Plans

Buy the course. Keep the course.

Free articles stay free forever. Courses are bought one at a time, once — and the parts added to them later come with it.

Free stays free
The open articles and the newsletter never need a card.
Nothing renews
One payment per course. There is no subscription to cancel.
Payments by Razorpay
Card details go to the gateway, never to us.
  • Free reading

    No card needed

    The open archive, the newsletter, and the opening part of every course.

    • Every free article, in full
    • The weekly newsletter
    • The first part of every course
    • Guidebook announcements
  • Most people start here

    A course

    One payment

    Buy the course you want. It stays yours — there is nothing to renew.

    • Every part of that course
    • Parts added to it later, at no extra cost
    • Its guidebooks and downloads
    • Progress, bookmarks and completion

Changed your mind after buying? See the refund policy.

What changes when you buy a course

Everything a free reader has today stays exactly as it is. Each course is bought on its own.

A comparison of what a free reader gets and what buying one course adds.
CapabilityFree readerA course you own
Free articlesIncludedIncluded
The weekly newsletterIncludedIncluded
Parts of that courseThe first oneEvery part
Parts added to it laterNot includedIncluded, no extra payment
Its guidebooks and downloadsNot includedYours to keep
Progress, bookmarks and completionNot includedIncluded
How long you keep itFree articles stay openNo expiry, nothing renews
Other coursesFirst part of eachBought separately

Questions

How often does something new arrive?

A new deep dive every weekday, and a crash course finishes every few weeks. Nothing goes out that has not been read end to end by someone who works in the field.

Do I need a maths background?

Comfort with linear algebra and Python helps. Where a derivation matters we show it in full rather than pointing at a paper and moving on.

Can I read on my phone?

Yes. The reader is built for long reading on a small screen, and the newsletter carries the full article for members.

Do I keep a course after I have bought it?

Yes. There is no subscription and nothing renews — a course you have bought stays readable, and the parts added to it later come with it at no extra cost.

Does buying one course open the others?

No. Each course is bought on its own. The free articles, the newsletter and the opening part of every course stay open to everyone either way.