, and end-to-end tasks is crucial for a robust testing strategy.
Playwright Can Do This?
TestJS Summit 2022
23 min
Playwright Can Do This?
Playwright is a powerful tool for end-to-end testing, offering support for all major browsers and platforms. It provides features like parallelization, built-in waiting, and assertions. Playwright allows for running tests on multiple browsers with a single command and has functionality for generating tests and performing visual regression testing. It also enables the manipulation of the network layer and loading internals of web pages. Best practices include using short and idempotent scripts, splitting user account flows into separate tests, and cleaning up after each test case.
Using Tests for What?!
TestJS Summit 2022
11 min
Using Tests for What?!
Today's Talk introduces VEST, a form validation framework that combines the syntax and style of Unitest with form validation. The lack of structure in form validation is a major problem, leading to messy and difficult-to-maintain code. Testing forms and form validation can be challenging, especially with complex logic. VEST offers a solution by allowing the creation of a form validation suite using unit tests. It provides features like multiple validations per field, async validations, and memoization, with support for any JavaScript environment and full TypeScript support.
Zero Dependency Testing With Node.js
TestJS Summit 2022
10 min
Zero Dependency Testing With Node.js
Today's Talk is about zero dependency testing with Node.js. The new test runner in Node.js supports CLI and standalone file execution, and different test runner styles are supported. Writing tests with Node.js is simple using its assert and test modules. The test runner passed one test and failed another, and future work includes implementing a tap parser and adding code coverage and mocking features.
Automated Security Testing for JS Apps
TestJS Summit 2022
9 min
Automated Security Testing for JS Apps
At StackHawk, we do application security testing, specifically dynamic application security testing. Legacy DAST tools are not effective for testing JavaScript front ends and APIs. To achieve better testing, it is essential to drive the API directly using industry standards like postman collections, OpenAPI spec, GraphQL, and introspection queries. StackHawk simplifies finding and fixing security issues in applications, integrating with CI/CD processes and providing simple descriptions and examples. Start a free trial at stackhawk.com to improve software quality.
Overtesting: why it happens and how to avoid it
TestJS Summit 2022
7 min
Overtesting: why it happens and how to avoid it
This talk is about overtesting, a technique to improve test suites and testing proficiency. It addresses the common problem of spending excessive time on maintaining test suites. The goal is to maintain 100% coverage while spending equal or less time on test suites. The talk suggests splitting tests into functional units, using expect object containing for manageable expectations, and prioritizing ease of testing and time spent.
Challenges of Testing and Monitoring WebRTC Applications
TestJS Summit 2022
21 min
Challenges of Testing and Monitoring WebRTC Applications
WebRTC is an HTML5 specification for real-time media communications between browsers and devices, with challenges in testing and monitoring. Browsers frequently update, potentially breaking WebRTC applications. Testing requires browser automation, consideration of network conditions, and device characteristics. Virtual machines and raw data injection are important for testing. Manual testing is necessary for specific workflows and scalability. Orchestrating multiple machines in the cloud and validating video, packet loss, and bit rate are challenges. Visibility and analysis of WebRTC API calls and metrics are crucial. TestRTC by Spearline offers testing and monitoring solutions.
Delightful Integration Tests With Testcontainers
TestJS Summit 2022
21 min
Delightful Integration Tests With Testcontainers
Top ContentTesting is crucial for development and production, with integration tests becoming more popular. Test containers is a library that integrates with Docker to create reliable test environments. It is flexible and can be used with various frameworks and test libraries. The IDE setup involves configuring the container and connecting it to the application. Test containers can be used for complex operations and allows running tests with real dependencies.
Unit Testing Angular Applications
TestJS Summit 2022
24 min
Unit Testing Angular Applications
This talk explores unit testing in Angular applications, covering topics such as testing front-end applications, specifics of testing Angular, best practices, and educational resources. It discusses the anatomy of a unit test in both Jasmine and Jest, the setup and initial tests in Angular, testing user interaction and event handlers, testing rendered output and change detection, and unit testing parent components with child components. It also highlights best practices like using test doubles, testing components with dependency injection, and considerations for unit testing. Code coverage is emphasized as a metric that doesn't guarantee bug-free code.
Beyond Rest - Contract Testing in the Age of gRPC, Kafka and GraphQL
TestJS Summit 2022
22 min
Beyond Rest - Contract Testing in the Age of gRPC, Kafka and GraphQL
This talk explores the challenges of API communication in a multi-protocol environment and the limitations of REST. It discusses how contract testing can address these challenges by focusing on API communications and reducing reliance on end-to-end tests. The talk also examines the limitations of specifications like OpenAPI and JSON schema and the challenges of endpoint evolution and versioning. It highlights the benefits of consumer-driven contract testing in ensuring API compatibility and provides an overview of the PACT framework as a standardized solution.
