Vol. 03 · Field Guideswallowtail · redirect mappingupdated 2026 · 05 · 12
No. 01 · The Migration Problem

Every old URL
deserves a new home.

Upload two sitemaps. Get a clean redirect CSV. Stop losing rankings to 404s in the days after launch, when nobody's watching.

Map your redirectsno card · free up to 250 URLs
Apache · IIS · Nginx · JSON·v3.0.5 · 2026 · 05 · 12
PLATE I · fig. aold → new
/blog/2014/*old · indexed 2014/journal/$1new · 301apex · 0.94 confidence
No. 02 · The Product

A live extract from a 4,200-URL marketing migration. Wildcards collapsed eight ways.

A real run, mid-flight. Not a screenshot.

oldnewmatchconfidenceaction
/blog/2014/*612 urls/journal/$1pattern0.96accept
/services/consulting/work-with-us/consultingexact1.00accept
/products/widget-blue/shop/widget-blueexact1.00accept
/contact-us/contactfuzzy0.91accept
/our-team-page/about/teamfuzzy0.84review
/legacy-pricing3 candidateslow0.42manual
showing 6 of 4,217 rowsmedian time to CSV · 4m 12s
No. 03 · The Method

Three passes, fewer surprises.

i. exact

Same path? Done.

If /about exists on the old site and the new site, it gets accepted with no review. About 60% of a typical migration ends here.

ii. fuzzy

Close path? Scored.

If /our-team-page looks like /about/team, the matcher gives it a confidence score from 0 to 1. Anything under 0.75 goes to a review queue. It never lands in your CSV unless you accept it.

iii. wildcards

600 similar URLs? One rule.

When the matcher spots a pattern, like 600 dated blog posts under /blog/2014/*, it collapses them into one capture group that maps the whole tree at once.

The point is not to ship a 30,000-row spreadsheet. The point is to ship eighty-two regex lines and sleep through Monday morning.
from the swallowtail field notes, vol. 02

Two sitemaps in.
One redirect file out.

no credit card · free up to 250 URLs