In this industry when you hire entry-level people and train them you know the risks. The alternative is to hire more-expensive professionals, who you still have to train. You've been there 3 years, and so you're just entering the 3-5 year window when you should be making the next big step in your career, whether it's in your current company or another one.

Does that gratitude (for training) need to impact how long I stay at this company?

No. Training is a normal, ongoing part of any (good) job in software. If you had to stay a year after you learned anything new, you could never leave.

A factual assumption in the question

IS WRONG.

OP writes:

"they've been investing in me tremendously by..."

that statement

IS INCORRECT.

The company has been paying a pittance on side benefits such as gym membership, the very cheap training mentioned, and free donuts, specifically to trick gullible young employees in to working hard for them for low money.

In this situation employees are literally being tricked in to an "I am obligated to the company" mentality for an unnecessarily low salary.

This is an explicit, widely-known, feature of Silicon Valley culture and software culture broadly today.

Founders and financial-level management in companies literally sit down and explicitly discuss and plan what sort of nonsense like ping ping tables and "certifications" they can spend a tiny amount of money on, to trick folks in to working for a low salary.

This is the norm in almost all software companies or companies with a software function.

It is a standard, explicit, feature of the industry today.

In Silicon Valley there are literally consultants who analyze this donuts-and-certificates nonsense to decide what is the best "pennies on ping pong, rather than tens of millions in salaries" for maximum effect.

You can literally see new ideas in this field being tried from year to year:

"Flexible! vacation time! you decide!" is a recent idea a consultant came up with, and you see it now frequently. "A budget! to buy your own gear!" ... "home valet service!" ... "work on open source Thursdays!"

Etc, etc, etc.

In a few years when OP is leading a team, OP will literally be talking with the Founders and accounting side about how to keep Young Timmy and Jenny on the team - without, of course, jacking up their salary. Will Timmy will respond better to a $200 "certification", casual! Fridays, a slice of pizza, a trip! to London, or a new! clicky gaming keyboard ... instead of jacking up Timmy's salary 40k.

Because programming is so expensive, it's become standard "Silicon Valley culture" to have idiocy like "free lunch" and (literally!) ping pong tables, in an effort to keep contract prices down.

The actual statements of OP such as:

"I feel very grateful..."

.. literally make me feel sad, because someone is being CONNED.

Software is often an incredibly high value-generating function.

It's nothing for a programmer to generate a hundred times the value they are paid in a year.

If feeling grateful, I would urge to rethink that, as one's entire future depends on it.

To simply answer the two questions:

"would it burn bridges to leave...

Of course not.

30 seconds after you are gone nobody will know or remember your name.

Regarding their comic spending on donuts, ping pong tables, $200 training courses, and Friday Pizza, it means nothing. Nothing.

Founders sit down explicitly and discuss what such idiocy they can spend a few pennies on to avoid paying money to programmers.

If thinking about how it will look "on your resume" in 10 years:

1. Once your career is underway, programmers typically don't even type in that "first job" since it was so lowly paid. You'll likely never even mention it again.

2. "First job syndrome" is a serious problem. Any programmer who took forever - years - to move along from their first job, you wonder why. Did they not get offers? Were they comfortable in a rut working for low pay?

"would it be "disloyal" to leave...

This concept is not a thing.

If the company was losing one dollar a week on someone, they'd be instantly let go by the corporate machine of accounting and money, as a mechanical action, an arithmetical decision with no human involvement whatsoever.

(Far less "loyalty" ... what? from whom? how? There is not even a mechanism for such a thing.)

If the company happened to go bankrupt, you'd get a form letter from some liquidators stating what date you were terminated and how much money you have lost.

If a new team lead comes on with her own crew you will be let go without your name even being mentioned.

The notion "business is business" really doesn't cover the situation strongly enough.

--

If one is looking for negotiation language, it's very simple because you have ALL the power.

Steve, as you know I've passed that "first job" stage. I am now regularly offered { insert figure, say $40,000 } more than I'm currently getting. What to do?

Negotiation is trivial when you have ALL the power.

Just follow the basics: be polite, ask questions. If they don't send over what you want

Understood, is Friday ok for the company as a last day?

Another important point...

"... these new tools bumps my salary potential up by at least 50% increase. ..

OP is stating that the "training" given has bumped OP's earning potential by 50%.

This is wholly wrong.

1. 100% of talented programmers, make a low wage the first year or so, then their wage skyrockets. It is an absolutely standard feature of the business. Any specific hokey certifications or specific "training" is wholly unrelated.

2. Every programmer, every month of their career from start to retirement is constantly aggressively learning totally novel technology. The everyday nature of programming is research-level learning. This is an obvious given of "being a programmer". Languages, platforms, paradigms change constantly. If the company in question did or didn't offer a few dollars in "certificates" or "training" ... makes no difference whatsoever to the fact that the OP (like every programmer) is constantly "worn out on learning" as a matter of course.

The grass is not necessarily greener on the other side.

You value a higher salary, that's fine. What happens 5 years after that? Is this new company going to invest in you or will they simply fire you and offer a new guy the higher salary?

