Programming reference book for a publisher
Wrote a regular expressions pocket reference for a technical publisher, earning ongoing royalties.
At a glance
Estimated by a classifier that read the source. The bar shows how sure it was.
- Category
- Physical productsLow confidence53% surex
- Earns from
- SubscriptionsLow confidence50% surex
- Startup cost (estimate)
- Under $100Low confidence45% surex
- Time it takes (estimate)
- Hands-off94% surex
- Where
- Online95% surex
- Coding
- No coding needed81% surex
Source
Hacker NewsComment by tonystubblebine in “Ask HN: What is your passive income 2019?”, October 29, 2019
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