Zally logo

Zally

Zally is an open source API linter from Zalando that validates OpenAPI 2 and 3 specifications against configurable rule sets for API design consistency. It exposes a REST API, command-line interface, and web UI for checking API designs against Zalando's RESTful API Guidelines or custom rule sets.

1 APIs 1 Capabilities 6 Features
API DesignAPI LintingAPI QualityOpen SourceOpenAPIZalando

APIs

Zally API

The Zally REST API performs linting of OpenAPI specifications against configurable rule sets. It returns violations grouped by rule severity (MUST, SHOULD, COULD, MAY, HINT), tr...

Capabilities

Zally Workflow

Unified workflow capability composing Zally APIs.

Run with Naftiko

Features

API Linting

Validate OpenAPI 2/3 specifications against rule sets to enforce design consistency.

Configurable Rules

Customize default Zalando RESTful API Guidelines rules or define custom rule sets.

Multiple Interfaces

REST API for programmatic access, CLI for local checking, and Web UI for visual review.

Ignore Extension

Use x-zally-ignore extension in specs to selectively bypass rules.

Rule Severity Levels

Rules categorized as MUST, SHOULD, COULD, MAY, and HINT for graduated enforcement.

Linting Statistics

Track linting requests and aggregate review statistics over time.

Use Cases

API Design Review

Review OpenAPI specs in pull requests to enforce design standards before merge.

API Governance

Enforce organizational API guidelines across teams via shared rule sets.

API Quality Gate

Block API releases that violate critical MUST rules in CI/CD pipelines.

Style Guide Enforcement

Encode an API style guide as executable rules and apply consistently.

Integrations

GitHub Actions

Run Zally linting in GitHub Actions workflows on PRs.

Spectral

Translate Zally rule sets to Spectral rulesets for OpenAPI 3 alignment.

Zalando RESTful API Guidelines

Default rule set ships with rules from Zalando's public API guidelines.

Semantic Vocabularies

Zally Context

10 classes · 29 properties

JSON-LD

API Governance Rules

Zally API Rules

18 rules · 5 errors 13 warnings

SPECTRAL

Resources

🔗
Website
Website
🔗
Documentation
Documentation
👥
GitHubRepository
GitHubRepository
👥
GitHubOrganization
GitHubOrganization
🔗
License
License
🔗
Issues
Issues
📄
ChangeLog
ChangeLog
🔗
CLI
CLI
📦
SDK
SDK
🔗
Specification
Specification
🔗
SpectralRules
SpectralRules
🔗
Vocabulary
Vocabulary
🔗
NaftikoCapability
NaftikoCapability

