Workers - Control which routes invoke your Worker script for Single Page Applications

For those building Single Page Applications (SPAs) on Workers , you can now explicitly define which routes invoke your Worker script in Wrangler configuration. The run_worker_first config option has now been expanded to accept an array of route patterns, allowing you to more granularly specify when your Worker script runs. Configuration example: wrangler.jsonc { " name " : "my-spa-worker" , // Set this to today's date " compatibility_date " : "2026-07-03" , " main " : "./src/index.ts" , " assets " : { " directory " : "./dist/" , " not_found_handling " : "single-page-application" , " binding " : "ASSETS" , " run_worker_first " : [ "/api/*" , "!/api/docs/*" ] } } wrangler.toml name = "my-spa-worker" # Set this to today's date compatibility_date = "2026-07-03" main = "./src/index.ts" [ assets ] directory = "./dist/" not_found_handling = "single-page-application" binding = "ASSETS" run_worker_first = [ "/api/*" , "!/api/docs/*" ] This new routing control was done in partnership with our community and customers who provided great feedback on our public proposal . Thank you to everyone who brought forward use-cases and feedback on the design! Prerequisites To use advanced routing control with run_worker_first , you'll need: Wrangler v4.20.0 and above Cloudflare Vite plugin v1.7.0 and above