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Case studyBuilding an enterprise AI platform: permission-aware RAG that holds up in production

A reference architecture for retrieval, orchestration, serving, governance, and AI operations, built around a fictional manufacturer and the production incidents that shaped it.

Case studyHow I built a governed dependency pipeline: no package ships until it earns trust

I built a quarantine-to-approved npm pipeline that scans every requested package, judges it with a tested Open Policy Agent policy, and keeps evidence for every decision. It blocked a vulnerable lodash version before any developer could install it.

PythonScore match quality and load results into Postgres

Use eval/score.py to compute precision, recall, and F1 for a reconciliation run against the ground_truth.json answer key, then optionally load the same run into a Postgres target schema.

PythonReconcile ERP and CRM records with the pipeline

Run the reconcile CLI to ingest, clean, validate, and resolve ERP and CRM exports into a single crosswalk, quarantine log, and Markdown reconciliation report.

PythonCustomize messiness and build a reproducible configuration file

Tune the missing-value, bad-date, encoding, duplicate, orphan, and amount-drift ratios that control how messy a generated dataset is, and save your choices to a config file datagen can replay exactly.

PythonCompare ERP and CRM field mappings and the ground truth answer key

Read the same customer, invoice, and payment across a flat ERP CSV export and a nested CRM JSON export, and learn what the ground_truth.json answer key does, and doesn't, record.

PythonGenerate a synthetic ERP and CRM dataset

Use the datagen CLI to produce a reproducible, deliberately messy ERP and CRM export pair, complete with a ground-truth answer key, the foundation every reconciliation lesson in this series runs against.

PythonTest model output with deterministic rules

Add deterministic rule checks to a prompt-evaluation workflow, then measure exactly where simple substring rules produce false positives and false negatives.

PythonBenchmark retrieval quality

Turn six labeled retrieval questions into a repeatable BM25 quality report using Hit@k, Recall@k, and mean reciprocal rank, then use the report to find what lexical retrieval misses.

PythonMerge rankings with Reciprocal Rank Fusion

Combine BM25 and vector rankings with Reciprocal Rank Fusion, promoting chunks found by multiple retrievers without ever comparing their incompatible raw scores.

PythonBuild and search a vector index

Build a small exact vector index that stores L2-normalized vectors, ranks results by cosine similarity, and rejects vectors from an incompatible model or dimension.

PythonImplement Okapi BM25 from scratch

Build the keyword-ranking function behind a local retrieval pipeline: preserve identifiers, calculate Okapi BM25 scores, and return deterministic ranked results without a search library.

PythonChunk Python and Markdown for retrieval

Build the ingestion pipeline that splits Python and Markdown files into stable, citable chunks, the foundation every retrieval guide in this series searches.

data scienceLesson 1: A Step by Step Guide in Passing Data to Excel and Generating a Pie Chart using Python 3.7, Openpyxl and Pandas.

Hello and welcome to this Python and Pandas tutorial series, my name is Henry Mbugua and I will be taking you through the various aspects and new answers of how to pair Python and Excel which unlocks powerful tools that not only reduce your workload but also allow you to do more by helping your […]

Vue.jsLesson 3: A Step by Step Tutorial on How to use V-for directive and render data in an HTML page by Consuming Nasa Neows API using Vue.js Framework 2.6 and Axios.js Promise Based Http Client

Hello and welcome to this Vue js tutorial series, my name is Henry Mbugua, I will be taking you through the various aspects, and new answers of how to consuming Nasa Open APIs using Vue.js and Axios.js which is a promise-based HTTP client for browsers and node.js, Vue.js is a progressive JavaScript Framework for building […]

Vue.jsLesson 2: A Step by Step Tutorial on How to Refactor Our Vue.js Code and usage of Vue.js dev tools extension in Consuming Nasa Open API using Vue.js Framework 2.6 and Axios.js Promise Based Http Client

