1---
2name: expo-cicd-workflows
3description: Helps understand and write EAS workflow YAML files for Expo projects. Use this skill when the user asks about CI/CD or workflows in an Expo or EAS context, mentions .eas/workflows/, or wants help with EAS build pipelines or deployment automation.
4allowed-tools: "Read,Write,Bash(node:*)"
5version: 1.0.0
6license: MIT License
7---
8 
9# EAS Workflows Skill
10 
11Help developers write and edit EAS CI/CD workflow YAML files.
12 
13## Reference Documentation
14 
15Fetch these resources before generating or validating workflow files. Use the fetch script (implemented using Node.js) in this skill's `scripts/` directory; it caches responses using ETags for efficiency:
16 
17```bash
18# Fetch resources
19node {baseDir}/scripts/fetch.js <url>
20```
21 
221. **JSON Schema** — https://api.expo.dev/v2/workflows/schema
23   - It is NECESSARY to fetch this schema
24   - Source of truth for validation
25   - All job types and their required/optional parameters
26   - Trigger types and configurations
27   - Runner types, VM images, and all enums
28 
292. **Syntax Documentation** — https://raw.githubusercontent.com/expo/expo/refs/heads/main/docs/pages/eas/workflows/syntax.mdx
30   - Overview of workflow YAML syntax
31   - Examples and English explanations
32   - Expression syntax and contexts
33 
343. **Pre-packaged Jobs** — https://raw.githubusercontent.com/expo/expo/refs/heads/main/docs/pages/eas/workflows/pre-packaged-jobs.mdx
35   - Documentation for supported pre-packaged job types
36   - Job-specific parameters and outputs
37 
38Do not rely on memorized values; these resources evolve as new features are added.
39 
40## Workflow File Location
41 
42Workflows live in `.eas/workflows/*.yml` (or `.yaml`).
43 
44## Top-Level Structure
45 
46A workflow file has these top-level keys:
47 
48- `name` — Display name for the workflow
49- `on` — Triggers that start the workflow (at least one required)
50- `jobs` — Job definitions (required)
51- `defaults` — Shared defaults for all jobs
52- `concurrency` — Control parallel workflow runs
53 
54Consult the schema for the full specification of each section.
55 
56## Expressions
57 
58Use `${{ }}` syntax for dynamic values. The schema defines available contexts:
59 
60- `github.*` — GitHub repository and event information
61- `inputs.*` — Values from `workflow_dispatch` inputs
62- `needs.*` — Outputs and status from dependent jobs
63- `jobs.*` — Job outputs (alternative syntax)
64- `steps.*` — Step outputs within custom jobs
65- `workflow.*` — Workflow metadata
66 
67## Generating Workflows
68 
69When generating or editing workflows:
70 
711. Fetch the schema to get current job types, parameters, and allowed values
722. Validate that required fields are present for each job type
733. Verify job references in `needs` and `after` exist in the workflow
744. Check that expressions reference valid contexts and outputs
755. Ensure `if` conditions respect the schema's length constraints
76 
77## Validation
78 
79After generating or editing a workflow file, validate it against the schema:
80 
81```sh
82# Install dependencies if missing
83[ -d "{baseDir}/scripts/node_modules" ] || npm install --prefix {baseDir}/scripts
84 
85node {baseDir}/scripts/validate.js <workflow.yml> [workflow2.yml ...]
86```
87 
88The validator fetches the latest schema and checks the YAML structure. Fix any reported errors before considering the workflow complete.
89 
90## Answering Questions
91 
92When users ask about available options (job types, triggers, runner types, etc.), fetch the schema and derive the answer from it rather than relying on potentially outdated information.
93