Building Your Dream Career: Part 4 - The First 90 Days

Nov 5

Setting Yourself Up to Extract Maximum Value

You did it. You navigated the brutal job market, stood out among hundreds of qualified candidates, and landed an offer. You negotiated (or wish you had), signed the paperwork, and now you're staring at your calendar counting down to Day One.

And suddenly, a new kind of anxiety sets in: What if I can't actually do this job?

I've started enough new roles—from IBM internships to Boeing to my current startup—to know that the first 90 days aren't just about proving you can do the job. They're about setting up the entire trajectory of your time at that company.

Get the first 90 days right, and you create momentum that carries you forward for years. Get them wrong, and you spend the rest of your tenure trying to overcome that initial impression and catch up to where you should be.

This is Part 4 in my series on building your dream career. We've covered understanding yourself, finding the right opportunities, and standing out in the application process. Now comes the part nobody really prepares you for: those crucial first three months that determine whether this job becomes a stepping stone toward your goals or just another line on your resume.

The Real Purpose of Your First 90 Days

Let's start by reframing what the first 90 days are actually about.

Most people think the goal is to "prove yourself" or "show you can do the job." That's not wrong, but it's incomplete. The real goals of your first 90 days are:

Build credibility and trust so people actually want to work with you
Understand the landscape so you can navigate effectively
Identify opportunities to add value beyond your job description
Establish patterns that will serve you for your entire tenure
Set yourself up to extract maximum value from this experience

Notice what's not on that list: becoming an expert, knowing everything, or single-handedly solving major problems.

Your first 90 days aren't about being the smartest person in the room. They're about being the person who asks good questions, learns quickly, and makes people feel good about hiring you.

Week 1-2: Observe, Absorb, and Build Relationships

Your first two weeks should be 80% learning and 20% doing.

I know the temptation to immediately start contributing—you want to prove you deserve to be there. Resist it. The people who try to make big impacts in their first week usually create more work for everyone else because they don't understand the context yet.

What to Actually Do in Week 1-2

Map the social landscape

Who makes decisions and who has influence (not always the same people)
Who knows the most about different parts of the system
Who's willing to help new people vs. who to approach carefully
What the actual working relationships are like (ignore the org chart)

Understand the technical landscape

How does the codebase/system actually work (not what the documentation says)
What's the tech debt everyone's living with
What are the pain points developers complain about
Where are the "here be dragons" parts of the system nobody wants to touch

Learn the cultural norms

What time do people actually start working (not what's officially required)
How do people communicate (Slack culture, email culture, meeting culture)
What's the attitude toward work-life balance in practice
How are decisions really made vs. how they're supposed to be made

Build relationships deliberately

Set up coffee chats or virtual meet-and-greets with:

Your immediate team members
People whose code you'll be working with
People in adjacent teams you'll interact with
That one person everyone says is incredibly helpful

In these conversations, ask about their work, what they're excited about, what challenges they're facing. Listen more than you talk. Take notes.

When I started at Boeing, I spent my first week having coffee chats with everyone on my team and several people from related teams. I learned more in those conversations than I did from any official onboarding documentation. I found out about undocumented processes, learned who to ask for what, and started building relationships that would serve me throughout my entire time there.

What Not to Do in Week 1-2

Don't immediately propose big changes You don't understand why things are the way they are yet. That "obviously broken" process might be working around a constraint you don't know about.

Don't hide your confusion Ask questions. Lots of them. People expect you to be confused in week one. They'll be suspicious if you act like you understand everything.

Don't skip the boring onboarding stuff Yes, watching those compliance videos is painful. Do it anyway. Understanding official processes and policies gives you the context for when you can bend rules and when you absolutely can't.

Don't try to prove you're the smartest person in the room Nobody likes the new person who shows up acting like they have all the answers. Even if you do know better ways to do things, earn the right to be heard first.

Week 3-4: Start Contributing (Strategically)

By week three, you should start actively contributing, but be strategic about what you take on.

