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Integrations that fix themselves

AI Tinkerers Prague · June 12, 2026 · Daniel Marchuk

Slides

https://www.figma.com/deck/0UwNQfQZBFpqpgJmqJRYqZ

Demo video

https://youtu.be/3jNjtEeP8hY

How PostHog works

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Django Migrations without Downtime

The following instructions describe a set of processes allowing you to run Django database migrations against a production database without having to bring the web service down.

Note that in the below instructions, migrations are all run manually at explicit points, and are not an automatic part of the deployment process.

Adding Fields or Tables

Adding a (nullable) field or a new table

1. Make the model or column addition in your code.

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# extracted from http//www.naturalearthdata.com/download/110m/cultural/ne_110m_admin_0_countries.zip
# under public domain terms

country_bounding_boxes = {
    'AF': ('Afghanistan', (60.5284298033, 29.318572496, 75.1580277851, 38.4862816432)),
    'AO': ('Angola', (11.6400960629, -17.9306364885, 24.0799052263, -4.43802336998)),
    'AL': ('Albania', (19.3044861183, 39.624997667, 21.0200403175, 42.6882473822)),
    'AE': ('United Arab Emirates', (51.5795186705, 22.4969475367, 56.3968473651, 26.055464179)),
    'AR': ('Argentina', (-73.4154357571, -55.25, -53.628348965, -21.8323104794)),
    'AM': ('Armenia', (43.5827458026, 38.7412014837, 46.5057198423, 41.2481285671)),

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/** Determines if an object is freed
@param obj is the object of interest
@param freeFn is a function that frees the object.
@returns a promise that resolves to {freed: boolean, memoryDiff:number}

@author Steve Hanov <steve.hanov@gmail.com>
*/
function isObjectFreed(obj, freeFn) {
  return new Promise( (resolve) => {
    if (!performance.memory) {

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import django_filters


class CommaSeparatedValueFilter(django_filters.CharFilter):
    """Accept comma separated string as value and convert it to list.

    It's useful for __in lookups.
    """

    def filter(self, qs, value):

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# JS
find . -name '*.js' | xargs wc -l | sort -nr

# SCSS
find . -name '*.scss' | xargs wc -l | sort -nr

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BEMIT Cheatsheet

Give developers more knowledge about how the classes behave in a non-relative sense: BEM + ITCSS = BEMIT

• More Transparent UI Code with Namespaces
• BEMIT: Taking the BEM Naming Convention a Step Further

Evolution

BEM:

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#!/bin/bash

for i in `seq 1 50`;
do
   rg -F id=$i\).price;
done

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Grep string in logs

docker logs nginx 2>&1 | grep "127."

Create file from logs

docker logs nginx > stdout.log 2>stderr.log

Mac - clean docker orphaned volumes

docker volume rm $(docker volume ls -qf dangling=true)

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import csv
import requests

result = ''

for i in range(195):
    list_json = requests.get(url, headers={
        'X-Requested-With': 'XMLHttpRequest',
        'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_13_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36',
        'Accept': '*/*',