Hello and welcome to this Vue js tutorial series, my name is Henry Mbugua, I will be taking you through the various aspects, and new answers of how to consuming Nasa Open APIs using Vue.js and Axios.js which is a promise-based HTTP client for browsers and node.js, Vue.js is a progressive JavaScript Framework for building […]

Vue.jsLesson 1: A Step by Step Tutorial on How to Consume Nasa Open APIs Using Vue.js Framework 2.6 and Axios.js Promise Based Http Client

Hello and welcome to this Vue js tutorial series, my name is Henry Mbugua, I will be taking you through the various aspects, and new answers of how to consuming Nasa Open APIs using Vue.js and Axios.js which is a promise-based HTTP client for browsers and node.js, Vue.js is a progressive JavaScript Framework for building […]

Laravel web frameworkLesson 4: A Step by Step Tutorial on How to Register Validation and Confirmation URL’s Integration to M-PESA API Using Laravel 6.9 and PHP 7.3

Hello and welcome to this PHP/Laravel tutorial series, my name is Henry Mbugua, I will be taking you through the various aspects, and new answers of M-PESA integration using Laravel web framework and PHP 7.3. Laravel is one of the most popular PHP frameworks and can help you build the application from ground up with […]

Mpesa IntegrationLesson 3: A Step by Step Tutorial on How to develop C2B Integration to M-Pesa on Daraja Using Laravel 6.9 and PHP 7.3

Hello and welcome to this PHP/Laravel tutorial series, my name is Henry Mbugua, I will be taking through the various aspects and new answers of M-Pesa integration using Laravel web framework and PHP 7.3. Laravel is one of the most popular PHP frameworks and help you build an application from ground up with expressive, elegant […]

Laravel web frameworkLesson 2: A Step by Step Tutorial on How to develop an STK push Integration to M-PESA API Using Laravel 6.9 and PHP 7.3

Hello and welcome to this PHP/Laravel tutorial series, my name is Henry Mbugua, I will be taking you through the various aspects, and new answers of M-PESA integration using Laravel web framework and PHP 7.3. Laravel is one of the most popular PHP frameworks and can help you build an application from ground up with […]

Mpesa IntegrationLesson 1: A Step by Step Tutorial on How to Integrate to Safaricom Mpesa API using Laravel 6.9 and PHP 7.3

Hello and welcome to this PHP/Laravel tutorial series, my name is Henry Mbugua and I will be taking you through the various aspects and new answers of M-pesa Integration using Laravel web framework and PHP 7.3. Laravel is one the most popular php framework and can help you build php application from ground up with […]

Task SchedulerA Step by Step Guide on How to Send Automated Email, attach a PDF Document Using Laravel Task Scheduler in Laravel 6.5 and PHP 7.3

Hello and welcome to this PHP/Laravel tutorial series, my name is Henry Mbugua and I will be taking you through the various aspects and new answers of how to build an automated workflow of sending emails in Laravel 6.5. We will also learn how we can generate a pdf document using DOMPDF wrapper for Laravel. […]

USSDLesson 2: A Step by Step Tutorial on How to Create a USSD Menu Business Logic Using Africa’s Talking Gateway in Laravel 5.8 and PHP 7.2.10

Hello and welcome to this PHP/Laravel tutorial series, my name is Henry Mbugua and I will be taking you through the various aspects and new answers of how to build real-time interactive text-based solutions that can be accessed on every type of mobile phone, including feature phone, thus a USSD menu. Every time you dial […]

Django web frameworkLesson 3: A Step by Step Tutorial on How to connect our Github Repository with Travis CI in Test-Driven Development Using Django 2.2 and Python 3.7.

Hello and welcome to this Python/Django tutorial series, my name is Henry Mbugua and I will be taking you through the various aspects and new answers of how to build better software using Test Driven Development. In lesson 2, we created a new Django project and we also learned that we are going to develop […]

USSDLesson 1: A Step by Step Tutorial on How to Create a USSD Menu Using Africa’s Talking Gateway in Laravel 5.8 and PHP 7.2.10

Hello and welcome to this PHP/Laravel tutorial series, my name is Henry Mbugua and I will be taking you through the various aspects and new answers of how to build real-time interactive text-based solutions that can be accessed on every type of mobile phone, including feature phone, thus a USSD menu. Every time you dial […]

Django web frameworkLesson 2: A Step by Step Tutorial on How to Create a Blog Application in Test-Driven Development Using Django 2.2 and Python 3.7.

