GasHammer

Adversarial load-testing and correctness-verification platform for Arbitrum Nitro rollup infrastructure.

GasHammer is designed to stress-test Nitro rollup deployments by generating realistic, gas-modeled transaction workloads and verifying correctness invariants under load. It interacts with Nitro exclusively through wire protocols (JSON-RPC, WebSocket feed, gRPC) without importing any Nitro internals.

Key Capabilities

• Gas-first workload modeling — workloads are defined by target gas/sec, not requests/sec. Transaction templates specify gas profiles that accurately model real-world usage patterns.
• Deterministic reproducibility — seeded PRNGs ensure that the same scenario configuration produces the same transaction sequence every time.
• Correctness verification — an oracle checks invariants (balance conservation, nonce monotonicity, gas accounting) both during and after each run.
• Fault injection — controlled network faults (latency, packet loss, partition) test resilience under adverse conditions.
• Decision-grade reporting — capacity envelopes, regression detection, and release gate verdicts provide actionable results.

Architecture at a Glance

GasHammer uses a hive/edge topology:

                    ┌──────────────┐
                    │     Hive     │  Control plane (1 instance)
                    │  REST + gRPC │  Orchestrates runs, collects telemetry
                    └──────┬───────┘
                           │ gRPC
              ┌────────────┼────────────┐
              │            │            │
        ┌─────┴─────┐┌────┴──────┐┌────┴──────┐
        │   Edge 1  ││  Edge 2   ││  Edge N   │  Workers (many instances)
        │  Region A ││ Region B  ││ Region C  │  Generate txs, collect data
        └─────┬─────┘└────┬──────┘└────┬──────┘
              │           │            │
              └───────────┼────────────┘
                          │ JSON-RPC / WebSocket
                    ┌─────┴──────┐
                    │   Nitro    │  System under test
                    │  Rollup   │
                    └────────────┘

• Hive accepts scenarios via REST API, distributes work to edges, synchronizes phases, and aggregates results.
• Edges connect to the Nitro sequencer, generate transactions at the target gas rate, and stream telemetry back to the hive.

License

GasHammer is licensed under the Business Source License 1.1 (BSL-1.1).

Next Steps

• Getting Started — install, configure, and run your first test
• Architecture Overview — understand the system design
• Scenario Authoring — write test scenarios in SDL