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Tim Kendall timkendall

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  • Orange, CA
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Domain Modeling with Tagged Unions in GraphQL, ReasonML, and TypeScript

GraphQL has exploded in popularity since its open-source announcement in 2015. For developers who had spent a lot of time managing data transformations from their back-end infrastructure to match front-end product needs, GraphQL felt like a tremendous step forwards. Gone were the days of hand-writing BFFs to manage problems of over-fetching.

A lot of value proposition arguments around GraphQL have been about over/under fetching, getting the data shape you ask for, etc. But I think GraphQL provides us more than that—it gives us an opportunity to raise the level of abstraction of our domain, and by doing so allow us to write more robust applications that accurately model the problems we face in the real world (changing requirements, one-off issues).

An underappreciated feature of GraphQL is its type system, and in particular features like [union types](https:

WebReflection /
Last active March 4, 2024 20:55
NodeJS Executable Standalone Module


If you're OK in having a node-esm executable, please consider this solution.

#!/usr/bin/env sh
# the /usr/local/bin/node-esm executable
exec node --input-type=module - $@ <$input_file
Yogu / socket-keeper.ts
Last active March 19, 2020 23:51
max-age for keep-alive in node
import { injectable } from 'inversify';
import { Logger } from 'log4js';
import { Socket } from 'net';
import Timer = NodeJS.Timer;
export interface KeepaliveOptions {
* The maximum time in milliseconds an unused socket will be kept alive before it will be closed
* This should be set to a smaller value than the server's keepalive timeout to avoid a race condition
Rich-Harris /
Last active March 27, 2024 06:09
The truth about Svelte

I've been deceiving you all. I had you believe that Svelte was a UI framework — unlike React and Vue etc, because it shifts work out of the client and into the compiler, but a framework nonetheless.

But that's not exactly accurate. In my defense, I didn't realise it myself until very recently. But with Svelte 3 around the corner, it's time to come clean about what Svelte really is.

Svelte is a language.

Specifically, Svelte is an attempt to answer a question that many people have asked, and a few have answered: what would it look like if we had a language for describing reactive user interfaces?

A few projects that have answered this question:

Rich-Harris /
Last active September 24, 2023 20:08
first-class binding syntax

A modest proposal for a first-class destiny operator equivalent in Svelte components that's also valid JS.

Svelte 2 has a concept of computed properties, which are updated whenever their inputs change. They're powerful, if a little boilerplatey, but there's currently no place for them in Svelte 3.

This means that we have to use functions. Instead of this...

<!-- Svelte 2 -->
<h1>HELLO {NAME}!</h1>

Libuv and libev, two I/O libraries with similar names, recently had the privilege to use both libraries to write something. Now let's talk about my own subjective expression of common and different points.

The topic of high-performance network programming has been discussed. Asynchronous, asynchronous, or asynchronous. Whether it is epoll or kqueue, it is always indispensable to the asynchronous topic.

Libuv is asynchronous, and libev is synchronous multiplexing IO multiplexing.

Libev is a simple encapsulation of system I/O reuse. Basically, it solves the problem of different APIs between epoll and kqueuq. Ensure that programs written using livev's API can run on most *nix platforms. However, the disadvantages of libev are also obvious. Because it basically just encapsulates the Event Library, it is inconvenient to use. For example, accept(3) requires manual setnonblocking after connection. EAGAIN, EWOULDBLOCK, and EINTER need to be detected when reading from a socket. This is a

lattner /
Last active June 8, 2024 03:41
Swift Concurrency Manifesto
theorygeek / association_loader.rb
Last active October 31, 2023 07:15
Preloading Associations with graphql-batch
# frozen_string_literal: true
class AssociationLoader < GraphQL::Batch::Loader
attr_reader :klass, :association
def initialize(klass, association)
raise ArgumentError, "association to load must be a symbol (got #{association.inspect})" unless association.is_a?(Symbol)
raise ArgumentError, "cannot load associations for class #{}" unless klass < ActiveRecord::Base
raise TypeError, "association #{association} does not exist on #{}" unless klass.reflect_on_association(association)
@klass = klass
kentcdodds /
Created December 21, 2016 05:54
esnextbin sketch
jbaxleyiii / test.js
Created November 15, 2016 19:43
react-apollo testing
import { Component } from "react";
import { print } from "graphql-tag/printer";
import { graphql } from "react-apollo";
import { MockedProvider } from "react-apollo/test-utils";
import { addTypenameToDocument } from "apollo-client/queries/queryTransform";
import { mount } from "enzyme";
import { withSavedPayments, SAVED_ACCTS_QUERY } from "../";