Spending $5k to learn how database indexes work

How we got here At Superwall we’re building an SDK to help App Developers increase their revenue by showing the right offer to the right person at the right time. Follow me on twitter for little tips and articles like this one. To deliver this service, we need to keep track of all of our customer’s users, the end users. To keep the numbers simple, assume we’re working with 5 companies who each have ~5k downloads a day, that’s roughly 25k downloads a day, or 750k users in a month.

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Troubleshooting Apple Captive Portal Problems

TL;DR: The Wi-Fi was blocking my custom DNS settings, so I connected on my iPhone, viewed the DNS servers that DHCP configured automatically and set the manually. Recently had the pleasure of fighting against hotel Wi-Fi. It’s a simple captive portal that only requires you to accept the TOS but could not connect to anything. First clue: I tried to curl google and got the response curl: (6) Could not resolve host: google.

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Heroku Wildcard SSL Certificate Automated Provisioning

I recently setup Heroku Wildcard SSL and it took a bit of doing so decided to post this to hopefully make someone’s day a little easier! Let’s say I have domain.com and I want to point *.domain.com to a heroku app. Additionally I use Cloudflare for DNS. Manually configure the heroku domain *.domain.com Setup the provided CNAME in cloudflare. Create a GitHub Action which runs weekly and updates the SSL certificate.

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