Black Magic Lab Cheatsheet
Cheatsheets, calculators, architecture designer, regex builder, and a GUI wizard — all offline. Press ⌘K to fly anywhere.
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Power-user shortcuts
- / or ⌘K — universal search palette
- g then o/a/k/c/f/t/d/w/r/b — jump to section (o=Obs, a=Auto, k=K8s, c=Cloud, f=Firewall, t=Tools, d=Designer, w=Wizard)
- t — cycle theme · ? — full shortcut overlay
- Star any snippet to bookmark it (saved locally only)
Calculators & Decoders
Twelve interactive utilities — all run locally in your browser.
IPv4 CIDR
IPv6 CIDR
/64 ← single LAN (default) /56 ← 256 LANs (typical site) /48 ← 65 536 LANs (enterprise) fc00::/7 ULA (private) fe80::/10 link-local ff00::/8 multicast
SLO / Error budget
Burn-rate alerting (MWMBR)
Google SRE Workbook §5 — multi-window multi-burn-rate.
Availability table
JWT decoder
Base64
URL & Hex
Cron expression
Regex Builder — guided generator
Tester (live)
YAML
JSON
ID generator
Hash
Timestamp
Color converter
Architecture Designer
Live Mermaid + D2 editor with 20 reference architectures. Edit the text on the left, see the diagram on the right. Export PNG/SVG. Each template has inline comments explaining its purpose and components.
Templates ()
GUI Builder Wizard
Step-through planning for any new infra / software / automation project. Walks you through the priority order architects use, then outputs a tailored checklist + recommended diagram + commands.
Generated plan
Project:
Quick Reference
CIDR table, ports, availability matrix — at-a-glance.
CIDR / Subnet table (IPv4)
Well-known ports
Availability table
Private / reserved IP ranges
RFC1918 private: 10.0.0.0/8 172.16.0.0/12 192.168.0.0/16
RFC6598 CGNAT: 100.64.0.0/10
RFC3927 link-local: 169.254.0.0/16
Loopback: 127.0.0.0/8
Multicast: 224.0.0.0/4
Reserved: 240.0.0.0/4
IPv6 link-local: fe80::/10
IPv6 ULA: fc00::/7
IPv6 multicast: ff00::/8
IPv6 loopback: ::1/128
IPv6 global unicast 2000::/3Cloud subnet reserved IPs
AWS VPC subnet: 5 reserved per subnet (.0 network, .1 router, .2 DNS, .3 future, .last broadcast)
Subnet sizes: /16 (largest) → /28 (smallest, 11 usable hosts)
Azure VNet: 5 reserved per subnet (.0 .1 .2 .3 .last)
Special subnets must be named: GatewaySubnet, AzureFirewallSubnet, AzureBastionSubnet
GCP VPC: No 5-reserved rule. 4 reserved: network (.0), gateway (.1), .2nd-to-last, broadcast (.last)
Subnets are regional. Primary + secondary IP ranges (alias IP).
K8s typical: Pod CIDR 10.244.0.0/16 (262 142 IPs — sufficient for ~250 nodes × 256 pods)
Service CIDR 10.96.0.0/12 (1 048 574 IPs — typically /16 is fine: 10.96.0.0/16)AI Assistant
Chat with any OpenAI-compatible LLM (Ollama, llama.cpp, vLLM, BML API). Ask about syntax, when/where to use a command, or to explain a snippet — answers are grounded in this cheatsheet via RAG.
Remote engine — CORS: for Ollama, start it with
OLLAMA_ORIGINS="*" ollama serve. For llama.cpp use --host 0.0.0.0 --port 8080.
From phone: point endpoint at your host's LAN IP (e.g. http://192.168.0.107:11434/v1).
Ask me anything about the cheatsheet
Syntax · what a flag does · when to use a tool · explain a snippet line by line.
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