Update build instructions in README.md

README.md

@@ -8,23 +8,31 @@ processing, text-mining, complex networks analysis and interactive data
 visualization to pave the way toward new kinds of interactions with your
 digital corpora.
 
-This software is a free software, developed by the CNRS Complex Systems
+You will not find this software very useful without also running or being
+granted access to a [backend](https://gitlab.iscpif.fr/gargantext/haskell-gargantext).
+
+This software is free software, developed by the CNRS Complex Systems
 Institute of Paris Île-de-France (ISC-PIF) and its partners.
 
-## Installation of this library
+## Development
+
+### Installing dependencies
 
-### Dependencies warning
-This library purescript-gargantext is the Front End part of Gargantext.
-you need the backend (haskell-gargantext) installation too.
+Before building gargantext, you must install the dependencies. We use
+[yarn](https://yarnpkg.com/en/) for this. They have excellent[install
+instructions](https://yarnpkg.com/en/docs/install).
 
-### Installation steps
+Then you must install the javascript and purescript dependencies:
 
-1. Add `node_modules/.bin` to your path
-2. Execute `./build`
+```shell
+yarn install && yarn install-ps
+```
 
-In one command:
+### Building
 
-```PATH="$PWD/node_modules/.bin:$PATH" ./build```
+```shell
+yarn build
+```
 
 ## Note to the contributors
 
@@ -33,7 +41,7 @@ Please follow CONTRIBUTING.md
 ## Introduction
 
 Making sense of out text isn't actually that hard, but it does require
-a little background knowledge to understand.x
+a little background knowledge to understand.
 
 ### N-grams
 
@@ -61,6 +69,8 @@ N-grams are matched case insensitively and across whole words. Examples:
 
 You may read more about n-grams [on wikipedia](https://en.wikipedia.org/wiki/N-gram).
 
+<!-- TODO: Discuss punctuation -->
+
 Gargantext allows you to define n-grams interactively in your browser
 and explore the relationships they uncover across a corpus of text.