Hello and welcome to this Python/Django tutorial series, my name is Henry Mbugua and I will be taking you through the various aspects and new answers of how to build better software using Test Driven Development. In lesson 1, we learned why it is important to use test-driven development. In this lesson, we are going […]

Django web frameworkLesson 1: A Step by Step Tutorial on How to Use Test Driven Development When Developing Applications Using Django 2.2 and Python 3.7.

Hello and welcome to this Python/Django tutorial series, my name is Henry Mbugua and I will be taking you through the various aspects and new answers of how to build better software using Test Driven Development. Developing an application is very difficult, even for a medium-size project which have many moving parts. Software developers are […]

Django web frameworkLesson 6: A Step by Step Tutorial on How to Fix Bug on Registering Confirmation and Validation URL’s to M-Pesa C2B Integration on Daraja Using Django 2.2 and Python 3.7

Hello and welcome to this Python/Django tutorial series, my name is Henry Mbugua and I will be taking you through the various aspect and new answers of M-pesa Integration using Django web framework and Python 3.7. In lesson 5, we learned how to register confirmation and validation URL’s, however, we had some challenges with getting […]

Django web frameworkA Step by Step Tutorial on How to Monitor Software Errors in Real-Time Using Sentry in Django Web Applications.

Hello and welcome to this Python/Django tutorial series, my name is Henry Mbugua and I will be taking you through the various aspects and new answers of monitoring applications that help all software development teams to discover and prioritize errors in real-time using Sentry. Application Error Problem Statement Most software developers rely mostly on error […]

Mpesa IntegrationLesson 5: A Step by Step Tutorial on How to Register Confirmation and Validation URL’s to M-Pesa C2B Integration on Daraja Using Django 2.2 and Python 3.7

Hey and welcome to this Python/Django tutorial series, my name is Henry Mbugua and I will be taking you through the various aspect and new answers of M-Pesa Integration using Django web framework and Python 3.7. In lesson 4, we learned how to prepare our Mpesa model and running migrations, in this lesson we are […]

Mpesa IntegrationLesson 4: A Step by Step Tutorial on How to develop C2B Integration To M-Pesa On Daraja Using Django 2.2 and Python 3.7

Hey and welcome to this Python/Django tutorial series, my name is Henry Mbugua and I will be taking you through the various aspect and new answer of M-pesa Integration using Django web framework and Python 3.7. In lesson three we learned how to develop an STK push integration, in this lesson we are going to […]

Django web frameworkLesson 3: A Step by Step Tutorial on How to do STK Push Integration To M-Pesa On Daraja Using Django 2.2 and Python 3.7

Hey and welcome to this Python/Django tutorial series, my name is Henry Mbugua and I will be taking you through the various aspect and new answer of M-pesa Integration using Django web framework and Python 3.7. In lesson two we learned how to generate mpesa token, in this lesson we are going to learn how […]

Mpesa IntegrationLesson 2: A Step by Step Tutorial on How to Generate Mpesa Access Token Using Django 2.2 and Python 3.7.

Hey and welcome to this Python/Django tutorial series, my name is Henry Mbugua and I will be taking you through the various aspect and new answer of M-pesa Integration using Django web framework and Python 3.7. In lesson one, we learned the importance of having Mpesa developers account, in this lesson we are going to […]

Mpesa IntegrationLesson 1: A Step by Step Tutorial on How to Integrate to Mpesa API Using Django 2.2 and Python 3.7

Hey and welcome to this Python/Django tutorial series, my name is Henry Mbugua and I will be taking you through the various aspect and new answer of M-pesa Integration using Django web framework and Python 3.7. Django is a powerful Python web framework that can help you develop web applications quickly, from a simple prototype […]