Testing Mail Service With Playwright
TestJS Summit 2022
17 min
Testing Mail Service With Playwright
Top ContentThis Talk discusses how to test mail service with Playwright, covering e-mail verification, reset password user journey, and more. It explores the use of third-party providers for reliable e-mail delivery and demonstrates how Playwright can help perform checks on e-mail content. The Talk also introduces the concept of a fake SMTP server and showcases how fixtures can be used to access the SMTP server and perform assertions on the HTML body of emails. Playwright's HTML rendering feature allows for interaction with email content as if it were a regular web page. It highlights the ability to render HTML from API calls, perform assertions on the rendered page, and exclude dynamically generated data from visual regression tests.
Machine Learning based Unit Tesing in JavaScript
TestJS Summit 2022
22 min
Machine Learning based Unit Tesing in JavaScript
This talk explores machine learning-based unit testing in JavaScript and TypeScript, focusing on tools like the Pony Code VS Code extension and GitHub Copilot. The Pony Code tool provides a graphical user interface for generating and managing unit test cases. GitHub Copilot acts as an intelligent code auto-completion tool, understanding the context of the code and suggesting unit test cases. These tools aim to improve code coverage and achieve 100% coverage.
Dissecting Complexity in Tests
TestJS Summit 2022
15 min
Dissecting Complexity in Tests
Today's Talk discusses complexity in tests and how to effectively deal with it. The speaker emphasizes the importance of testing critical user-facing paths and modeling tests from the user's perspective. They also highlight the significance of creating a testing setup that allows any test to run smoothly and the implicit testability of a well-designed system. The Talk explores the impact of choosing the right testing environment, the role of testing setup in mitigating complexity, and the importance of test structure and expectations. The speaker provides practical tips for tackling complexity in tests, such as keeping tests flat, using helper utilities, and splitting tests into separate files.
How to Choose an Automation Tool
TestJS Summit 2022
21 min
How to Choose an Automation Tool
I am Lia, a software engineer at Nocare, and I'm going to show you a process to choose an automation tool. I'll compare three frameworks and discuss other integration options. Selenium is a well-established framework with a large community, but it requires third-party integrations for certain types of tests. Cypress is an all-in-one tool that supports unit testing, but it only works with JavaScript and lacks parallel testing capabilities. Playwright is a newer framework that is more complete and supports parallel testing, but it has a smaller community and less mature documentation. If you want a framework that does it all, choose Playwright. Documentation is essential to remember your initial thoughts, show others what is being tested, and establish good practice. Once you have your test list, chosen framework, and prioritizations, schedule a meeting with management. Present your work confidently, as it is the best approach for the team and product.
🚀 Supercharge your NodeJS with Rust
JSNation 2022
21 min
🚀 Supercharge your NodeJS with Rust
In this Talk, Dmitry Kudravtsev discusses how to supercharge JavaScript and Node.js using Rust. He introduces NEON, an open-source library for integrating Rust and JavaScript, and explains how to use it to export Rust functions to JavaScript. Dmitry also explores the performance benefits of using native modules written in Rust and WebAssembly. He compares the two approaches and highlights the faster performance of Rust native modules. He concludes by recommending WebAssembly for its ergonomics and portability, while suggesting native modules for extending Node.js with performance code.
Build Blockchain dApps using JavaScript
JSNation 2022
21 min
Build Blockchain dApps using JavaScript
Hello, my name is Russ Fustino, and welcome to Build Blockchain DApps Using JavaScript. We'll cover Algorand blockchain, layer one, setup your development environment, creating a simple DApp, verification, and UI controls from pipeline. Blockchain tools are now accessible to anyone for creating liquidity pooling, staking, and more. The Italian Society of Authors and Publishers is using NFTs on the Algorand blockchain to identify copyrights. Algorand accounts, ASAs, Atomic Transactions, Algorand Smart Contracts, and reporting with Indexer are part of the solution. Creating NFTs can be done using visual tools like Algodesk.io and wallets like Algosigner and MyAlgoWallet. Algorand atomic transfers guarantee the exchange of goods and facilitate decentralized applications. Smart signatures approve spending transactions and smart contracts facilitate global and local storage. DApp architecture includes a UI front end, payment transactions between accounts, asset transactions for NFTs and Fungible Tokens, and application calls for smart contracts. Various SDKs and tools are available, such as AlgoDesk.io, Algorand Studio, and Algodia. Reach is a high-level language and compiler for deploying DApps to the blockchain. Verification and audits play a crucial role in preventing locked away tokens. The Pipeline UI offers controls and components for easy integration into solutions.