Companies that invest in their employees are getting rarer. It is unlikely your new manager have the same level of interest in your career development as your current manager; the new manager most certainly didn't train up internally, since they just scooped a freshly trained guy somewhere else!

You have to spend time thinking about the benefits your current employer is providing, not just the salary. Discontentment with a job is rarely solved by a salary bump, so a job "improvement" is also not just a salary bump.

A picture saves a thousand words.

(source: dilbert.com)

Loyalty and commitment will give you the opportunity to gain experience in a happy stable environment. It's not all about the money. With experience, you can be better prepared for times when the milk turns sour. If you enjoy working there and you are doing what makes you happy, then slog it out and enjoy the good times until redundancy or boredom.

While it is okay to leave (barring any clauses in your contract) I would urge caution in this.

Your company just invested a small fortune on you. Companies don't throw money at things, they make investments. They see something in you that said "let us spend money that we don't need to spend on making this person more valuable".

Since you were singled out among a few, it may be that they are looking to promote you.

If you like the company and the people, I would recommend waiting it out at least another year and see where this goes. If nothing changes, you can always move on then, in the mean time, in addition to those certificates and trainings, you can put them to real, practical use.

Then, see about getting a salary bump or promotion in your current company.

There are so many bad companies out there that when you find a good one, you should give them a bit of leeway. The grass may always be greener on the other side of the fence, but remember, it's still grass.

You are established at your company, and it looks like they think you are ready for a leadership role. If money is your principle reason for moving on, don't do it. You an always make money, but making a enough money at a job in a company you love is far better than making a fortune at a job where you curse your very existence (been there)

Talk to your manager/supervisor and ask about advancement at your current company. Tell them that you are excited about all the training you have received, and that you'd like to put it to use.

See what they can do for you.

I know there are some industries where there are only 2 companies, and it is normal that people switch between them several times in their career, as that is the way to advance.

Some employees see any quitting at all as disloyal.

Most realize that business is business, and leaving is part of the job. If you didnt enter any agreements for your training, you are free to go. These agreements could be contractual (trainee pilots have to serve x years or pay Y amount of money after training is finished and they are real pilots.) Or it could be an explicit gentlemens agreement, like I train you in X and you stay Y years here (my Uncle did that once).

That having said, if you like it there, you might want to have an open discussion with your boss. This is if you trust him to do so. State you would like to stay and earn X amount of money at your company. This is the polite way of telling: I want to earn this money, here is cool, but I am willing to go if I have to. Obviously, acceptable phrasing can depend on culture and phrasing. Think about how much you would accept. would be 30% cool? 40%? Of course, you might get a bit more somewhere else, but you know that you have a boss here who trusts you and invests in you. So you have to weigh how much that is worth to you.

Firstly, check your contract. It is possible that it covers what happens with training. For me, my contract says that if I leave within a year of getting training, I have to pay back 1/12th of the cost of that training per month remaining to hit a year. (That is, if I get £600 worth of training and leave 9 months later, I have to pay the company £150).

Beyond the legalities, your career and your life should normally be your highest priority. If you can truly get a 50% higher salary elsewhere, and bearing in mind that pay rises tend to accumulate over time, you could be giving up on tens or even hundreds of thousands of currency units over the course of your life, just to show loyalty to a company that sent you on a training course. Many would consider that an unrealistically steep price to pay.

On the flip side, not every company is willing to invest in their staff's future. You've had this training, and you say the new manager is good, and wants to take the company, the team, and the staff in a good direction. You might not get that elsewhere. Depending on the nature of the work and the people and your career goals, those might be reasons to stay. Perhaps you might be able to ask for a pay rise instead of leaving. Something to think about.

In either case: it is your choice. If you decide to leave, you are free to do so - workers change companies all the time, for all kinds of reasons. If receiving training obligated you to stay at a company that you say is underpaying you by 50%, unscrupulous companies would just drip out cheap training courses a couple of times a year so they can demand no-one ever leaves, while also refusing to pay people properly. That's not how employment works. You are free to move on if you wish.

Does that gratitude need to impact how long I stay at this company? I know business is business, but would it be "disloyal" or burn bridges to leave within a year after getting that training?

Being grateful and expressing that gratitude is important.

At the end of the day, their primary motivation for investing in you is because it benefits the company. If it didn't then they wouldn't do it. Very often our emotional self gets involved in our work life... because we're human beings. But this is not a personal relationship. This is a business relationship. You owe them no loyalty or fealty. They'll do what's best for the business. You need to be in the business of "you" and do what's best for your career. If you choose to leave, express your gratitude for the training and the opportunity and leave it at that.

The company would have no feelings of guilt, or betrayal, or disloyalty if they were letting you go, because it's business... not personal.

Does that gratitude need to impact how long I stay at this company? I know business is business, but would it be "disloyal" or burn bridges to leave within a year after getting that training?

The growth and training that the company has been giving you is so that you can be a better employee for the company. Yes you should be grateful, but at the same time you need to understand that they are not doing this just for you. It is never disloyal to leave a company if you have a better opportunity elsewhere. If you are truly valued at 50% more than what you currently make, you should take that opportunity wherever it may come.