Django web frameworkLesson 4: A Step by Step guide on Showing Registered Users, activating & deactivating users in Django 2.2 and Python 3.7

Hello and welcome to this Python 3.7 and Django 2.2 tutorials, my name is Henry Mbugua and I will be taking through the various aspects of how to show a list of registered users, activating and deactivating users in Django. In our previous lessons, we learned how to create a custom dashboard and we are […]

Django web frameworkLesson 3. A Step by Step guide on Creating Custom Dashboard and Login User in Django 2.2 and Python 3.7.

Hello and welcome to this Python 3.7 and Django 2.2 tutorial series, my name is Henry Mbugua and I will be taking you through the various aspect and new answer of how to create a custom dashboard, redirect users to this custom dashboard after register and to login user. In our previous tutorial, we learned […]

Django web frameworkLesson 2: A Step by Step Guide on How to Use Bootstrap and Register User in Django 2.2 Authentication System and Python 3.7

Hello and welcome to this Python 3.7 and Django 2.2 tutorial series, my name is Henry Mbugua and I will be taking you through the various aspect and new answer of how to use the Bootstrap front-end framework in Django, and register a user. In our previous tutorial, we learned how to set up a […]

Django web frameworkLesson 1: A Step by Step Guide on How To Use Django 2.2 Authentication System and Python 3.7

Hello and welcome to this Python 3.7 and Django 2.2 tutorial series, my name is Henry Mbugua and I will be taking you through the various aspects and new answers of this Django python framework and specifically, the Django authentication system. Django comes with a built-in authentication framework that takes care of registering users, associate […]

Version ControlA Step by Step guide on how to use Gitflow in Software Development

Introduction Hello and welcome to a step by step guide on how to use Gitflow. In this lesson, we are going to learn what is Gitflow, why it’s important to software developers and how to use it. My name is Henry and let’s learn how to use Gitflow. What is Gitflow In our step by […]

data scienceLesson 1: A Step by Step Guide to Learning Data Science Using Python

Hello and welcome to this Python and data science tutorial series, my name is Henry Mbugua and I will be taking you through the various aspect and new answers to this data science tutorial series. The first thing we are going to cover is to understand what is data science. What is Data Science? Data […]

gitA Step by Step guide on how to use Git and Github

Introduction Hello and welcome to a step by step guide on how to use Git and Github. In this lesson, we are going to learn what is Git, why it’s important to software developers and how to use it. My name is Henry and let’s learn how to use Git. What is Git? Git in […]

Laravel web frameworkPart X: Displaying Our Posts to Site Visitors in Laravel 5.7 and Php 7.2

Hello and welcome to this tutorial series, my name is Henry and I will be taking you through the various aspect of creating a simple blog system using Laravel web framework. In lesson IX, we completed working on our admin dashboard. In this lesson, we are going to work on our landing page. When you […]

beautifulsoup4Learn How to Do Web Scraping Using Python 3.7 and Beautiful Soup 4

Introduction Hello and welcome to this tutorial, my name is Henry and I will be talking you through the various aspect of web scraping using Python 3.7 and Beautiful Soup 4. There are more than 150 million active websites today and finding relevant, comprehensive and apt information has a pivotal role to play in business, […]

blogPart IX: How to Delete a Post and Final Admin Dashboard Touch in Laravel 5.7 and Php 7.2

Hello and welcome to this tutorial series, my name is Henry and I will be taking you through the various aspect of creating a simple blog system using Laravel web framework. In Part VIII, we learnt how to edit and update our post. In this Lesson, we are going to learn how to delete a […]

blogPart VIII: How to Edit and Update Our Post in Laravel 5.7 and Php 7.2

Hello and welcome to this tutorial series, my name is Henry and I will be taking you through the various aspect of creating a simple blog system using Laravel web framework. In Part VII we learned how to upload and display an image. In this lesson, we are going to learn how to edit and […]

blogPart VII: How to Upload Image in Our Blog Application Using Laravel 5.7 and Php 7.2