Quantum Computing in JavaScript with Q.js
JSNation 2022
26 min
Quantum Computing in JavaScript with Q.js
Stuart Smith discusses his journey in virtual reality and quantum computing, highlighting his work in web VR and the creation of Quantum JavaScript. He introduces QGS, a platform for quantum tutorials and experimentation, and explains the concept of qubits and superposition. Smith also mentions Amazon Bracket, a quantum service that allows the building and running of quantum circuits on simulators or actual quantum hardware.
Future Features of JS?!
JSNation 2022
28 min
Future Features of JS?!
Top ContentWelcome to the future features of JavaScript, including proposals for array operations, throw expressions, records and TPUs, pipeline operators, and more. The talk covers the introduction of type assertions for imported files, non-mutating array operations, and the simplification of error handling. It also explores the concept of immutability with records and TPUs, and the use of the pipeline operator to simplify code. Other proposals include Map.implace, IteratorHelper, slice notation, type annotations, Array UNIQBY, number ranges, and the Function 1 proposal.
How JS Modules work: a Browser Perspective
JSNation 2022
26 min
How JS Modules work: a Browser Perspective
This Talk discusses JavaScript modules from the perspective of a browser, exploring how they work and their differences from common JS. It covers topics such as loading modules, module records, and the module map. The module loading and evaluation process is explained, along with the challenges of module adoption and performance. The Talk also touches on lazy loading, dynamic import, and import reflection. The speaker shares a humorous anecdote during the Q&A session about stealing a shirt from the DOM team.
Record & Tuple: Immutable Data Structures in JS
JSNation 2022
24 min
Record & Tuple: Immutable Data Structures in JS
Top ContentToday's Talk introduces the concept of record and tuple in JavaScript, which provide a new way to handle data. The Talk explores the references and mutability of objects, strings, and numbers in JavaScript. It discusses the limitations of freezing objects and proposes record and tuple as a solution. The Talk also covers methods and syntax for tuples, the status of the proposal, and acknowledges the contributions of various individuals. Overall, the Talk aims to redefine how data is handled in JavaScript and encourages waiting for broader browser support before implementing these features.
Yarn 4 - Modern Package Management
JSNation 2022
28 min
Yarn 4 - Modern Package Management
Top ContentYarn is a package manager that focuses on stability, performance, and security. It offers unique features like plug and play installation, support for nonmodules, and the exec protocol. Yarn is committed to being a good citizen in the open-source community and contributes to fixing dependencies. It is part of the Node.js Loader's working group and advocates for Corepack. Yarn is still experimental but is improving its user experience and security features. Contributions are welcome, and switching to Yarn can improve performance in large projects.
Alternatives to TypeScript
TypeScript Congress 2022
8 min
Alternatives to TypeScript
This Talk explores alternatives to TypeScript such as Clojure, Flow, and Hagel, highlighting their unique features and syntax. Flow and Hagel make finer distinctions between types and prioritize safety. TypeScript offers quick fixes for inferring types. Hagel aims for fewer type annotations and increased safety. These alternatives can provide insights and understanding of TypeScript.
A Comparison of Web Workers
Node Congress 2022
25 min
A Comparison of Web Workers
This Talk compares web workers, including dedicated workers, shared workers, and service workers. Web workers provide multithreading capabilities and use shared memory for higher performance. Dedicated workers have one parent and can execute on a separate thread. Shared workers can have multiple parents and are useful for communication across different windows. Service workers can intercept and proxy requests made from a web page and are useful for caching network assets and building progressive web apps.
Understanding JavaScript Compilation
Node Congress 2022
8 min
Understanding JavaScript Compilation
Today's Talk explores the concepts of compilation and transpilation in JavaScript, highlighting the three steps involved: parsing, code transformation, and code generation. The process of traversing an abstract syntax tree is discussed, with examples of tools like Babel and ESLint that can be used for code transformations. Code transformation tools and techniques, such as CodeShift and T-TypeScript plugin, are introduced, emphasizing the power of abstract syntax trees and the visitor pattern. The summary concludes by encouraging further exploration of code refactoring and transformations using tools like Babel, TSLint, and astexplorer.net.
The Future of JavaScript Runtimes
Node Congress 2022
34 min
The Future of JavaScript Runtimes
Today's Talk explores the future of JavaScript runtimes, their evolution, and impact on software development. It discusses the historical trends of JavaScript, the adoption of new tools and libraries, and the convergence of Node and Deno. The emergence of isolate clouds and their potential to replace traditional VMs and containers is also highlighted. Additionally, the talk touches on the possibilities of JavaScript in exotic use cases, its impact on machine learning, and the potential for TypeScript to become the de facto language for JavaScript development.
Technical SEO & JavaScript
Vue.js London Live 2021
8 min
Technical SEO & JavaScript
Technical SEO is important for making content visible to search engines. Developers have a significant impact on the crawling and indexing process. Hash-based routing can lead to duplicate content issues, and it is recommended to use the History API instead. In 2019, 12% of websites still used fragmented URLs.
