TS Congress is an online event for web developers on all things TypesScript. Learn from industry professionals and community members, exchange ideas, interact, and collaborate in the form of a modern tech event. September 21 & 22, 2023.

TS Congress

TS Congress is an online event for web developers on all things TypeScript. Learn from industry professionals and community members, exchange ideas, interact, and collaborate in the form of a modern tech event.

TypeScript Congress 2023

FocusReactive

Grafbase

Rollbar

Rollbar is the Error Monitoring solution for developers looking to find and fix errors quickly. This offer provides a $250 dollar credit towards any paid subscription for one year. Allowing you to improve your software quality for both your frontend and backend code.

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FocusReactive will help you architect, build, and lead technically advanced websites focusing on performance and scalability. Partners and <a href="https://focusreactive.com/next-js-expert-agency/" target="_blank" rel="noopener noreferrer">experts in Next.js/Vercel</a>, Storyblok, Sanity, Contentful, Shopify Hydrogen, and other Headless eCommerce platforms.Whether you seek <a href="https://focusreactive.com/headless-cms-expert-agency/" target="_blank" rel="noopener noreferrer">expert Headless CMS agency</a> services or an expert agency with deep experience with platforms like <a href="https://focusreactive.com/storyblok-expert-agency/" target="_blank" rel="noopener noreferrer">Storyblok</a> or <a href="https://focusreactive.com/sanity-expert-agency/" target="_blank" rel="noopener noreferrer">Sanity</a>, FocusReactive is the one to help you scale.

As a special perk, we're offering a complimentary NextJS audit designed to pinpoint areas for optimization, improve performance, and ensure you're following the best practices for SEO and security.&nbsp; Our expert team will closely examine your implementation, provide actionable insights, and help you leverage the full power of NextJS.

Free NextJS Performance and SEO Best Practices Audit

Next.js, Headless CMS and eCommerce expert agency

Generating types without climbing a tree

Matteo Collina

Exploring the TypeScript-first architecture of modern frameworks

Lydia Hallie

Publishing TS Libraries for Fun and Profit

Mark Erikson

What is "TC39: Type Annotations" aka the Types as Comments proposal

Orta Therox

Making Magic: Building a TypeScript-First Framework

Daniel Roe

Taming Language Models through TypeScript

Daniel Rosenwasser

TypeScript Survival Guide: Life-Saving Tips and Techniques

Lucas Santos

Let's Make a Generic Inference Algorithm

Ryan Cavanaugh

TypeScript Performance: Going Beyond the Surface

Aleksandra Sikora

The Lies We Tell Ourselves Using TypeScript

 Stefan Baumgartner

Running TypeScript in WebAssembly on the Cloud

Matt Butcher

Infer multiple things at once with reverse mapped types 

Mateusz Burzyński

Unlocking TypeScript's Potential: Exploring the Power of Ecosystem Tooling

Lizz Parody

How to make our CLIs safer with types?

Maël Nison

Using TypeScript with Key/Value Databases

Kevin Whinnery

Unify Data Sources with GraphQL at the edge

Jamie Barton

Unleashing Object Proxies: Building Type-Safe Wrappers for Anything

Akash Joshi

Are the (module) types wrong?

Andrew Branch

Lessons Learned While Learning Live

Jenn Junod

ArkType: Bringing TypeScript to Runtime

David Blass

Migrating TypeScript to Modules: The Fine Details

Jake Bailey

Faster TypeScript builds with --isolatedDeclarations

Titian-Cornel Cernicova-Dragomir

From Theory to Practice: harnessing Typescript for successful Atomic Design implementation

Nathalia Rus

Replacing Shell Scripts with Cross-Platform TypeScript

David Sherret

How TypeScript is integrated in your editor

Maria Solano

Enhanced AST Static Analysis with Typescript Language Server

Artur Kenzhaev

Advanced linting rules with ESLint 

Tibor Blenessy

The Potential of Higher-Kinded Types for Library Semantics

Michael Poteat

Generating Typed Code

Paul Serraino

A deep dive into the proposal which could de-fork TypeScript and bring all us users back to being "JavaScripters, but with some TypeScript types." We'll cover the author's motives, how it could work, why now and how it is going.ort

Talking in front of an audience = scary. Learning something new = scary. Let’s talk about doing scary learning something new, WHILE being in front of an audience! One year and 100+ videos streamed, learning TypeScript the way I learn, has helped it click in a snowball effect helping other topics ranging from Python to APIs make more sense. In this talk, the audience will walk away with an understanding of figuring out how you learn as an individual is a lifelong gift you never knew you needed.