Hello and welcome to this tutorial series, my name is Henry and I will be taking you through the various aspect of creating a simple blog system using Laravel web framework. In part VI we were able to store a blog post in our database. In this lesson, we are going to add the ability […]

blogPart VI: How to store and Retrieve a Blog Post in Laravel 5.7 and Php 7.2

Hello and welcome to this tutorial series, my name is Henry and I will be taking you through the various aspect of creating a simple blog system using Laravel web framework. In part V of this tutorial series, we created a form to create a post. In this lesson, we are going to learn how […]

blogPart V: Running Our Blog Migration and Creating Blog Post in Laravel 5.7 and Php 7.2

Hello and welcome to this tutorial series, my name is Henry and I will be taking you through the various aspect of creating a simple blog system using Laravel web framework. In part IV of this tutorial series, we created our blog migration. We pick from that and learn how to run our blog migration […]

blogPart IV: Creating Blog Migration and Showing Registered Users in Our Admin Portal Using Laravel 5.7 and Php 7.2

Hello and welcome to this tutorial series, my name is Henry and am really excited to continue building our blog application using Laravel 5.7. In part III of this tutorial series, we managed to set up our admin portal using Bootstrap 4. In part three, we had a task of querying the registered users and […]

blogPart III: Using Bootstrap 4 on our Blog Admin Dashboard in Laravel 5.7 and Php 7.2

Hello and welcome to part III of this tutorial series, my name is Henry Mbugua and am really excited to continue building our blog application using Laravel 5.7. In part II of this tutorial series, we managed to register a user and logged in our default admin dashboard The next step in this tutorial is […]

blogPart II: Creating Blog Admin Portal Using Laravel 5.7 and Php 7.2

Hey and welcome to this Laravel tutorial series, my name is Henry Mbugua and I will be taking you through the various aspect of creating a blog in Laravel 5.7 web framework and Php 7.2. In part I of this tutorial series, we managed to set-up our Laravel blog project and we are going to […]

DeveloperPart II: How to Sign up User and Send confirmation Email in Django 2.1 and Python 3.6

Hello and welcome to the second part of this tutorial series, I am really excited to continue with this tutorial series. In part one, we were able to setup our django project and we are going to continue from there. Here is the link to part one of this tutorial series. Creating Django Application We […]

DjangoPart I: Email verification upon sign up in Django 2.1 and Python 3.6

Hello and welcome to this python, django tutorial series. My name is Henry Mbugua and I will be taking you through the various aspect of signing up a new user and ask them to confirm that they own or control the email address used during sign up, by sending a confirmation email to activate there […]

blogPart 1: Building A Blog Application Using Laravel 5. 7 and Php 7.2

Welcome to the first section of this tutorial series, building a blog application. In the course of this tutorial series, we will be learning the following: Registering and login users. Admin control panel to manage posts and users. Uploading Image. User commenting on posts. Assumption Laravel 5.7 has a few system requirements and in this […]

DeveloperHow to Become a Better Software Developer – Our Thought

Hello and welcome to Hlab, in this post we are going to answer a question that has been asked a lot. The question has been asked in various ways including but not limited to: How can I become a better developer? What should I build? Do you have any demo project that I can build? […]

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41 active topics

08AI→01AI governance→01beautifulsoup4→09blog→02Case study→01Chunking→05Data Engineering→03Data Quality→02data science→02Developer→01DevSecOps→02Django→16Django web framework→01Enterprise architecture→02Entity Resolution→01ETL→01git→01github→01Inspirational→17Laravel web framework→01Model Evaluation→06Mpesa Integration→01Open Policy Agent→09PHP→01PostgreSQL→26Python→07RAG→01Rank Fusion→01Retrieval Evaluation→01scraping→01Search Algorithms→01Sentry→01Supply chain security→02Synthetic Data→03System Integration→01Task Scheduler→02USSD→01uv→01Vector Search→03Version Control→03Vue.js→

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