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gfredericks / frobnicate.clj
Last active Mar 1, 2019
Self-contained clojure file with deps
View frobnicate.clj
#!/usr/bin/env bash
#! top-of-file comments can be written using more #! lines, which
#! is a valid comment in both clojure and bash
":";# alternately this works too
#! The construction below uses cross-language syntactic hackery to
#! specify the -Sdeps arg in a part of the file that's interpreted
#! by clojure as clojure syntax (i.e., not a line comment), so it
View deps.edn
{org.clojure/clojure {:mvn/version "1.9.0"}
com.datomic/datomic-free {:mvn/version "0.9.5697"}}}
bhb /
Last active Oct 25, 2018
Building a blockchain, assisted by Clojure spec

Building a blockchain, assisted by Clojure spec

In an effort to gain at least a superficial understanding of the technical implementation of cryptocurrencies, I recently worked my way through "Learn Blockchains by Building One" using Clojure.

This was a good chance to experiment with using spec in new ways. At work, we primarily use spec to validate our global re-frame state and to validate data at system boundaries. For this project, I experimented with using instrumentation much more pervasively than I had done elsewhere.

This is not a guide to spec (there are already many excellent resources for this). Rather, it's an experience report exploring what went well, what is still missing, and quite a few unanswered questions for future research. If you have solutions for any of the problems I've presented, please let me know!

You don't need to know or care about blockchains to understand the code be


Upload component


Based heavily on [s3-beam][1], but uses re-frame events/subs to get the job done. The /sign handler is the [s3-beam][1] handler (near verbatim).

For background on (ui.core/component "...") see

ui.ajax is just thin wrappers and/or aliases around plumbing from ajax.core from cljs-http

yogthos / gallery.cljs
Last active Aug 9, 2021
script to download walpapers from
View gallery.cljs
vbedegi / react-sortable-hoc-in-reagent.cljs
Last active Nov 29, 2017
using react-sortable-hoc in reagent
View react-sortable-hoc-in-reagent.cljs
(def react-sortable-hoc (aget js/window "deps" "react-sortable-hoc"))
(defn make-sortable-element-component [wrapped-component]
(let [sortable-element-factory (.-SortableElement react-sortable-hoc)]
(-> wrapped-component
(defn make-sortable-container-component [wrapped-component]
reborg /
Last active Dec 15, 2021
A curated collection of answers that Rich gave throughout the history of Clojure

Rich Already Answered That!

A list of commonly asked questions, design decisions, reasons why Clojure is the way it is as they were answered directly by Rich (even when from many years ago, those answers are pretty much valid today!). Feel free to point friends and colleagues here next time they ask (again). Answers are pasted verbatim (I've made small adjustments for readibility, but never changed a sentence) from mailing lists, articles, chats.

How to use:

  • The link in the table of content jumps at the copy of the answer on this page.
  • The link on the answer itself points back at the original post.

Table of Content

swannodette /
Last active Nov 28, 2019
Externs Inference

Externs Inference

Integrating third party JavaScript libraries not written with Google Closure Compiler in mind continues to both be a source of error for users when going to production, and significant vigilance and effort for the the broader community (CLJSJS libraries must provide up-to-date and accurate externs).

In truth writing externs is far simpler than most users imagine. You only need externs for the parts of the library you actually intend to use from ClojureScript. However this isn't so easy to determine from Closure's own documentation. Still in the process of writing your code it's easy to miss a case. In production you will see the much dreaded error that some mangled name does not exist. Fortunately it's possible to enable some compiler flags :pretty-print true :pseudo-names true to generate an advanced build with human readable names. However debugging missing externs means compiling your production build for each missed case. So much time wasted for such simple mistakes damages our sen

attentive / leaflet.cljs
Last active Sep 16, 2017
Adapting React components in Rum
View leaflet.cljs
(ns project.leaflet
(:require-macros [project.macros :as m])
(:require [rum.core :as rum]
cljsjs.react-leaflet)) ;; js/ReactLeaflet
(m/adapt-react leaflet-map js/ReactLeaflet.Map)
(m/adapt-react tile-layer js/ReactLeaflet.TileLayer)
(m/adapt-react marker js/ReactLeaflet.Marker)
(m/adapt-react popup js/ReactLeaflet.Popup)
robert-stuttaford / translate.clj
Last active Mar 24, 2019
Language translations for Datomic entities with fallback to base entity
View translate.clj
(ns cognician.db.translate
(:require [datomic.api :as d])
(:import [clojure.lang MapEntry]
[datomic.query EntityMap]))
;;; Language
(def default-language :en-GB)