Free LGPLv3 core; GoReplay PRO from $3,000 per year.
First released
2013
Last verified
Answer
GoReplay is a Go daemon that listens passively on network interfaces instead of sitting in the request path, so recording production traffic requires no infrastructure change beyond running the binary alongside the service. Captured traffic can be written to file, replayed against a staging environment, split across several targets, or amplified to generate load from.
About
GoReplay is a Go daemon that listens passively on network interfaces instead of sitting in the request path, so recording production traffic requires no infrastructure change beyond running the binary alongside the service. Captured traffic can be written to file, replayed against a staging environment, split across several targets, or amplified to generate load from real request mixes rather than synthetic scripts. Requests pass through optional middleware programs that read and rewrite payloads over stdin/stdout — a Node.js framework is provided and any language works — which covers token refresh, data masking, and rewriting. The LGPLv3 core handles HTTP capture and replay; GoReplay PRO adds binary protocols such as Thrift and Protocol Buffers, cloud storage of recorded traffic, TCP session replication, and data masking.
Best for
API and protocol throughput or latency campaigns
Teams that prefer open-source licensing and self-hosting options
Groups comfortable scripting in JavaScript, Go
Not the best fit when
Teams unwilling to operate generators, results storage, and scaling
Architecture and concurrency
GoReplay is commonly operated as self-hosted software with scenario authoring in JavaScript, Go. Concurrency and distribution depend on how you size workers or injectors.
Specs
Scripting
JavaScriptGo
Protocols
HTTPHTTPSTCP
Operating systems
LinuxmacOSWindows
Tags
traffic-replayshadow-testinggolang
CATALOG LAST VERIFIED · 2026-08-12
Frequently asked
ANSWER-SHAPED
Who is GoReplay for?
GoReplay is best for engineers focused on API and protocol-level throughput and latency. It is open source, so teams can self-host and extend it. Vendor: Probe Labs. Deployment model: self-hosted. Free LGPLv3 core; GoReplay PRO from $3,000 per year. Confirm details against the official site and a short proof-of-concept in your environment.
How does GoReplay differ from Artillery?
Compared with Artillery, scripting centers on JavaScript, Go rather than JavaScript, TypeScript. GoReplay lists protocols HTTP, HTTPS, TCP; Artillery lists HTTP, HTTPS, WebSocket, Socket.IO, MQTT. Status is active versus active. Use the Test Rig to compare full specs side by side before a proof-of-concept.
What scripting language and concurrency model does GoReplay use?
GoReplay uses JavaScript, Go for scripting or scenario definition. Runtime model: code-first scenarios where virtual users execute scripted behavior under load. OS support: Linux, macOS, Windows. Protocols: HTTP, HTTPS, TCP. Match these to how your team already authors tests and which systems you must drive under load.
What is the cloud or enterprise path for GoReplay?
GoReplay is primarily self-hosted; teams typically run generators on their own machines, CI runners, or private cloud. Plan for generator capacity, network access to targets, and result storage yourself. As open source, commercial support or hosted siblings may exist separately. Check the official site. Pricing note: Free LGPLv3 core; GoReplay PRO from $3,000 per year.
What are known limitations of GoReplay?
GoReplay limitations to weigh: self-hosted tools require you to provision, scale, and observe load generators yourself. Status: active. Always validate against your target protocols and scale with a proof-of-concept. Confirm details against the official site and a short proof-of-concept in your environment.