anchor.diff:  BUILDKITE_PARALLEL_JOB_COUNT=5
   ```
   
  -The `BUILDKITE_PARALLEL_JOB` environment variable is the job number starting from 0, in this case each job’s value would be `0`, `1`, `2`, `3`, and `4`.
  +The `BUILDKITE_PARALLEL_JOB` environment variable stores the job number starting from 0. In this case each job’s value would be `0`, `1`, `2`, `3`, and `4` respectively.
   
  -The `BUILDKITE_PARALLEL_JOB_COUNT` environment variable is the total number of jobs.
  +The `BUILDKITE_PARALLEL_JOB_COUNT` environment variable stores the total number of jobs created from this step for this build.
   
   You can use these two environment variables to divide your application’s tests between the different jobs.
   
   ## Libraries
   
  -The following libraries have built-in support for the `BUILDKITE_PARALLEL_*` environment variables:
  +The [Knapsack](https://github.com/ArturT/knapsack) ruby gem has built-in support for the `BUILDKITE_PARALLEL_JOB` and `BUILDKITE_PARALLEL_JOB_COUNT` environment variables:
   
  -* [Knapsack](https://github.com/ArturT/knapsack)
  -<br>A ruby gem for that will automatically divide your tests between parallel jobs, as well as making sure each job runs in comparable time. Supports RSpec, Cucumber and Minitest.
  +Knapsack is a ruby gem for automatically dividing your tests between parallel jobs, as well as making sure each job runs in comparable time. It supports RSpec, Cucumber, and Minitest.
   
   ## Isolated jobs
   
  
positive.code: # Parallelizing Builds
  
  Running build jobs in parallel is a simple technique to decrease your build’s total running time. This guide will show you how to use Buildkite’s support for multiple agents and job parallelism to increase the speed of your builds.
  
  <%= toc %>
  
  ## Running multiple agents
  
  The Buildkite agent support the running of multiple instances on the one machine, as well as scaling your agents horizontally across any number of machines and networks.
  
  Each platform’s [install instructions](/docs/agent/installation) has details for how to run multiple agents on a machine. In this case we'll use the [Ubuntu-based build agent](/docs/agent/ubuntu) to start 5 instances of the Buildkite agent:
  
  ```bash
  # After running the standard install instructions...
  
negative.code: 
  <%= image 'parallelism.png', size: '555x138', alt: 'Step parallelism field' %>
  
  Update the name of the step to use `%n`, like the example below. This will substitute a number in at runtime so that you can differentiate the different build jobs:
  
  <%= image 'name.png', size: '555x80', alt: 'Step name field with %n' %>
  
  Now that the pipeline is configured, create a new build:
  
  <%= image 'build.png', size: '405x204', alt: 'The build' %>
  
  