The Declarative HTTP Client.
Write your API sequences, run them anywhere.
Flexiberry is the open-source API testing framework that chains
dependent requests sequentially using a clean, declarative language.
Zero Javascript boilerplate. Zero environment sync pain. Just readable .berry scripts that run natively from your editor, CLI, or CI/CD pipelines.
Native Framework Integrations
Generate type-safe Flexiberry workflow specs directly from your existing backend controllers, annotations, and route handlers.
How does FlexiBerry compare to
traditional API tools?
| Capability | Postman / Insomnia | Bruno / Hurl | FlexiBerry YOU |
|---|---|---|---|
| Git-friendly plain-text format Store API specs directly in repo with human-readable diffs & commits | (JSON blobs) | Yes | .berry DSL |
| Sequential request chaining w/ captures Extract tokens & variables from step N and inject into step N+1 | Scripted (JS pre/post-request) | Manual | First-class Capture / Step.N.key |
| Native readable assertions Declarative status, body, and header checks without JS test bloat | Scripted | Basic | Check block w/ OR chains |
| CLI runner Automate test sequences effortlessly in CI/CD or local terminals | Newman (separate tool) | Hurl CLI | Built-in flexiberry run |
| Editor integration Full IDE experience with diagnostics, autocomplete, and formatting | Extension-ish | VS Code ext | Full LSP (diagnostics, autocomplete, formatter) |
| Environments / scoping Dynamic variable contexts across local, staging, and production | Yes | Partial | Env + @pointer blocks |
| Data-driven loops Parameterized execution with multiple input data iterations | Yes (CSV runner) | Yes | Input statement |
| Secrets encryption Secure storage & runtime decryption of sensitive keys and tokens | Vault integration | Decrypt + pluggable provider | |
| Visual notebook-style editor Interactive block-based workspace for building, running & inspecting | N/A | Svelte block IDE Unique! |
Zero Cloud Lock-in & No JS Scripts
Replace heavy GUI apps and hidden pm.response.json() scripts with human-readable .berry files committed directly to your Git repository.
First-Class Chaining & LSP Tooling
FlexiBerry features first-class Capture syntax, native Check assertions with OR chains, secrets decryption, and full LSP autocomplete.
Interactive Svelte Block IDE
A unique visual notebook experience combining the speed of plain-text code with interactive block-based testing, instant responses, and built-in CLI execution.
API Testing shouldn't require
writing an entire automation app
Most API clients require writing custom Javascript wrappers and environment getters/setters just to pass an ID or token to the next request.
const response = pm.response.json();
pm.environment.set("token", response.token);
pm.test("Status is 200", function() {
pm.response.to.have.status(200);
});
This results in bloated test scripts, broken environment variable syncs, and tests that are impossible to review in Git.
Flexiberry uses the human-readable .berry syntax to describe requests, captures, and assertions out-of-the-box.
Step Call Api login
Capture
- token: response.token
Check
- $.status == 200
Zero dependencies, zero boilerplates. Variables are dynamically bound and passed down the execution chain automatically.
Interactive Demo
See Flexiberry in action
Key Features for
Sequential API Workflows
Flexiberry strips away the bloat and provides a lightning fast environment tailored for multi-API journeys.
Seamless Chaining
Extract headers, cookies, or body fields from one response and inject them into subsequent API requests natively.
Capture - token: response.token Header - Authorization: 'Bearer {{token}}'
Readable DSL Syntax
Write HTTP requests, variable declarations, and expectations in a structured, domain-specific script language.
Api POST #createUser Url "{{Config.baseUrl}}/users" Header - Content-Type: 'application/json'
Dual-Purpose Engine
Draft single scratchpad endpoints during development or run complex test runner flows with assertions.
# Execute tasks or single endpoint APIs
flexiberry run user.berry --api createUserCI/CD Automations
Lightweight, zero-dependency engine. Run your tests in local shells or trigger them in GitHub Actions workflows.
# GitHub Actions runner configuration - run: npx flexiberry run flow.berry
Environment Configs
Manage endpoints dynamically by swapping local dev, staging, or production env files without changing files.
Var @PROD Production Config - baseUrl: 'https://api.flexiberry.dev'
Who is Flexiberry For?
Backend Developers
A lightweight, CLI-first client to scratchpad daily endpoints and test stateful chains without leaving the terminal.
QA & Test Engineers
A git-friendly, text-based test suite that version controls cleanly, integrates natively in CI, and speeds up validations.
Product Teams
A transparent, human-readable way to model and verify core user integration stories (e.g. signup ➔ login ➔ profile).
Start building in minutes
Everything you need — from first steps to advanced Berry patterns.
Getting Started
Set up your first .berry project and run your first
test in under 5 minutes.
Core Concepts
Understand Api, Task, Step, and Check — the four
pillars of Berry.
CLI Reference
Every flag, option and exit code for flexiberry run documented with examples.
Ready to unlock
frictionless workflows?
Flexiberry is 100% open-source and community-driven. Take control of your API endpoints today.
npm install -g flexiberry Free forever · Open source · MIT License
