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Alex Booker
Mastra
@bookercodes
Building @Mastra - teaching you how to build agents along the way
London
booker.codes
Joined July 2015
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    Alex Booker
    Mastra
    @bookercodes
    Jun 10
    What's the difference between an eval and a test? Yeah, I wasn’t totally sure either... So I went deep and made Evals 101 - a short 20 minute mini-course on the fundamentals (with examples) Fair warning - evals are hard. There are lots of ideas, opinions, and best practices
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    Alex Booker
    Mastra
    @bookercodes
    Feb 10, 2022
    You don't need a Computer Science degree to become a hireable programmer. That's it. That's the Tweet.
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    Alex Booker
    Mastra
    @bookercodes
    Feb 9, 2022
    Our culture is youth-obsessed. It's always "14-Year-Old Prodigy Programmer Dreams In Code" or "16-Year-Old Dropout is CEO of Company Worth Millions" Never "28-Year-Old Person Learns to Code and Starts a Steady And Profitable Career Where They Feel Valued and Have a Life"
  • user avatar
    Alex Booker
    Mastra
    @bookercodes
    Sep 19, 2022
    Junior developers do not know their worth but I am going to convince you! Here are 9 unspoken reasons companies need juniors and why you should feel empowered to negotiate:
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    Alex Booker
    Mastra
    @bookercodes
    Apr 3, 2018
    We built an open source Slack clone complete with: 👉 Private rooms 👉 Rich media attachments 👉 Typing indicators 👉 Read receipts ... All powered by @ReactJS and Pusher Chatkit 💪 Source code: github.com/pusher/react-s…
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    Alex Booker
    Mastra
    @bookercodes
    Dec 22, 2021
    Here it is 🎉! A comprehensive (and ambitious 🥵) JUNIOR Web Developer checklist Years of experience is too vague to measure skill. I hope this template I made with @scrimba gives your SPECIFIC ideas about what to learn next 🌱! different-marmoset-f7b.notion.site/Junior-Web-Dev…
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    Alex Booker
    Mastra
    @bookercodes
    Oct 31, 2021
    CSS is a nice, relaxing way to get super frustrated and disappointed in yourself
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    Alex Booker
    Mastra
    @bookercodes
    Feb 18, 2022
    Saying JavaScript is better than PHP is like saying English is better than Spanish. Literally makes no sense. You could write the next great novel in either English or Spanish. You can write the next great app in any JavaScript or PHP.
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    Alex Booker
    Mastra
    @bookercodes
    Feb 14, 2022
    It's always, "how do I get a dev job?" Never, "how do I become a talented and collaborative developer companies *want* to work with?"
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    Alex Booker
    Mastra
    @bookercodes
    Feb 17, 2022
    I went IN-DEPTH to find the best sites to to find junior developer jobs. Made sure to include some niche ones where you can sidestep the competition 👏💯! Here you go:
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    Alex Booker
    Mastra
    @bookercodes
    Sep 23, 2025
    I saw a viral post that said “MCP is just an API” That is wrong and misleading ❌ I recorded a highly-detailed video to explain the difference and why it matters
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    Alex Booker
    Mastra
    @bookercodes
    Jan 25, 2022
    Still working out the deets but you can now look forward to a special @Scrimba space this Thursday where we will invite newer developers to share their story so far 🌱 We're all going to make a bunch of new friends and learn a lot in the process 👇🏻 🔗 x.com/i/spaces/1jMKg…
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    Alex Booker
    Mastra
    @bookercodes
    Jan 6, 2023
    How do you remember the order of padding: 10px 10px 10px 10px I always think north east south west I also heard someone picture it like a clock
    47K
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    Alex Booker
    Mastra
    @bookercodes
    Feb 23, 2022
    An interviewer asks, "what are your biggest weaknesses?" What do you say? Cliche answers only 😂👇