Crossposting

MDX Conversion Script

Converts a Wasp blog MDX file to clean markdown, HTML, and Medium-ready chunks. Output is saved to .claude/skills/crossposting/scripts/output/.

npx tsx .claude/skills/crossposting/scripts/convert-mdx.ts <path-to-mdx-file> [--publish-devto] [--update-devto <id>] [--upload-videos]

Output files (always written):

• <slug>.md — clean markdown (for DEV.to)
• <slug>.html — HTML (for Medium preview/reference)
• <slug>-medium-chunks.json — { title: string, chunks: string[] } pre-split at <h2> boundaries, pre-escaped for JS template literals

Flags:

• --publish-devto — POST as draft to DEV.to (requires DEVTO_API_KEY)
• --update-devto <id> — PUT to existing DEV.to article (requires DEVTO_API_KEY)
• --upload-videos — upload local .mp4s to YouTube (unlisted), embed as {% youtube URL %} liquid tags

Env vars: DEVTO_API_KEY (from https://dev.to/settings/extensions), YOUTUBE_CLIENT_ID + YOUTUBE_CLIENT_SECRET (saved in 1password for the users).

Notes:

• canonical_url is auto-generated from MDX filename → wasp.sh/blog/...
• Without --upload-videos, local .mp4 videos become plain links

YouTube Setup (one-time, human steps)

1. Create Google Cloud project → enable YouTube Data API v3 → create OAuth 2.0 Desktop credentials
2. Add YOUTUBE_CLIENT_ID and YOUTUBE_CLIENT_SECRET to ~/.zshrc
3. Run npx tsx .claude/skills/crossposting/scripts/upload-youtube.ts --auth → authorize in browser (select @wasplang channel if prompted)
4. Refresh token stored in ~/.youtube-upload-tokens.json
5. Check channel: npx tsx .claude/skills/crossposting/scripts/upload-youtube.ts --whoami. Wrong channel? Delete token file and re-auth.

Crossposting to Dev.to

Use --publish-devto or --update-devto <id> flags. Requires DEVTO_API_KEY.

Crossposting to Medium

Paste HTML into Medium's editor via Chrome DevTools MCP. The user must be logged in to Medium using email login (not google oauth) with info@wasp-lang.dev.

Steps

1. Convert the MDX article

Run the conversion script, if it hasn't been run yet (see usage above).

Images: Medium does not support webp. Convert webp images to jpg for later manual upload:

for f in static/img/<slug>/*.webp; do sips -s format jpeg "$f" --out ".claude/skills/crossposting/scripts/output/$(basename "${f%.webp}.jpg")"; done

2. Navigate to https://medium.com/new-story

The human user must login to Medium with the info@wasp-lang.dev email and get the OTP sent to your email.

3. Set the article title

Do NOT use the fill tool — it puts text into the body paragraph instead. Use evaluate_script with the setMediumTitle function from scripts/medium-helpers.js.

1. Read setMediumTitle from scripts/medium-helpers.js.
2. Replace TITLE_PLACEHOLDER with the actual title (escape backticks and ${ sequences).
3. Call evaluate_script with the resulting function string.

Then press Enter to move cursor to the body area.

4. Paste the article body

IMPORTANT: Do NOT use document.execCommand — it bypasses Medium's internal state and causes save errors. Always use synthetic ClipboardEvent paste.

IMPORTANT: Chunks are already pre-escaped for JS template literals and pre-processed for Medium (YouTube URLs, image placeholders). Inline each chunk string directly into the pasteMediumChunk function body where HTML_CHUNK_PLACEHOLDER appears. Do NOT base64-encode, store chunks in page variables, or add any intermediate encoding steps.

1. Read output/<slug>-medium-chunks.json — chunks are ready to paste as-is.
2. Click the body paragraph to focus it.
3. For each chunk, use evaluate_script with the pasteMediumChunk function from scripts/medium-helpers.js. Replace HTML_CHUNK_PLACEHOLDER directly with the chunk string content.
4. Wait for "Saved" status after all chunks are pasted.

5. Verify

• Snapshot the article to confirm it looks correct and shows "Draft" / "Saved"
• Scroll through to confirm section order matches the original and make any necessary adjustments.

6. Before Publishing (human steps)

• Replace [IMAGE: filename.jpg] markers with actual image uploads in Medium's editor
• Add any YouTube embeds that didn't auto-embed (Medium auto-embeds standalone YouTube URLs in <p> tags)
• Add the banner image and canonical URL
• Review and publish from Medium's UI