I'll dive into the internals of Nuxt to describe how we've built a TypeScript-first framework that is deeply integrated with the user's IDE and type checking setup to offer end-to-end full-stack type safety, hints for layouts, middleware and more, typed runtime configuration options and even typed routing. Plus, I'll highlight what I'm most excited about doing in the days to come and how TypeScript makes that possible not just for us but for any library author.

You've probably played with bots like ChatGPT and used them to brainstorm. Maybe you've noticed that getting responses in the right structure or format has been a challenge. As people, we're okay with that - but programs are much more finicky. We've been experimenting with using TypeScript itself as a way of guiding and validating responses from language models.

Learn about inferring with reverse mapped types to create great inferences for arguments that aggregate different items of the same shape. The technique can help you to introduce type-level relationships within objects and tuples. The talk will start with the introduction to the technique and will go through a couple of real-world-like examples of how this can be used to improve library types.

TypeScript goes beyond annotating syntax. We’ll explore how modern frameworks leverage type-safety at the project-level to empower better architecture, greater stability, and higher velocities.

ArkType is a new runtime validator for TypeScript and the first library with the goal of making type syntax available 1:1 in JS with no compilation step. It uses a carefully optimized static parser so that with each character you type, you'll see a list of completions, a clear ParseError, or your inferred type. At runtime, a simple definition like "string|number[]" will be transformed into a TypeNode that can be used to validate or transform inputs, compared to other TypeNodes, or combined with other definitions to form new TypeNodes. This talk will cover the process of building ArkType, with a focus on the type-level parser and runtime type system, and demo some of the most exciting features like scopes, index signatures and generics.

Key/value (KV) databases are becoming ever more popular in web applications. Their super-fast response times and ability to support eventual consistency reads make them especially well suited for apps running on globally distributed edge servers. But with how fast this tech is moving, you might not be fully up to speed on how to use this type of database with TypeScript. In this session, we'll explore good use cases for KV databases, examine several production deployment options, and demonstrate how to effectively hydrate TypeScript objects from values in a KV database.

Type-checking a TypeScript codebase can be slow, especially for monorepos containing lots of projects that each need to use the type checker to generate type declaration files. In this talk, we introduce — for the very first time — a new TypeScript feature we are working on called “Isolated Declarations” that allows DTS files to be generated without using the type checker at all! This opens the door to faster declaration generation in TypeScript itself, as well as in external tools written in other languages such as ESBuild and swc. You'll see how to use this new option, and maybe (just maybe) you’ll be convinced about the benefits of explicit return types! Most importantly, we will show how Isolated Declarations enables parallel builds to spread work across your CPU cores to significantly improve the build speed of your TypeScript projects.

In this talk, we will explore the various issues encountered when building JavaScript CLIs, and demonstrate how TypeScript can address them and help us make our applications safer. By the end of this talk, you'll understand how to abstract runtime validations type behind easy-to-use interfaces, and have all the tools you need to bring those benefits into your own CLIs at little cost - whether they are open-source projects, or internal tools.

How can an editor ""automagically"" show type errors when you create a single TypeScript file without running ""npm install typescript"" or having a tsconfig.json file? Is a completion list build by your coding editor, TypeScript itself, or some other mysterious being? What is TSServer? In this talk I will give you an overview of how the TypeScript server communicates with IDEs and other editors, delivering rich language features without ever running tsc.

How safe is TypeScript's type safety? How much can you trust your statically typed code? Can you even consider TypeScript's type system "strong"? In this talk, we look at situations where TypeScript fails badly and learn why things have to be that way. We talk about trade-offs, workarounds, and ultimately solutions for all the damn, terrible lies we tell ourselves when using TypeScript.

