Chaos test your Kubernetes cluster.

Like Heisenberg's uncertainty principle — but for your infrastructure. Observe the bugs that only appear when you're not looking.

Get Started View on GitHub

bash — heisensim run

$ heisensim run --namespace demo --seed 42 --duration 2m

  ██╗  ██╗███████╗██╗███████╗███████╗███╗   ██╗███████╗██╗███╗   ███╗
  ██║  ██║██╔════╝██║██╔════╝██╔════╝████╗  ██║██╔════╝██║████╗ ████║
  ███████║█████╗  ██║███████╗█████╗  ██╔██╗ ██║███████╗██║██╔████╔██║
  ██╔══██║██╔══╝  ██║╚════██║██╔══╝  ██║╚██╗██║╚════██║██║██║╚██╔╝██║
  ██║  ██║███████╗██║███████║███████╗██║ ╚████║███████║██║██║ ╚═╝ ██║
  ╚═╝  ╚═╝╚══════╝╚═╝╚══════╝╚══════╝╚═╝  ╚═══╝╚══════╝╚═╝╚═╝     ╚═╝

The Experiment

🎯

Deterministic Replay

Same seed = same faults = same results. Every bug is perfectly reproducible.

🔍

Auto-Discovery

Scrapes K8s pods and health probes automatically. Zero CRDs, zero config.

💥

Fault Injection

Pod crashes, network latency, partitions. Real infrastructure failures, controlled.

📊

Timeline Correlation

Microsecond-precision mapping of faults to probe failures.

🔬

Explore Mode

Run 50 seeds in parallel. Find the interesting failures automatically.

🛡️

Property Checking

Verify SLA invariants: recovery time, availability, error budgets, cascade detection.

The Hypothesis → The Proof

Define properties in TOML. heisensim evaluates them after every chaos test. Exit code 1 when they fail — CI-friendly.

properties.toml

[[properties]]
name = "fast-recovery"
type = "recovery_time"
max_seconds = 30

[[properties]]
name = "high-availability"
type = "availability"
min_percent = 99.0

verdict

╔═══════════════════════════════════════════════════════════════╗
║  PROPERTY RESULTS                                  4/5 PASS   ║
╠═══════════════════════════════════════════════════════════════╣
║  ✅ PASS  fast-recovery      recovery < 30s (actual: 8.2s)    ║
║  ❌ FAIL  high-availability  avail ≥ 99% (actual: 94.2%)      ║
║  ✅ PASS  bounded-errors     max 5 consecutive (actual: 2)    ║
║  ✅ PASS  no-cascade         no cascading failures            ║
║  ✅ PASS  low-latency        p99 < 500ms (actual: 230ms)      ║
╚═══════════════════════════════════════════════════════════════╝

Peer Review

Feature	heisensim	Chaos Monkey	Litmus	Chaos Mesh	Gremlin
SLA Property Checking	✅	❌	❌	❌	❌
Deterministic Replay	✅	❌	❌	❌	❌
Auto-Discovery	✅	❌	⚠️	⚠️	❌
Zero-CRD CLI	✅	❌	❌	❌	❌
Fault↔Failure Correlation	✅	❌	❌	❌	❌
Open Source	✅	✅	✅	✅	❌

Lab Setup

Homebrew

brew install heisensim/tap/heisensim

Nix

nix run github:heisensim/heisensim

Cargo

cargo install heisensim