Open source · built in public

Open source, with the details.

Every project here has public code. Most also have their own site with the architecture, docs or a write-up. Pick a tab, open a project, and read how it works.
128 public repositories, 420 stars and 611 forks on GitHub. Client systems, whose code is private, are written up under Work.github.com/codewithmuh ↗
01Delivery platform · set in Tokyo

Tasuki

Phase 1 of 7 · proven locally

The delivery side of a business, as software you run next to your own. Your system creates a delivery over the API; Tasuki quotes a price and an ETA, dispatches the nearest courier on real Tokyo roads, and streams the courier live to the customer's phone. Built to production standards: idempotent orders, a Kafka location pipeline, written SLOs, load tests and game days.

orders/h at full design scale, on one laptop
18,144
GPS points/s, with 0 failed orders
641
game-day plans; the first one run, with a postmortem
12
fig. 01orders · locations · operate
CLIENTSYour systemorders apiCouriergps · offersCustomertracking pageSimulatorplays the cityMONEY PATH · DJANGOordersidempotent · quotesPostgreSQLoutbox → relayLOCATION PATH · GOfleet-ingestgps → kafkatrackingsse · reads kafkadispatchoffers over sseKafka3 topics18,144 orders/hmeasured · one laptop641 gps/s · 0 failed ordersfleet-statenewest point / courierValkeycache · rebuilt from logOSRMtokyo roads · 23 wardsOPERATE · AP-NORTHEAST-1 · DASHED = WRITTEN, NOT YET APPLIEDEKS · KarpenterArgo CDKyvernoSLOs · burn raterollout gategame days
GoDjangoKafkaPostgreSQLValkeyOSRMReactTerraformEKSArgo CD

The company is fictional and the traffic is simulated. The EKS and GitOps layers are written and checked, not yet run on a cluster.

02Self-hosted LLMs · AWS + Google Cloud

Private LLM Chat

Public · docs site with five guides

Open-weight models (Qwen, Llama, Gemma, DeepSeek) served with vLLM on Amazon SageMaker, several per GPU, with weights from S3, an optional no-internet VPC, and a GPU that switches itself off when idle. The Django and React app streams chat and handles documents, images and voice.

open-weight model families, several per GPU
4
GPUs running when idle
→ 0
guides, from a laptop to the full AWS stack
5
fig. 02self-hosted stack
REACT APPstream · docs · images · voiceDjango APIstreaming rest · 2faWhisperOCRWeb searchSAGEMAKER · VLLMQwenLlamaGemmaDeepSeekGPUseveral models per gpuscale → 0 when idleweights from s3 · no-internet vpc optionS3 weightsofflinePrivate VPCoptionalModel Runnerlaptop · dockerTERRAFORM · ONE STACKalbcdnecssagemakerdatabasenetworkecremailcicddocs site · guides · gpu sizing · cost reference · MIT
vLLMSageMakerTerraformDjangoReactWhisperCloud Run

No production users are claimed. The Google Cloud Run port is early.

03Ecommerce growth · CRO

Cartlift

Live · v0.1

Paste a store URL and get an annotated four-lens audit (CRO, SEO, trust, Google Merchant) in about 30 seconds. Cartlift drafts variants, ships them through a 3 KB snippet, and a Thompson-sampling allocator pins the winner, so there is no dashboard to babysit.

four-lens audit of a store page
~30 s
snippet that ships the variants
3 KB
confidence, plus 500 samples, before a winner is pinned
95%
Live site & details ↗Code ↗★ 2 · ⑂ 0 · MIT
glowly.kr / products / glass-skin-serum
GLOWLYNEWSKINSHOP
★ bestseller·★★★★★12,403 reviews

Wake up with
glass skin.