Sources

Raw ↑
aid: zally
name: Zally
description: >-
  Zally is an open source API linter from Zalando that validates OpenAPI 2 and 3
  specifications against configurable rule sets for API design consistency.
  It exposes a REST API, command-line interface, and web UI for checking API
  designs against Zalando's RESTful API Guidelines or custom rule sets.
type: Index
image: https://kinlane-productions.s3.amazonaws.com/apis-json/apis-json-logo.jpg
tags:
  - API Design
  - API Linting
  - API Quality
  - Open Source
  - OpenAPI
  - Zalando
url: >-
  https://raw.githubusercontent.com/api-evangelist/zally/refs/heads/main/apis.yml
created: '2026-03-25'
modified: '2026-05-03'
specificationVersion: '0.19'
apis:
  - aid: zally:zally-api
    name: Zally API
    description: >-
      The Zally REST API performs linting of OpenAPI specifications against
      configurable rule sets. It returns violations grouped by rule severity
      (MUST, SHOULD, COULD, MAY, HINT), tracks linting statistics, and lists
      supported rules. Authentication is via Bearer JWT.
    humanURL: https://opensource.zalando.com/zally/
    baseURL: https://zally.on.inter.net
    tags:
      - API Linting
      - API Quality
      - OpenAPI
    properties:
      - type: OpenAPI
        url: https://raw.githubusercontent.com/api-evangelist/zally/refs/heads/main/openapi/zally-api.yml
      - type: Documentation
        url: https://opensource.zalando.com/zally/
      - type: APIReference
        url: https://github.com/zalando/zally/blob/main/server/zally-server/src/main/resources/api/zally-api.yaml
      - type: Authentication
        url: https://github.com/zalando/zally/tree/main/server#authentication
      - type: JSONSchema
        url: https://raw.githubusercontent.com/api-evangelist/zally/refs/heads/main/json-schema/
      - type: JSONStructure
        url: https://raw.githubusercontent.com/api-evangelist/zally/refs/heads/main/json-structure/
      - type: JSON-LD
        url: https://raw.githubusercontent.com/api-evangelist/zally/refs/heads/main/json-ld/zally-context.jsonld
      - type: Example
        url: https://raw.githubusercontent.com/api-evangelist/zally/refs/heads/main/examples/
common:
  - type: Website
    url: https://opensource.zalando.com/zally/
    name: Zally Project Website
  - type: Documentation
    url: https://github.com/zalando/zally#readme
    name: Zally README
  - type: GitHubRepository
    url: https://github.com/zalando/zally
    name: Zalando Zally Repository
  - type: GitHubOrganization
    url: https://github.com/zalando
    name: Zalando GitHub Organization
  - type: License
    url: https://github.com/zalando/zally/blob/main/LICENSE
    name: MIT License
  - type: Issues
    url: https://github.com/zalando/zally/issues
    name: GitHub Issues
  - type: ChangeLog
    url: https://github.com/zalando/zally/releases
    name: Releases
  - type: CLI
    url: https://github.com/zalando/zally/tree/main/cli
    name: Zally CLI
  - type: SDK
    url: https://github.com/zalando/zally/tree/main/web-ui
    name: Zally Web UI
  - type: Specification
    url: https://opensource.zalando.com/restful-api-guidelines/
    name: Zalando RESTful API Guidelines
  - type: SpectralRules
    url: https://raw.githubusercontent.com/api-evangelist/zally/refs/heads/main/rules/zally-rules.yml
    name: Zally Spectral Ruleset
  - type: Vocabulary
    url: https://raw.githubusercontent.com/api-evangelist/zally/refs/heads/main/vocabulary/zally-vocabulary.yml
    name: Zally Vocabulary
  - type: NaftikoCapability
    url: https://raw.githubusercontent.com/api-evangelist/zally/refs/heads/main/capabilities/zally-workflow.yaml
    name: Zally Workflow Capability
  - data:
      - name: API Linting
        description: Validate OpenAPI 2/3 specifications against rule sets to enforce design consistency.
      - name: Configurable Rules
        description: Customize default Zalando RESTful API Guidelines rules or define custom rule sets.
      - name: Multiple Interfaces
        description: REST API for programmatic access, CLI for local checking, and Web UI for visual review.
      - name: Ignore Extension
        description: Use x-zally-ignore extension in specs to selectively bypass rules.
      - name: Rule Severity Levels
        description: Rules categorized as MUST, SHOULD, COULD, MAY, and HINT for graduated enforcement.
      - name: Linting Statistics
        description: Track linting requests and aggregate review statistics over time.
    name: Features
    type: Features
  - data:
      - name: API Design Review
        description: Review OpenAPI specs in pull requests to enforce design standards before merge.
      - name: API Governance
        description: Enforce organizational API guidelines across teams via shared rule sets.
      - name: API Quality Gate
        description: Block API releases that violate critical MUST rules in CI/CD pipelines.
      - name: Style Guide Enforcement
        description: Encode an API style guide as executable rules and apply consistently.
    name: UseCases
    type: UseCases
  - data:
      - name: GitHub Actions
        description: Run Zally linting in GitHub Actions workflows on PRs.
      - name: Spectral
        description: Translate Zally rule sets to Spectral rulesets for OpenAPI 3 alignment.
      - name: Zalando RESTful API Guidelines
        description: Default rule set ships with rules from Zalando's public API guidelines.
    name: Integrations
    type: Integrations
maintainers:
  - FN: Kin Lane
    email: [email protected]