How a Brazilian SWE in the US Prepped System Design in English
Six years of engineering. The gap was sounding senior - behavioral and system design - in English on a US interview loop.
What this case shows
A Brazilian software engineer in Tennessee practised Banco Itaú migration stories and disagreement rounds in English - fluency and senior framing, no offer claimed.
At a glance
| Role | Software engineer (~6 years) |
|---|---|
| Region | United States (Tennessee) |
| Background | Brazil → US; student visa; sponsorship path |
| Focus | Behavioral + system design |
| Story bank | Monolith → microservices (Itaú) |
| Outcome | Senior framing and structured disagreement answers |
Timeline
Brazil → US
Focus
Monolith → microservices
Outcome
Behavioral + system design
“I get blocked when I speak. I know the work - I just don’t sound senior enough in English.”
Profile
A software engineer from Brazil, based in Tennessee after moving to the US, preparing for interviews that mix general, behavioral, technical, and system design. Roughly six years’ experience; aiming to sound fluent and senior rather than blocked mid-answer. Classes deep-dived a Banco Itaú monolith-to-microservices migration and disagreement / buy-in stories.
Pain Points
- Confidence drops; she feels blocked mid-sentence
- Does not sound senior enough under pressure
- Pronunciation: reliable, Latin America
- “Tried to change the culture” needed ownership vs influence wording
- Passive vs active on buy-in (“I needed to get a buy-in”)
- Results without magnitude (time to market, tech debt)
Goals
- All interview parts: general, behavioral, technical, and system design
- Sound senior: influence, buy-in, downtime, resistance to change
- Deep technical story with metrics (DORA / developer experience metrics when honest)
- Structured answers when someone disagreed
- Sponsorship-ready interview English
Lesson Notes
These are the classes we actually ran, not a generic curriculum. Each one started from a real interview question.
Class 1
Technical story
Monolith to microservices - Itaú
- Talk about experience at Banco Itaú: monolithic → microservices
- Decreased tech debt; modularised code; decreased time to market (TTM) for features - add a specific magnitude
- DORA / DevEx metrics when true
- Difficulties: resistance to change; get buy-in; empathy; data-driven approach
- “My approach isn’t to convince - it’s to give stakeholders the data to decide”
Class 2
System + leadership
No downtime and culture language
- How did you ensure no downtime? on-call; touched base regularly; retrospectives
- Get a buy-in; careful with “tried to change the culture” → “I influenced the culture as a team lead”
- Dynamic role; approximately / roughly / as an estimate
- I understood where they were coming from
Class 3
Behavioral
Disagreement story structure
- Tell me about a time someone disagreed with you
- While at … / at the time we faced … / my approach was … / in the end … / as a result …
- Tell me about yourself: reliable pronunciation; Latin America
- Why do you want to work here?
Feedback
Coach notes from those sessions, kept as they were given in class.
Influence vs change the culture
Senior answers own influence. “Tried to change the culture” sounds naive; “influenced as a team lead” is cleaner.
Buy-in is stakeholder work
Resistance to change stays; your job is data and empathy - not winning an argument.
Put a number on TTM
“Decreased TTM” needs a magnitude or the interviewer will ask how you measured it.
Disagreement needs a spoken order
While at → faced → approach → end → result. Don’t restart the timeline on follow-ups.
Common Mistakes
Corrections from live answers, the same patterns that showed up in class.
| Heard in class | Use instead |
|---|---|
| “Relyble” | “Reliable” ruh-lai-uh-bl stress. |
| “Amercia Latin” | “Latin America” Fixed order and pronunciation. |
| “Tried to change the culture” | “I influenced the culture as a team lead” Senior ownership language. |
| “I needed to get a buy in” | “There was resistance to change - I worked to get buy-in” Name the situation, then your approach. |
Before and After
Before coaching
- Sounded junior under pressure
- Culture / buy-in wording weak
- Results without measurement
- Disagreement answers unstructured
After coaching
- Senior influence phrases ready
- Migration story with clearer impact
- Downtime / on-call vocabulary
- Disagreement structure practised
The Result
Clearer senior-sounding English for behavioral and system-design style stories. She could explain the migration and disagreement rounds with more structure. Readiness - not a promised offer - was the goal.
What to practise if you need to sound senior in English
- Rewrite culture lines as influence plus role (team lead), not “tried to change.”
- Add one magnitude to every time-to-market, debt, or downtime claim.
- Practise disagreement with a fixed spoken order.
- Say buy-in and resistance without blaming individuals.
- Record one migration story and cut unfinished sentences.
Why Senior Framing Is Hard in a Second Language
US loops score judgment and ownership as much as architecture. Translating each sentence burns the time you need for buy-in and trade-offs. A practised migration story plus disagreement structure is what keeps you sounding senior when English is under load.
Preparing for a similar path? Read Preparing for a Chat System Design Interview in English.
Learning paths
Practise in the course
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Other engineers practising interview English
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I’ve had the pleasure of practicing English with Mockly and I truly appreciate the progress I’ve made. I highly recommend their services to professionals in tech and beyond. I particularly enjoy the teaching style and the philosophy behind it: “If you enjoy the process, you’ll get it.” The personalized learning plans make every session practical and useful. Their hands-on knowledge and genuine interest in the world of technology will genuinely boost your English skills.
FAQ
Questions
More questions? Email us at contact@mocklyenglish.com.
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