I see this may be a duplicate, however, my sense is that it’s important to discuss the degree to which you should reference the job posting you mentioned. Onwards:
You are owed compensation that is fair and commensurate with the value you bring.
It sounds like a lot has changed since you were hired: you’ve grown a lot, developed a diversity of expertise, devised and executed new projects, and generally contributed both in significant and meaningful ways. Importantly, you’ve taken on responsibilities outside of your original role. I think it’s worth sharing a backstory here so you can weight this answer appropriately:
I once found myself in a similar position. I was a junior developer at an agency and was assigned a lead developer role on a flagship project. The project was tough, and I can’t honestly say it came out exactly as I’d hoped - due to a number of constraints and factors that weren’t in my (or the agency’s) control. However, upon completion I sat down with my manager and presented him with a few assertions:
I was grateful for the opportunity to lead the project and we agreed it had turned out well given the challenges that presented.
I asserted that in giving me, a junior developer, a flagship project the company had demonstrated their confidence in my ability to execute in a lead position (i.e. you generally don’t give junior devs high stakes projects).
I noted that I enjoyed working at the company and felt that I had a lot more to contribute to future projects.
I then went on to say that, on a personal level, I felt confident in my abilities and that I had grown much since I originally took on the junior dev role. But then I went further and stated that I felt confident enough in my abilities that I could readily explore the job market and receive an offer with significantly more compensation (this was certainly true, but it was nonetheless a risky thing to say to a boss).
I then emphasized that this conversation was not about money, it was about feeling valued in my role, having my effort and execution recognized, and my compensation reflect the value I was bringing to the company.
I wrapped up by saying I felt I should be promoted — this was a possibility that had been discussed prior to the project in a semi-annual review. Within a few weeks, this came to pass.
You will be promoted less frequently and receive fewer pay raises if you don’t ask.
The long term solution to this challenge is to work with your boss or relevant management to create a personal development plan. Discuss what your goals are, how you want to grow, what level of responsibility you would like to take on, and what you can do best to help the organization succeed in its mission.
This plan should include regular milestones (say every 6 months or year) around the skills you and the company would like to see you develop, your competencies, and your goals. If you have no formal performance review process in place, try to set one up with your director or manager. By doing this, both you and your company will be able to gauge your performance and growth against the measures you have defined together. Assuming your success, you’ll have powerful evidence and preset agreements for regular pay raises and promotions.
Now, in terms of your immediate situation, you could do this: Have a polite, friendly, non-adversarial conversation with your manager about the potential for a pay raise or a promotion (often the surest way to get a good raise). Frame it in terms of the value you bring and your desire to feel that the work you do is valued appropriately. Your prior raises mandated by the government don’t count; only merit based raises are relevant to the conversation.
Initially, you probably don’t want to reference the job posting directly. While the job posting may help indicate your value and the extent of the raise you can shoot for, the conversation is entirely about your performance, contributions, and what you feel would be fair compensation for you. That said, it does often help to provide a number that is objectively reasonable. To do this, you can gauge your fair market rate using resources like Glassdoor. Once they present you with an offer, if it is below what the job posting advertised you can bring it up then.
Further, from the question, it sounded like you’re paid hourly. Another way to boost your compensation indirectly may be to propose switching to a salaried compensation structure. This may lower your tax burden and open you up to other benefits like PTO, health, dental, and/or vision insurance, paid sick leave, paid maternity or paternity leave, and a tax deferred retirement savings account that your employer contributes to. Generally speaking, all company benefits are considered part of your compensation package and are negotiable.
After having the discussion and securing a raise or promotion you’re satisfied with, leverage the conversation you just had into one about developing a personal development plan with your manager. Avoid having this personal development plan conversation first — you want to get a raise first, otherwise you may push your raise back 6 months to a year!