The "Quick Win" Strategy

Look for opportunities that are:

Valuable enough to matter but not so critical that failure would be catastrophic
Well-defined so you can succeed without months of context
Visible so people notice your contribution
Different from what you'll do long-term so you're not pigeonholed

When I joined my current startup, one of my first contributions was fixing a nagging bug that had been on the backlog for months. It wasn't glamorous, but it was annoying enough that fixing it made people notice me positively. It showed I could work with the codebase, it made life better for the team, and it built credibility without requiring deep domain expertise.

What Makes a Good First Project

Good first projects:

Solve real problems, even small ones
Have clear success criteria
Let you learn the codebase/system while contributing
Give you natural reasons to interact with different people
Can be completed in 2-4 weeks

Bad first projects:

Require deep institutional knowledge to navigate
Have unclear requirements or constantly shifting goals
Are in parts of the system nobody understands
Depend on other people's work you can't control
Have been "in progress" for months with multiple people failing

If your manager assigns you something that smells like a bad first project, push back gently: "I'm excited to work on this, but I want to make sure I have the context I need to be successful. Can we start with something smaller so I can build up to this?"

Start Documenting Everything

Here's something that will pay dividends throughout your entire tenure: start documenting as you learn.

Every time you:

Figure out something that wasn't documented
Learn a non-obvious process
Discover why something works the way it does
Get helpful advice from someone

...write it down. Not just for yourself—for the next person.

At Boeing, I started documenting everything during my onboarding because I was frustrated by how much wasn't written down. Those notes eventually became the official onboarding documentation that reduced ramp-up time by 40% for the next cohort. That documentation became one of my strongest accomplishments when I was advocating for promotion.

Writing documentation in your first 90 days serves multiple purposes:

Cements your own understanding
Provides value that people notice
Identifies gaps in organizational knowledge
Establishes you as someone who improves things
Creates artifacts you can point to later

Week 5-8: Expand Your Impact (Carefully)

By week five or six, you should have a sense of the landscape and some credibility from initial contributions. Now you can start expanding your impact—but carefully.

Finding Opportunities Beyond Your Job Description

This is where you start turning a job into a stepping stone.

Look for opportunities that:

Align with your long-term goals (remember Part 1 - your priorities)
Fill gaps the team has but nobody's addressing
Let you build skills you want to develop while solving real problems
Create visibility with people who matter for your career trajectory

When I joined Boeing's software engineering team, my job description didn't include machine learning. But I noticed the team was starting to explore ML applications and didn't have deep expertise. I raised my hand, took on some initial ML work, and eventually positioned myself to join their ML initiatives. That experience helped me realize how much I loved AI/ML work and directly influenced my decision to pursue my master's degree in that field.

The "Stretch Assignment" Conversation

Around week 6-8, have this conversation with your manager:

"I'm feeling good about [initial responsibilities]. I'd like to start taking on some additional challenges. Are there any projects or areas where the team needs help that would also help me develop [skill you want to build]?"

This conversation does several things:

Shows initiative and growth mindset
Signals you're not just doing the minimum
Lets you guide your own development
Gives your manager an opportunity to advocate for giving you interesting work

Building Your Internal Network

By week 6-8, you should be expanding beyond your immediate team.

Attend optional events and meetings

Team demos and showcases
Brown bag lunch sessions
Cross-functional planning meetings
Social events (even if you hate them)

Volunteer for cross-team initiatives

Working groups on technical standards
Diversity and inclusion committees
Hackathons or innovation challenges
Onboarding buddy programs

These activities serve multiple purposes:

You meet people across the organization
You learn how different parts of the company work
You build relationships that can help you later
You demonstrate engagement beyond just your role

When Boeing asked for volunteers to represent engineering at Women Who Code's virtual conference, I raised my hand even though I was relatively junior. That visibility led to recognition from leadership several levels above me and positioned me as someone willing to represent the company externally.

Week 9-12: Establish Your Long-Term Patterns

By the end of your first 90 days, you should be establishing the patterns that will define your entire tenure.

Setting Sustainable Expectations

Here's a trap many people fall into: they work unsustainable hours in their first 90 days to prove themselves, then burn out or create expectations they can't maintain.

If you work 60-hour weeks for your first three months, people will expect 60-hour weeks forever. When you pull back to sustainable hours, it looks like you're slacking off.

