Are there any battle-tested strategies for hiring that are generally known to be good, but aren't often used because it's hard or doesn't scale?

Asking because my business is growing and we've gotten lucky with our hires so far, but I'd like to add my discipline to hiring well.

Ask the best people you’ve ever worked with who the best people they’ve worked with are. Recurse. When names start repeating through different graph paths, make those people an offer they can’t refuse. Once they join, ask them to do the same, and give them the budget and role to make it happen.

Recommendation from a trusted 3rd party.

Bill Gurley has a great line about this:

"I use LinkedIn like this:

If Person A reaches out to me and there is a Person B that is a common connection between A and myself, I want to be able to call Person B and have 100% confidence in their evaluation. That's the bar I set to connect with someone on LinkedIn."

From:

https://www.youtube.com/watch?v=xmYekD6-PZ8

Apprenticeship? Actually spend time working with them on real work.

It's both hard and doesn't scale.

I think various ‘longer interview’ processes can be good by reducing the chance of particularly regretted hires. This could be internships (but note this goes two ways and you want interns to accept offers and recommend the programme to their friends even if they are not hired) or work sample tests. Both have the downside that they are more work for the candidate (especially internships or some other short-term-to-possibly-long-term position) and so experienced candidates who feel they have better options and less need to prove themselves typically won’t take part (this depends a bit on how much they want to work at your specific company of course). Potentially this isn’t so bad – competing to hire the same people as everyone else is going to be more expensive – or potentially it is bad – maybe there’s a reason those candidates are in high demand and you will suffer from only getting a look at people who didn’t fit the typical pattern. I think it’s going to depend a bunch on how good you are at sourcing candidates and how hot your firm is.

I do quick interviews, then hire hourly for a single scoped task. Then see how they play, communication skills, code exploring all that happens on the task. Only works when candidate is not otherwise engaged, has never worked for non-coding/sysadmin roles.

We source our intern-to-Junior pipeline from a good state school from which we have a few graduates. We have about an 80% placement rate for the interns. We’ve yet to have any abusive or bad hires, this being a fully remote company. For Senior hires, a prior employee founded a Java User Group and sourced several high quality engineers from the pool of visitors. So, build a pipeline and play the long game?

Previously we’ve sourced candidates via a reputable recruiter from an in-town firm that our manager can routinely sit down with and build a relationship over the years. This had a good rate with only one bad placement. We ultimately traded time cost for money cost in that one, but I liked it.

The worst outcomes we’ve had were via LinkedIn jobs posts. By the time our in-house full-time recruiter would give us resumes half would be obvious frauds with most of the remainder being subtle frauds. I blame this in good part to having non-technical staff as the first filter in our pipeline.

Unfortunately the firm makes money hand over fist year on year so we are no longer a lean mean operation but a burgeoning beauracracy with room to hide, rest, and vest.

Yes. Figure out who your top performers are ask them for referrals. Some people will recommend "meh" people, but more often than not your top performers hang out with other top performers because they appreciate the same things.