I added the /search page to my site with a form supporting multiple search engines. The hope is to give visitors a bit more choice in what companies to interact with.

The challenge was managing different query param for different sites.

• DuckDuckGo doesn't support multiple q= params, but does accept sites=
• Ecosia doesn't support a sites= param but does support multiple q= params (albeit with an extra comma requiring a space)
• Google does support a as_sitesearch= param but that was dropped with the addition of another q= param.

By adding several different hidden form fields, I was able to cover each engine (almost) seamlessly.
Then the only difference was the form action would could be defined on the button.
The final result is as follows:

<form rel="search" method="get">
    <input type="hidden" name="sites" value="ciccarello.me"/>
    <input type="hidden" name="q" value="site:ciccarello.me "/>
    <input type="text" name="q" placeholder="Search"/>
    <button type="submit" formaction="https://ecosia.com/search">Search with Ecosia</button>
    <button type="submit" formaction="https://www.google.com/search">Search with Google</button>
    <button type="submit" formaction="https://duckduckgo.com/">Search with DuckDuckGo</button>
</form>