Instead, establish the working pattern you can actually sustain:

If you value work-life balance, demonstrate that from the start
If you need flexible hours for family obligations, establish that pattern early
If you're most productive in certain hours, communicate that

I learned this the hard way at Boeing. I took on too much too fast—managing four interns, taking on additional projects, volunteering for everything—and ended up overwhelmed. It took months to reset expectations and establish more sustainable patterns.

The 90-Day Check-In

Around day 90, request a formal check-in with your manager. Come prepared with:

What you've accomplished:

Projects completed
Problems solved
Relationships built
Things you've learned

What you're planning next:

Areas you want to develop
Projects you're interested in
Skills you want to build
How you want to grow

What you need:

Resources or support
Clarity on expectations
Feedback on performance
Guidance on priorities

This conversation establishes a pattern of proactive career management and ensures you and your manager are aligned on your trajectory.

The Skills That Matter Most in Your First 90 Days

Let's talk about what actually matters when you're ramping up in a new role.

Technical Skills Are Table Stakes

Yes, you need to be technically competent. But being the best coder on the team won't matter if you can't work effectively with others or understand the broader context.

The Skills That Actually Differentiate You

Asking good questions

Questions that show you're thinking deeply
Questions that help you understand context, not just facts
Questions that demonstrate genuine curiosity

Communicating clearly

Explaining what you're working on and why
Flagging blockers before they become crises
Updating people proactively
Writing clear documentation and messages

Managing your manager

Understanding their priorities and pressures
Making their job easier, not harder
Communicating in ways they prefer
Knowing when you need their input vs. when you can decide

Reading the room

Understanding unspoken dynamics
Knowing when to push and when to let something go
Recognizing what's politically sensitive
Navigating organizational culture effectively

Being pleasant to work with

Responding to messages in reasonable time
Following through on commitments
Being helpful when people ask
Not creating drama or negativity

These "soft skills" matter far more than your technical abilities in determining whether people want to work with you—and people wanting to work with you is what creates opportunities.

Common First 90 Days Mistakes (And How to Avoid Them)

Let me share mistakes I've made or watched others make:

Mistake #1: Trying to Prove You're Worth the Salary

Nobody's actually tracking whether you've justified your salary in your first three months. They expect you to be net-negative in terms of immediate output while you ramp up.

Instead of proving your worth through output, prove it through learning speed, cultural fit, and building relationships.

Mistake #2: Not Asking Enough Questions

People expect you to be confused and ask questions in your first 90 days. They start getting concerned if you ask questions six months in.

Ask everything now. Better to feel slightly annoying than to make preventable mistakes because you were afraid to ask.

Mistake #3: Committing to Everything

When you're new, people will ask if you want to take on various projects or join different initiatives. The temptation is to say yes to everything to prove you're eager.

Don't. Be selective. Say yes to things that align with your goals and where you can actually deliver. Say no (politely) to things that don't serve your development.

Mistake #4: Ignoring the Political Landscape

Every organization has politics. Pretending they don't exist won't make them go away—it'll just make you blind to important dynamics.

Pay attention to:

Who has influence and why
What topics are sensitive
What initiatives have support vs. which are likely to fail
Who's respected and who's just tolerated

You don't have to play politics actively, but you need to understand the landscape.

Mistake #5: Not Building Relationships Outside Your Team

Your immediate team is important, but opportunities often come from people outside your team who know your work and can advocate for you.

Invest time in meeting people across the organization, even when there's no immediate benefit.

Mistake #6: Accepting Everything at Face Value

When people tell you "this is how we do things," that might mean:

This is actually how we do things
This is how we're supposed to do things but nobody does
This is how we used to do things
This is how one person does things

Learn the difference between actual practice, official policy, and individual preference.

The Mindset That Makes the First 90 Days Work

Here's the mental framework that helped me navigate multiple onboarding experiences:

You're not here to know everything—you're here to learn quickly

Give yourself permission to be confused, to ask stupid questions, to not understand things. The goal isn't to fake expertise you don't have. It's to demonstrate that you can acquire the expertise you need.

You're building relationships, not just completing tasks

Every interaction is an opportunity to show people that you're:

Thoughtful
Easy to work with
Genuinely interested in the work
Someone they want on their team

Tasks come and go. Relationships compound.

