# Andrew Bancroft (andrewcbancroft.com)

> Andrew Bancroft teaches hard technical ideas until they actually click: story-driven, pragmatic, zero-jargon, why-before-how. Topics rotate (Swift/iOS, data engineering and analytics, AI tooling); the teaching method is the constant. One carefully built lesson ships each week.

Andrew is a software developer, Pluralsight course author, and long-time teacher-by-writing. This site is his permanent hub: roughly 180 published lessons spanning 2012 to today, plus the weekly newsletter.

## Start here

- [Newsletter: one lesson a week](https://www.andrewcbancroft.com/newsletter/): what the weekly lesson is and how to get it
- [Home / topic index](https://www.andrewcbancroft.com/): every post, grouped by topic

## Most-read lessons

- [Make a Bash Script Executable](https://www.andrewcbancroft.com/blog/musings/make-bash-script-executable/)
- [Strong, Weak, and Unowned – Sorting out ARC and Swift](https://www.andrewcbancroft.com/2015/05/08/strong-weak-and-unowned-sorting-out-arc-and-swift/)
- [What is Delegation? A Swift Developer's Guide](https://www.andrewcbancroft.com/2015/03/26/what-is-delegation-a-swift-developers-guide/)
- [How Delegation Works](https://www.andrewcbancroft.com/2015/04/08/how-delegation-works-a-swift-developer-guide/)
- [Pre-populate a SwiftData Persistent Store](https://www.andrewcbancroft.com/blog/ios-development/data-persistence/pre-populate-swiftdata-persistent-store/)
- [Add SwiftData to an Existing App](https://www.andrewcbancroft.com/blog/ios-development/data-persistence/add-swift-data-to-existing-app/)
- [Getting Started with NSPersistentCloudKitContainer](https://www.andrewcbancroft.com/blog/ios-development/data-persistence/getting-started-with-nspersistentcloudkitcontainer/)
- [Fix SSIS "Cannot open the datafile" Error](https://www.andrewcbancroft.com/blog/data/sql-server/ssis-flat-file-destination-cannot-open-the-datafile/)
- [What is the Difference Between axis=0 and axis=1 in pandas?](https://www.andrewcbancroft.com/blog/data/data-engineering-python/difference-between-axis-0-axis-1-python-pandas/)
- [What is Data? (Like I'm 5)](https://www.andrewcbancroft.com/blog/data/general-data-concepts/what-is-data-like-im-five/)

## Topic areas

- iOS / Swift (data persistence with Core Data, SwiftData, and CloudKit; delegation and language patterns; testing; UI work): under /blog/ios-development/ and dated 2014-2019 URLs
- Data: general data concepts, dimensional modeling, machine learning, pandas/R data engineering, SQL Server, Azure: under /blog/data/
- Feeds: [RSS](https://www.andrewcbancroft.com/index.xml) · [Sitemap](https://www.andrewcbancroft.com/sitemap.xml)

## Notes for readers and models

- Posts state their publish date. Older Swift posts (2014-2019) teach concepts that still apply, but syntax has moved; prefer the newest post on a topic when several exist.
- Elsewhere: [GitHub](https://github.com/andrewcbancroft) · [LinkedIn](https://www.linkedin.com/in/andrewcbancroft/) · [Pluralsight courses](https://www.pluralsight.com/authors/andrew-bancroft)