In this episode of Running in Production, Brendan Wood talks about building a portfolio management platform with Django and Python. It’s been running in production since mid 2017 and is hosted on DigitalOcean.

There’s about 3,000+ active users and overall they are responsible for managing hundreds of millions of dollars in funds for their users.

Topics Include

• 3:13 – It started as a 50 line Python script that replaced an Excel sheet
• 10:49 – Motivation for using Django, Python, NumPy and creating a monolithic app
• 15:38 – Eventually decommissioning a legacy version of the back-end over time
• 19:00 – There’s about 33,000+ lines of back-end code, including tests
• 22:24 – There’s a clean split between the back-end API and the TypeScript React front-end
• 30:52 – The entire front-end is open source on GitHub
• 32:13 – It’s hosted on DigitalOcean w/ Ubuntu 18.04, PostgreSQL, Redis, Celery and nginx
• 39:08 – There’s ~5 seconds of down time per deploy which is done outside of trading hours
• 46:00 – Everything runs on a single server + a managed PostgreSQL DB (with replicas)
• 48:20 – Ansible is being used to configure the server
• 55:22 – Getting code from dev to production in a few minutes with git and a deploy script
• 1:01:07 – Brendan’s philosophy on starting a business is to do things when you need to do it
• 1:02:58 – Logging, email alerts and using Stripe to handle payments
• 1:08:35 – Handling disasters and other unexpected events with backups and alerts
• 1:16:19 – Best tips? Use the tools that you know unless you have a compelling reason not to
• 1:19-27 – Setting up a customer support system only after they had a need for it
• 1:21:39 – Check out https://getpassiv.com/

Links

• https://en.wikipedia.org/wiki/Exchange-traded_fund

• django →
• python →
• react →
• ansible →
• digitalocean →
• lets-encrypt →
• nginx →
• postgres →
• redis →
• stripe →
• supervisor →
• ubuntu →
• webpack →

• https://numpy.org/
• https://github.com/encode/django-rest-framework
• https://github.com/celery/celery
• https://gunicorn.org/
• https://github.com/kakulukia/django-secrets
• https://github.com/dj-stripe/dj-stripe

Support the Show

This episode does not have a sponsor and this podcast is a labor of love. If you want to support the show, the best way to do it is to purchase one of my courses or suggest one to a friend.

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