Everyone mentions the importance of code "scalability" and "maintainability" and how Typescript helps with it. But when I got started in tech, I remember struggling to find a practical "real-world" example with best practices. My talk aims to provide such a practical, step-by-step example, sharing some of my learnings and shortcomings: crucially, how we leveraged typescript and atomic design - without over-engineering too early.ty

For the past six at Rollbar the engineering team has been working tirelessly to migrate our legacy application to a modern Javascript tech stack. We’ve leveraged Next.js, GraphQL and a number of other JS tools to ship more features, make our dev team happier and achieve an impressive 7-fold reduction in our p99 app performance. I invite you to join me as I present the various techniques and architecture we choose to use to quickly migrate away from our legacy monolith.

How does generic inference in TypeScript work? For most people, this can seem like a black box. TypeScript's developer lead, Ryan Cavanaugh, walks us from a simple single-step generic inference algorithm up to a simplified model of how generic inference in TypeScript actually works, with a focus on motivating examples.

Do you ever find yourself pondering how to identify and address performance issues in TypeScript to maximize the effectiveness of your code? If so, join us for a talk on the performance of TypeScript and the techniques you can use to get the most out of your code. We'll delve into various ways to debug performance, explore how to leverage the power of the TypeScript compiler to detect potential performance issues and use the profiling tools available to track down the underlying bottlenecks.

How do you generate types dynamically? How do you write a script that creates some typescript code? The approach most people would recommend is to use Abstract Syntax Tree manipulations. I was working on a deadline to implement types for our OpenAPI client, and I would have missed our release window. I needed something different and easier to build. Luckily, a friend recommended me a library I didn't know: code-block-writer. I fall in love with it at first sight.

Combine multiple APIs and databases into a single centralized GraphQL API that you can enhance with auth, permissions and caching, fully managed and deployed to the edge with Wasm.

Build serverless functions in TypeScript, and then compile them to WebAssembly (Wasm) to be run in the cloud. This is a different model than the original Wasm design suggested, but it is proving to be a powerful concept. In this talk, we dive into the background of Wasm, then look at its broader applications before examining a novel way of building TypeScript code into a Wasm binary for execution in the cloud.

In TypeScript 5.0, the TypeScript toolchain migrated to modules. In this talk, we'll get deep in the weeds, discussing what "modules" even are (and how we somehow weren't using them), the specifics of the migration itself, how we managed to make the switch "mid-flight" on an actively-developed project, how the migration went, and what's next.

Most of the ecosystem tools, like bundlers or transpilers, are based on AST. And Typescript provides one of the best Developer Experiences to work with the code base. This talk is about the experience of how beneficial it can be to use Type Hints and Typescript Language Server during the AST and static code analysis, based on the example of building a compile-time css-in-js library.

Dive into the world of TypeScript ecosystem tooling and uncover the transformative capabilities that can supercharge your development workflow. In this talk, you can discover essential tools for project setup, code analysis, testing, and deployment. Also, learn how intelligent code editors, formatters, and linters improve code quality. Finally, let's explore type checkers, static analyzers, and refactoring tools that enhance codebase maintainability, TypeScript libraries and frameworks, and witness their seamless integration with bundlers, task runners, testing frameworks, and CI pipelines. Don't miss this talk to unleash the full potential of TypeScript and maximize your productivity with the extensive ecosystem of tools at your disposal and that you probably didn't know!

Publishing libraries to NPM is easy - just `tsc &amp;&amp; npm publish` and you're done, right? Whoops, you forgot proper ESM compat. And a user is asking for a UMD build. And it doesn't work in Webpack 4. And `moduleResolution: "node16"` can't find the types. Publishing libraries today is _complicated_. We'll take a look at the many problems and questions you should consider when publishing a package, and some hard-earned possible answers to those questions.type

Shell scripts serve a useful purpose, but they have some downsides. What if we could overcome these issues and make our scripts more powerful by utilizing familiar cross-platform TypeScript? In this talk, we'll discuss why you should switch your shell scripts to TypeScript and demonstrate a possible approach.