$32$45

↻ free shipping over $40 · 14-day returns

cartlift · pdp headline (v3)+14.2%
~/cartlift/experiments● live
pdp · hero headline · v07+18.3%winner
checkout · button copy · v03+11.4%winner
cart · sticky upsell · v02+7.1%winner
homepage · video autoplay−2.1%killed
footer · trust + reviews+0.3%trial
conversion · 30d+38.3%
baseline 2.81%→ 3.89% ↗
cartlift · 1 winner shipped this weekv0.1.0
Next.jsDjango + DRFPostgreSQLClaudeOpenAI (BYO key)Docker Compose
04AI front desk · home services

Hearthline

Beta

An open-source AI receptionist for HVAC, plumbing, roofing and solar teams. It answers every inbound call through Vapi, qualifies the lead, books a slot, drafts a quote from a photo, and writes a structured lead into the dashboard. Self-hosted, with your own model and telephony keys encrypted at rest.

inbound calls answered and qualified
24/7
channels: phone, SMS, WhatsApp, email, web
5
UI languages, Japanese included
10
hearthline / live calls
incoming · +1 (555) 0192
A
Anna
AI receptionist · Apex HVAC
“Hi! This is Anna from Apex HVAC — how can I help you today?”
02:14 · transcribing
~/hearthline/leadwriting → postgres
nameSarah K.
serviceHVAC repair · no heat
address1142 Oak St · zone 3
slotThu 2:00 PM
quote$1,248 · drafted from photo
✓Lead qualified
✓Slot booked · Thu 2:00 PM
✓Photo quote drafted
5 channels · phone · sms · whatsapp · email · webbeta
Next.jsDjango + DRFPostgreSQLVapiTwilioClaudeOpenAI Vision
+Agents, platform builds and courses
  • 05

    AI Receptionist

    Voice agent · Open source

    A voice agent on Vapi with a Claude tool-use loop: checks the calendar, books the slot, sends an SMS, logs the call.

    Details →Code ↗★ 22 · ⑂ 10
  • 06

    AI Support Agent

    Multi-channel support · Open source

    WhatsApp, Telegram, Gmail and web chat in one inbox: Haiku triages, Sonnet answers from a pgvector knowledge base, people take over when it should.

  • 07

    AI Hiring Agent

    Recruitment screening · Open source

    Claude scores résumés against the role, a voice agent screens the strongest candidates, and Claude analyses the transcript for a person to review.

    Details →Code ↗★ 2 · ⑂ 2
  • 08

    Three-Tier DevSecOps on EKS

    Reference pipeline · Reference build

    A three-tier app delivered to EKS: Terraform, Jenkins, Argo CD GitOps, Trivy and SonarQube gates, Prometheus and Grafana.

  • 09

    AWS EKS HA platform

    Compose → three-zone EKS · Reference build

    Takes a microservices app from one Docker Compose host to a three-zone EKS platform: Terraform, a Helm library chart, Argo CD, failover drills.

    README ↗Code ↗★ 0 · ⑂ 0
  • 10

    AWS 3-tier DevOps project

    Terraform + GitHub Actions · Reference build

    A three-tier web app on AWS with Terraform and a GitHub Actions pipeline, written up step by step.

    Write-up ↗Code ↗★ 0 · ⑂ 0
  • 11

    Production repo template

    GitHub template · Template

    A GitHub template that makes a new repository production-grade from the first commit: CI on every pull request, secret and vulnerability scanning, signed images with SBOMs, automated releases.

    README ↗Code ↗★ 0 · ⑂ 0 · MIT
  • 12

    Django starter kit

    Starter · Template

    A pre-configured Django environment (DRF, Celery, Docker and Elasticsearch) that starts with one command.

    README ↗Code ↗★ 18 · ⑂ 9
  • 13

    MLOps for DevOps engineers

    11-part course · Course

    Model serving with FastAPI, an MLflow registry, DVC, EKS, Terraform, Prometheus and drift-triggered retraining, one part at a time.

    README ↗Code ↗★ 0 · ⑂ 0
  • 14

    Hack & Detect

    Security labs · Course

    Learn security by breaking things: every lab runs with one command, you attack the target, run the detection that catches it, then fix it.

    README ↗Code ↗★ 0 · ⑂ 0
  • 15

    System design

    Case studies · Course

    How large systems are actually built: clear explanations, real diagrams and full case studies.

    README ↗Code ↗★ 1 · ⑂ 0
→Built in public

A new build every few months, open from day one.

Most of these come with a build series on YouTube. Want one set up for your team, or have a problem worth building in the open?