Solving Duplicate URL Slugs for Repeated Talks: A Future-Proof Approach

I rarely repeat talks, but while talking to other speakers I realized I might be the only one doing that, though my sample size is small. While reviewing my site I noticed something strange: one of my very first talks that I gave at Agile Testing Days 2020 opened a different event page. It turned out my slug logic used only the title, so repeating a talk created duplicate URLs. I have three repeated talks over the last five years, enough to show this is not just an edge case but something that needed a scalable fix for SEO and usability.

Here is how I fixed multiple talks with the exact same title produced identical slugs and thus conflicting URLs in a future-proof way that is also SEO-friendly.

The Problem

I rarely give the same talk with the same title. Since my slug logic generated URLs based on the title, this happened:

Speeding up your test execution in a fast-paced world (2021-02-23, Online) > /talks/speeding-up-your-test-execution-in-a-fast-paced-world
Same talk, different event/date (2020-11-10, Agile Testing Days) > same slug!

This caused:

Clashing pages
SEO confusion
Confused user

Classic approaches, like appending the year or city, fail if you repeat talks more than once in a year or at the same place. Adding the conference or event name would solve this on a first thought but it is still possible that the event is the same (e.g. "Online", "Webinar"). Another reason against this is that the URLs would get even longer which I want to avoid.

The Requirements

No breakage of existing or "canonical" links (SEO + old bookmarks).
For every future duplicate: URLs must always be unique and stable.
Zero manual maintenance. No hand-editing slugs or special cases.

The Solution: Unique Slugs via ID Suffix

Rather than rely on talk metadata that might itself collide, I leveraged a data property I know is always unique: the database (array) id field.

First occurrence: Keeps the original pretty slug (great for established links and nice URLs).
Subsequent duplicates: Get the slug plus ID: e.g., /talks/speeding-up-your-test-execution-in-a-fast-paced-world-10

With this approach, even if I give a talk with the same title 30 times, each will have a unique, never-colliding, discoverable URL.

Code (simplified):

function getUniqueTalkSlug(talk, allTalks) {
    const baseSlug = slugify(talk.title);
    let seen = 0;
    for (const t of allTalks) {
        if (slugify(t.title) === baseSlug) {
            seen++;
            if (t.id === talk.id) {
                return seen === 1 ? baseSlug : `${baseSlug}-${talk.id}`;
            }
        }
    }
}

How This Changed My Workflow (and Could Change Yours)

I never have to manually check for collisions.
When I add another instance of the same talk, its slug is always unique by design.
Legacy links stay valid.
Only the “first” talk with any title gets the plain slug.
SEO is happy, and so are people!
Every talk page is independently addressable, discoverable, and readable.

Lessons Learned

Automate uniqueness early: It’s worth a tiny bit of index logic.
Plan for duplicates: Never assume titles or metadata are unique.
Preserve legacy links: SEO and users depend on it.

Real-World Impact

After deploying this update my talks page:

No longer has conflicting URLs.
Is fully future-proof, with zero extra maintenance for the next talks.
Is better indexed and more reliable for humans and robots alike.

If you run any site where titles could repeat: conference talks, events, blog posts, whatever, consider this approach!