This talk will explore more advanced ways to write static analysis rules in ESLint using ESLint's control flow APIs. I will quickly explain what a control flow graph is and how you can use it to find issues in your code. I will show you how to detect when a value is assigned to variable uselessly and other logical problems you can detect using this technique.

Have you ever installed a dependency, imported it just like the README instructs, and immediately been met with strange TypeScript errors about default imports, the output module format, or ESM/CommonJS interoperability? When everything works at runtime but TypeScript complains, you might wonder, is this a TypeScript bug? Or… are the types wrong? The JavaScript module and package publishing landscape is complicated. Nearly one third of the most popular types-included npm packages have some sort of module-related typings issue that can cause confusion for users. But things are starting to improve. In this talk, we’ll: - explore how we got here—why are things complicated? - develop a simple and accurate mental model for how TypeScript sees packages - see how the `arethetypeswrong` tool can help catch issues before publishing - look at trends in the `arethetypeswrong` data for popular packages over time - discuss next steps for making the typed package ecosystem better

There is a wall that we all hit when developing more sophisticated types: how can I 'abstract out' certain commonalities in my type-level logic? How can I make my types more reusable and composable? How can I make my types more expressive? This talk will introduce the fundamentals of Higher-Kinded Types, a compelling concept hitherto underutilized, and explore how they can significantly enhance the expressiveness of library semantics, leading to a more intuitive developer experience (DX). We'll demonstrate how HKTs can provide an elevated abstraction level, allowing you to model complex domain problems more naturally and in a type-safe manner. Join us to understand how leveraging HKTs can elevate your TypeScript coding practice, optimizing the semantics and delivering a more potent and featureful library interface.

Let's go through your survival kit for the TS jungle! In this talk, you'll get the complete TS guide from simple tips to complex techniques that will help you take the most of TypeScript not only in those large production projects, but also in your small hobby idea. We'll explore validations, configuration, typings and much more.

You must or must not have heard of object proxies before, but have you ever understood how to use them? What the actual usecase of an object proxy is? In this talk, we will do a deep dive into object proxies, understanding how they work, and the kinds of things you can build using them. We will build higher-order wrappers for existing libraries, and learn how to wrap over them in a type-safe manner.

During this session you will learn how to create a new Rollbar account and integrate the Rollbar SDK with your application to monitor errors in real-time and respond and fix those errors. We will also cover how to customize payload data sent to Rollbar to extend your monitoring capabilities. Agenda:- Create a Rollbar Account (Free Account)- Integrate your application with the Rollbar SDK- Send handled and unhandled errors to Rollbar- Add Custom payload data to your configuration.

Live Coding Workshop to Setup Rollbar Error Monitoring

Nico Krüger

In this hands-on workshop, Maurice will personally guide you through a series of exercises designed to empower you with a deep understanding of React Server Components and the power of TypeScript. Discover how to optimize your applications, improve performance, and unlock new possibilities.   During the workshop, you will: - Maximize code maintainability and scalability with advanced TypeScript practices - Unleash the performance benefits of React Server Components, surpassing traditional approaches - Turbocharge your TypeScript with the power of Mapped Types - Make your TypeScript types more secure with Opaque Types - Explore the power of Template Literal Types when using Mapped Types   Maurice will virtually be by your side, offering comprehensive guidance and answering your questions as you navigate each exercise. By the end of the workshop, you'll have mastered React Server Components, armed with a newfound arsenal of TypeScript knowledge to supercharge your React applications.   Don't miss this opportunity to elevate your React expertise to new heights. Join our workshop and unlock the potential of React Server Components with TypeScript. Your apps will thank you.

Practice TypeScript Techniques Building React Server Components App 

Maurice de Beijer

Learn how to generate instant GraphQL APIs using a data source connector (GraphQL and non-GraphQL sources), extend and join them both with custom resolvers and deploy to the edge without leaving the code editor.

The Type of Conference Developers Need