What's New in npm?
DevOps.js Conf 2021
26 min
What's New in npm?
Welcome to my talk on what's new in the NPM CLI. NPMv7 introduced many new capabilities, including installing peer dependencies by default. npm v7 also introduced support for workspaces, allowing the definition of projects within your root project. The NPM team is continuously improving the CLI with weekly releases and is working on exciting features in collaboration with GitHub. NPM is not an acronym for Node Package Manager, and the CLI will continue to improve with the support of the growing team.
ESNext: Proposals To Look Forward To
JSNation Live 2020
9 min
ESNext: Proposals To Look Forward To
ES Next proposal stages include straw person, proposal, draft, candidate, and finished. Optional chaining and null coalescing operators are solutions for handling undefined and null values. Logical assignment and null coalescing operators are seeking advancement to stage four. Decimal type is introduced to address floating point math issues. Cancellation API and abort control are solutions for canceling promise execution. Pattern matching allows matching the shape of a vector and performing actions based on it.
How Does the TypeScript Team Try to Avoid Negative Effects on the JS Ecosystem
JSNation Live 2020
33 min
How Does the TypeScript Team Try to Avoid Negative Effects on the JS Ecosystem
TypeScript's influence in the JavaScript ecosystem and its alignment with JavaScript's goals and principles. TypeScript's impact on the industry and its popularity among JavaScript programmers. The goal of TypeScript to innovate in types without introducing new concepts to JavaScript. The challenges of running TypeScript on other people's code and making it a native browser language. TypeScript's compatibility with JavaScript and its aim to be a thin layer on top of JavaScript. The efforts to improve support for JS and JS docs and the pain points of transitioning to TypeScript. The accessibility work in TypeScript and the absence of real competitors in the market.
Module Federation in Webpack 5
JSNation Live 2020
32 min
Module Federation in Webpack 5
This Talk discusses module federation in Webpack 5 as a scalable solution for shared dependencies in large applications. Module federation allows separate builds for different parts of an application, reducing build time and deploy delay. It features exposed and shared modules, asynchronous loading, and container creation. Module federation supports container orchestration techniques and aims to integrate with ECMAScript modules. However, optimization and sharing in module federation may impact code size, and careful evaluation is necessary. Updating containers can be managed through active testing for stability.
CSS Can Do That Too
JSNation Live 2021
22 min
CSS Can Do That Too
This Talk is about CSS techniques that can simplify web development and eliminate the need for JavaScript. It covers topics such as responsive typography, flexible font sizing, CSS math functions, scroll snapping, sticky elements, and CSS masonry layout. The speaker emphasizes the importance of understanding how sticky elements work and highlights the potential bugs that can occur. CSS Masonry layout is discussed as a native solution for creating masonry grids in the browser. Overall, CSS provides flexible solutions for web styling and is an exciting tool for developers.
How to Outsmart Time: Building Futuristic JavaScript Apps Using Temporal
JSNation Live 2021
25 min
How to Outsmart Time: Building Futuristic JavaScript Apps Using Temporal
Temporal is a proposal in JavaScript that brings an ergonomic API for building futuristic JavaScript applications. It is now at stage 3 and implementers will start implementing it in different polyfills and browsers. Temporal includes classes for working with dates, times, time zones, calendars, and durations. The talk covers building an invoice calculator using Temporal, calculating durations between date times, creating and manipulating durations, understanding time relativity and rounding, and rewriting methods using Temporal. The speaker expresses gratitude to various contributors and provides a sandbox for exploration.
ES?.next()
JSNation Live 2021
31 min
ES?.next()
The Talk discusses various proposals for the next version of ECMAScript (ES Next) and the TC39 process. It covers features such as binding syntax, shorthand property assignments, pattern matching, async match, operator overloading, and more. These proposals aim to simplify code, make it more readable, and introduce new functionalities. The Talk also addresses questions about the committee's decision-making process and the experience of being part of the TC39 committee.
Using the Proxy API for State Management
JSNation Live 2021
27 min
Using the Proxy API for State Management
This Talk introduces the concept of using proxies in JavaScript for state management. It explores the implementation of proxies, observing properties and creating caches, building the proxy, and observing changes with proxies. The Talk also discusses using the Taits library for state management and the performance implications of proxies. TypeScript and JavaScript are compared, and the results of a poll on their usage are shared.
The Third Age of JavaScript
JSNation Live 2021
30 min
The Third Age of JavaScript
Top ContentThis talk presents the Third Age of JavaScript, covering the evolution and future of the language. It explores the adoption of ES modules and the decline of IE11, as well as the changing landscape of JavaScript tooling and the concept of polyglot tooling. The talk also touches on the potential future of JavaScript with WebAssembly and emphasizes the importance of code composability and receiving feedback in software development.