Pick why you are writing. Get the right address.
Three kinds of message, three addresses. Choose your reason to see where to send it and what to include, so the first reply can be an answer.
Why are you writing?
Write to hello@developertoolkit.ai
A guide is wrong, or something else
Write to
Email about a guideInclude in your email
- The address of the guide and the last-updated date it shows
- The exact line that is wrong
- The tool and its version, for example the output of
codex --version - What you expected, and where you checked:
--helpor the vendor’s docs
Prefer to report in public? Open an issue on GitHub (opens in a new tab), where corrections are tracked. The guides themselves are not open source.
Billing, access or a download
Write to
Email supportInclude in your email
- The email address you signed up with
- The product (Toolkit or Team Toolkit) and the date of the payment, if it is about money
- For a download: the book, the format (EPUB or PDF) and the language
- What you saw, and a screenshot of any error
A refund is one email. A first purchase is refundable for 30 days, for any reason. Email this address and it is refunded. Polar, the merchant of record, sends a VAT invoice for every charge.
A team or org rollout to scope
Write to
Email about a rolloutInclude in your email
- How many engineers, in how many teams
- Which tools they use: Claude Code, Codex, Cursor
- Where the code and the CI live
- What should be different when it works, and your Tech Lead Scorecard or C-Level Scorecard result if you took one
Only need seats? The Team Toolkit is $299.99 once, for up to 10 people for 12 months, on one company invoice: you plus up to 9 people you add by email address. For work on your repository, see Services for teams, delivered personally by the author. Prefer to talk first? Book a short call (opens in a new tab).
Other ways to connect.
Ask in the Discord and other readers can see the answer too.
Who you are writing to
- Legal entity
- Wondel.ai sp. z o.o.
- Address
- Twarda 18, 00-105 Warsaw, Poland
- Registration
- KRS 0001029516 NIP 5252951298 REGON 524989057
30 days to find out.
The Toolkit opens the guides, the Setup Pack and all eight books for 12 months. A first purchase is refundable for 30 days.
$59.99 once for 12 months of access. Nothing renews on its own. 30-day refund on a first purchase.