From Snowflake Servers to GitOps Nirvana

8 open-source tools you can combine so that git push deploys your entire stack.

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🚀 Why This Exists

You’ve probably heard the buzzwords: GitOps, NoOps, immutable infrastructure.

This guide walks you step by step through:

• Why these concepts exist.
• How a small constellation of tools — Git, NixOS, Docker, Terraform, Kubernetes, Argo CD, DSPy, and OPA — fit together.
• How to create a platform that deploys itself every time you hit merge.

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🗺 Quick Tool Map (click to open)

Tool	One-Sentence Job	Why It Matters
Git	Single source-of-truth for every line of code/config.	Immutable history + pull requests = collaboration without chaos.
NixOS	An entire Linux distro expressed in one declarative file.	Reinstalls laptop or 1,000-server fleet with nixos-rebuild.
Terraform	Describe cloud resources (VPCs, disks, IAM) in HCL.	Recreates an entire region from scratch in 15 minutes after a coffee spill.
Docker	Bundle the app and its libraries into an immutable image.	Same artifact runs on your Mac, in CI, and in prod.
Argo CD	Watches Git and makes Kubernetes match it.	Manual kubectl apply becomes a pull request review.
Kubernetes	Planet-scale scheduler that keeps containers healthy.	Auto-heals, scales, and rolls out with zero downtime.
DSPy	Prompt engineering as typed, testable code.	Turns LLM prompts into reproducible pipelines.
OPA/Kyverno	Policy-as-code gatekeepers for every API call.	Blocks :latest images or unencrypted buckets before they deploy.

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❄ 1. The Problem We’re Solving

In the old world, a server was a pet:

• Lovingly hand-fed config files.
• Patched on Sundays.
• Inevitably different from every other server.

The result?

• “It works on my machine!”
• Snowflake drift and 3 a.m. pages.
• Scaling = more pets.

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⭐ 2. The North Star: Everything as Code

Instead of pets, we want cattle — identical, replaceable, and defined in text files that live in Git.

If Git is the single source of truth, the rest of the stack becomes a conveyor belt that turns that truth into running software.

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🎭 3. The Cast of Characters and Their Jobs

(See the Quick Tool Map above)

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🔗 4. How the Characters Relate

Declarative GitOps Workflow

💡 Press Ctrl + + / - (or pinch-zoom on mobile) to enlarge the diagram. Right-click to open full image in a new tab.

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🔄 5. A Day in the Life of a Change

Let’s add a new feature: real-time in-game leaderboards.

1. Code
   • Write the leaderboard service in Go.
   • Add a DSPy pipeline to pre-aggregate stats.
   • Commit everything to Git.
2. CI Gate
   • Nix builds the Docker image (bit-for-bit reproducible).
   • Terraform dry-run shows a new Redis cache.
   • Tests pass → image signed & pushed.
3. GitOps Sync
   • Argo CD detects the new commit hash.
   • Kubernetes manifests applied; pods roll out blue-green.
   • OPA policy ensures the service can’t talk to the payments DB.
4. Observe
   • Prometheus sees p95 latency drop.
   • Grafana dashboard auto-updates.

✅ No humans touched a server.

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🏁 6. Beginner Takeaways

• Start small: Put one service in Docker, store its manifest in Git, and let Argo CD sync it.
• Lean on NixOS for dev laptops — nix develop gives the exact same tools as prod.
• Policies early: A 15-line OPA rule today prevents a 3 a.m. breach tomorrow.
• Celebrate merges: Every green PR is a fully tested, policy-compliant, zero-downtime release.

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📦 Grab the Configs

File	Action
README.md	⬇ Download
flake.nix	⬇ Download
main.tf	⬇ Download
argocd-app.yaml	⬇ Download
constraint-template.yaml	⬇ Download

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🌍 7. The Bigger Picture

Declarative, Git-driven stacks aren’t tools — they’re a culture. When everything is code:

• Knowledge lives in the repo, not in someone’s head.
• Onboarding is faster.
• Refactors are fearless.
• And Friday deploys don’t ruin weekends.

Welcome to the Declared World: where robots do the toil, and we get back to building great things.

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