shipit-engine: Undefined method data for Nil GithubSyncJob

After setting up shipit on localhost, I’m trying to kick the tires to see if this is a good fit for our org. After setting up the github app, putting the various details into the configuration file and navigating to the application on localhost, whenever the app tries to sync to GitHub we see this:

2018-10-05T20:06:49.494Z 23685 TID-ovdousoy5 WARN: {"context":"Job raised exception","job":{"class":"ActiveJob::QueueAdapters::SidekiqAdapter::JobWrapper","wrapped":"Shipit::GithubSyncJob","queue":"default","args":[{"job_class":"Shipit::GithubSyncJob","job_id":"69ff00e6-882b-4cf5-89f9-879618930104","provider_job_id":null,"queue_name":"default","priority":null,"arguments":[{"stack_id":1,"_aj_symbol_keys":["stack_id"]}],"executions":0,"locale":"en"}],"retry":true,"jid":"bab64f2d1375b94bd5dea146","created_at":1538769612.748343,"enqueued_at":1538770008.6277819,"error_message":"undefined method `data' for nil:NilClass","error_class":"NoMethodError","failed_at":1538769619.032265,"retry_count":3,"retried_at":1538769840.457341},"jobstr":"{\"class\":\"ActiveJob::QueueAdapters::SidekiqAdapter::JobWrapper\",\"wrapped\":\"Shipit::GithubSyncJob\",\"queue\":\"default\",\"args\":[{\"job_class\":\"Shipit::GithubSyncJob\",\"job_id\":\"69ff00e6-882b-4cf5-89f9-879618930104\",\"provider_job_id\":null,\"queue_name\":\"default\",\"priority\":null,\"arguments\":[{\"stack_id\":1,\"_aj_symbol_keys\":[\"stack_id\"]}],\"executions\":0,\"locale\":\"en\"}],\"retry\":true,\"jid\":\"bab64f2d1375b94bd5dea146\",\"created_at\":1538769612.748343,\"enqueued_at\":1538770008.6277819,\"error_message\":\"undefined method `data' for nil:NilClass\",\"error_class\":\"NoMethodError\",\"failed_at\":1538769619.032265,\"retry_count\":3,\"retried_at\":1538769840.457341}"}
2018-10-05T20:06:49.494Z 23685 TID-ovdousoy5 WARN: NoMethodError: undefined method `data' for nil:NilClass

I set up a stack on my localhost application pointing to the appropriate github repository, and authorized the app on my account when I first viewed the app.

We have placed the GH App id, the installation id, the private key, the oauth values all into secrets.yml in the development environment.

Any idea what we’re doing wrong?