zyqzyq/Unfour

Unfour
**A unified, local-first developer workspace for tracing backend failures from API requests through server logs and database state to verified fixes.**
Unfour brings API testing, SSH, database tools, local Flow runbooks, and MCP-assisted troubleshooting into one desktop application.
> [!WARNING]
> Unfour v0.11.0 was released on 2026-10-10. Windows NSIS
> installers are unsigned and may trigger SmartScreen or other operating-system
> security warnings. Use SHA256SUMS.txt from the GitHub Release to verify
> downloaded files.
See the v0.11.0 changelog,
Release Notes, and
final release verification.
Download
Download the latest Unfour release
from GitHub Releases.
- Windows is the primary distribution path: NSIS .exe installer. It is
unsigned and may trigger SmartScreen.
- macOS has Apple Silicon and Intel packages; real-device install/run
verification was recorded for v0.9.0. They are not Apple-signed or notarized;
Gatekeeper may block them.
- Linux publishes an x86_64 (x64) AppImage only. It is Experimental and currently
targets Ubuntu 22.04+; Ubuntu 20.04 is not supported. The published v0.9.0
AppImage predates this build baseline; new-artifact runtime verification is
still pending. .deb and .rpm packages are not formally supported or
published.
- Verify downloaded installers with the release SHA256SUMS.txt asset.
What Is Unfour?
Unfour helps backend developers investigate failures that span an API, a
server, and its database. Troubleshooting is Unfour's core product loop:
reproduce an issue with an API request, inspect server logs over SSH, check
database state, identify the cause, and make and verify a fix.
A unified, local-first workspace keeps requests, connections, local activity,
and layout together throughout the investigation. API testing, SSH terminals,
and database tools provide the capabilities for each step in that loop. Flow
combines those capabilities into local runbooks for repeatable checks and tasks.
Flow V1 is local-only: its definitions and run history are not included in Cloud
Sync. It is a runbook tool for this workspace, not a general workflow platform.
MCP is an optional assisted layer: Codex and Cursor can use the local stdio
MCP server to work with the same saved API, SSH, and database connections as
the desktop app. Its workspace-scoped tools run through the shared command
bus, subject to MCP policy and high-risk action confirmation checks.
MCP can also start and cancel Flow runs and inspect their history.
Troubleshooting remains user-directed: you author and start runbooks, while
Unfour does not automatically correlate requests, logs, and database state or
detect root causes.
Unfour is one application and one product. Its core desktop features are free
and open source under Apache-2.0. An active Pro subscription unlocks Cloud Sync
in the same application. Pro is an entitlement within Unfour, not a separate
client, package, repository, or release.
The app is built with Tauri 2, React, TypeScript, and Rust. The frontend owns
the workbench UI, while security-sensitive execution such as HTTP, SSH,
database drivers, local storage, and credential references lives behind Rust
capability crates and the command bus.
Troubleshooting Workflow
The investigation stays in one workspace, while you remain in control of each
request, SSH session, query, and verification step.
For Coding Agents
Codex or Cursor can use their own repository tools to inspect, change, and test
code. Unfour complements those tools with controlled access to API behavior,
SSH/server evidence, and database state through MCP, so the agent can help
investigate the running backend and re-check it after a change.
Unfour does not edit the repository itself: the coding client owns code changes,
while Unfour provides the runtime side of the investigation. You control the
workspace, environment, risky actions, and final decision.
Modules
- **API Client** - Compose and send HTTP requests, organize saved requests into