You're setting up your entire tenure, not just passing probation

The patterns you establish in your first 90 days are hard to change later. Set sustainable expectations, build the reputation you want, and position yourself for the opportunities you actually want.

This job is a stepping stone (even if it's a great one)

Remember your long-term goals from Part 1. Even if this is a job you love, use the first 90 days to position yourself to extract maximum value—skills, experience, relationships, and opportunities that serve your career trajectory.

The First 90 Days Checklist

Here's a practical checklist for what you should accomplish in your first three months:

Week 1-2:

[ ] Meet with everyone on your immediate team
[ ] Meet with key stakeholders in adjacent teams
[ ] Understand the technical landscape and major systems
[ ] Learn the communication and cultural norms
[ ] Complete all official onboarding requirements
[ ] Ask approximately 10,000 questions

Week 3-4:

[ ] Complete your first meaningful contribution
[ ] Start documenting things you've learned
[ ] Establish your working patterns and hours
[ ] Identify gaps or opportunities you might address
[ ] Build relationships beyond your immediate team

Week 5-8:

[ ] Take on a stretch assignment aligned with your goals
[ ] Volunteer for something visible but low-risk
[ ] Continue building your internal network
[ ] Start having career development conversations with your manager
[ ] Identify 2-3 areas where you want to develop expertise

Week 9-12:

[ ] Request a 90-day check-in with your manager
[ ] Assess whether this role is serving your long-term goals
[ ] Establish sustainable working patterns
[ ] Document your accomplishments
[ ] Plan your next 90 days

What Success Actually Looks Like at Day 90

Let's be specific about what "success" means at the end of your first 90 days.

You should be able to answer "yes" to most of these:

Technical competence:

Can you contribute productively to your team's work?
Have you completed projects that added value?
Do people trust you with meaningful tasks?

Organizational understanding:

Do you understand how decisions get made?
Do you know who to ask for what?
Can you navigate the political landscape?

Relationship building:

Have you built positive relationships with your team?
Do people outside your immediate team know who you are?
Would people choose to work with you on projects?

Strategic positioning:

Have you identified opportunities aligned with your goals?
Have you started building toward your long-term objectives?
Are you set up to extract maximum value from this experience?

Sustainable patterns:

Are you working at a pace you can maintain?
Have you established clear expectations with your manager?
Do you have work-life boundaries that work for you?

If you can answer yes to most of these, you've successfully navigated your first 90 days. If not, you still have time to course-correct.

When the First 90 Days Reveal Red Flags

Here's something important: sometimes your first 90 days reveal that this job isn't what you thought it would be.

Pay attention to:

Promises that aren't being kept
Cultural mismatches that feel fundamental
Work that's misaligned with your goals
People or processes that are deeply dysfunctional
Gut feelings that something is wrong

We'll talk more about knowing when to leave in Part 8, but if you're seeing serious red flags in your first 90 days, don't ignore them. Trust your instincts.

At the same time, give it the full 90 days before making decisions. Almost everyone experiences some "what did I get myself into" moments in a new role. The question is whether those moments are temporary adjustment pain or signals of fundamental problems.

The Real Goal: Setting Up Your Stepping Stone

Remember: the goal of the first 90 days isn't just to survive probation or prove you can do the job.

The goal is to set yourself up to turn this role—whatever it is—into a stepping stone toward your dream career.

That means:

Building skills that serve your long-term goals
Creating opportunities beyond your job description
Establishing relationships that will help you later
Positioning yourself for growth and visibility
Learning what you want more of and less of in your career

Even if this job isn't your dream job, you can use these first 90 days to extract maximum value from the experience.

That's what I did at Boeing. The role wasn't my ultimate goal, but I used those first 90 days to position myself to join the ML team, take on the cybersecurity focal role, and manage interns. Each of those experiences helped me clarify my career goals and build skills that serve me today.

Your first 90 days aren't just about proving you deserve to be there. They're about setting up everything that comes next.

How did your first 90 days go in your current or most recent role? What do you wish you'd known going in? I'd love to hear about your onboarding experiences—connect with me on LinkedIn or follow @code_with_kate for more insights on building a career that actually works for you.

Previously in this series:

Coming up next:

Part 5: "Making the Most of Where You Are" - Turning any job into a stepping stone toward your goals

Kate Emery