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Software Engineer Interview Questions

Practice 9403 coding, system design and machine learning questions from 546 companies, sorted by role, topic and interview round. Every question has step-by-step hints, a code runner that supports 8 languages and an AI mentor; members also get the full solution walkthrough.

9403
Questions: 546
Companies: 11
Topics: 8
Languages

Showing 1–19 of 19 results

AdobeMediumSoftware Engineer
Implement scalable word count locally
This question evaluates understanding of scalable word-count processing, including tokenization and normalization rules, streaming or external-memory techniques for inputs larger than RAM, and efficient top‑K frequency computation.
Data Manipulation (SQL/Python)Technical Screen
AeoneaMediumSoftware Engineer
Fill missing values with means
This question evaluates proficiency in missing-data imputation and pandas DataFrame manipulation, testing skills in column-wise aggregation, group-wise operations, and edge-case handling within the Data Manipulation (SQL/Python) domain.
Data Manipulation (SQL/Python)Technical Screen
AffirmMediumSoftware Engineer
Analyze Returning Borrowers Across Two Days of Logs
Process two daily loan activity logs to identify users active on both days with diverse loan types, then score them using a configurable trust policy.
Data Manipulation (SQL/Python)Technical ScreenData ManipulationHash TablePython
AirbnbMediumSoftware Engineer
Review a geospatial Python module
This question evaluates proficiency in geospatial data processing and Python code review, including detection of correctness bugs, numerical stability issues, CRS handling, performance optimization, refactoring, testing strategy, and security considerations when working with CSV/GeoJSON datasets.
Data Manipulation (SQL/Python)Technical Screen
AmazonMediumSoftware Engineer
Compute unique visitors per department from clicks
This question evaluates a candidate's skill in data manipulation and deduplication using SQL/Python, specifically mapping hierarchical product metadata to departments and computing unique user counts without double-counting, and is categorized under Data Manipulation (SQL/Python).
Data Manipulation (SQL/Python)Technical Screen
AmazonMediumSoftware Engineer
Manipulate time-series with Pandas groupby
This question evaluates proficiency in time-series data manipulation, including timezone-aware datetime parsing and DST handling, groupby and rolling-window aggregations, resampling to fill calendar gaps, and user-level retention and DAU calculations using idiomatic, vectorized Pandas or SQL operations.
Data Manipulation (SQL/Python)Technical Screen
AppleMediumSoftware Engineer
Explain Python lists, dicts, and concurrency
Explain Python lists, dicts, and concurrency evaluates SQL or pandas logic, joins, grouping, window functions, null handling, edge cases, and validation in a realistic interview setting. A strong answer states assumptions, handles edge cases, explains trade-offs, and shows how to validate the result clearly.
Data Manipulation (SQL/Python)Technical Screen
Bilt RewardsMediumSoftware Engineer
Write SQL to Join Merchants and Triple Restaurant Points
This question evaluates SQL querying and data engineering competencies—specifically JOINs, conditional logic (CASE), ETL staging, data cleaning, indexing, and approximate string matching—within the data manipulation and database domain and emphasizes practical application of SQL for transforming transactional datasets.
Data Manipulation (SQL/Python)Technical Screen
DoorDashMediumSoftware Engineer
Compute courier pay with peak-hour rules
This question evaluates a candidate's data manipulation skills and competency in implementing business rules, including robust error handling, aggregation for per-day totals, minimum-pay enforcement, and time-window (peak-hour) pay adjustments.
Data Manipulation (SQL/Python)Technical Screen
KikoffMediumSoftware Engineer
Parse CSV and format transactions
This question evaluates a candidate's ability to parse and format structured transactional data, emphasizing CSV parsing, trimming whitespace, numeric formatting to two decimal places, and preserving input row order.
Data Manipulation (SQL/Python)Technical Screen
MicrosoftMediumSoftware Engineer
Compute most popular location with weights
This question evaluates a candidate's ability to perform weighted aggregation, data cleaning, tie-breaking logic, and handling of malformed or missing text fields using SQL and/or Python.
Data Manipulation (SQL/Python)Technical Screen
NVIDIAMediumSoftware Engineer
Implement 2D convolution using NumPy slicing
This question evaluates a candidate's proficiency with array manipulation and vectorized numerical computation using NumPy, focusing on 2D convolution concepts such as slicing, broadcasting, and filter application.
Data Manipulation (SQL/Python)Technical Screen
OpenAIMediumSoftware Engineer
Parse and build binary data in Python
This question evaluates proficiency in binary data handling and serialization/deserialization in Python, including little-endian integer encoding, length-prefixed payloads, robust error handling for short reads and invalid lengths, and testability and performance considerations.
Data Manipulation (SQL/Python)Technical Screen
OracleMediumSoftware Engineer
Classify Tree Nodes in SQL
Tests the ability to write conditional logic and subqueries/joins in SQL to classify hierarchical tree nodes into 'Root', 'Inner', or 'Leaf'.
Data Manipulation (SQL/Python)Technical ScreenSQLPostgreSQLTrees
StripeMediumSoftware Engineer
Compute costs with validation and sorting in Python
This question evaluates proficiency in data validation, numeric robustness, error handling, aggregation, per-item cost computation and deterministic sorting within Python-based data manipulation tasks, and it belongs to the Data Manipulation (SQL/Python) domain.
Data Manipulation (SQL/Python)Technical Screen
StripeMediumSoftware Engineer
Design payment-to-invoice matcher with priorities
This question evaluates parsing and data modeling skills, deterministic matching algorithms with prioritization and tie-breaking, handling monetary values as integer cents, and the ability to design comprehensive test suites for edge cases.
Data Manipulation (SQL/Python)Technical Screen
StripeMediumSoftware Engineer
Reconcile Monthly Bank-Account Balances Across Two Datasets
Implement a reconciliation function that joins internal ledger balances with external bank statements for a target month, categorizing discrepancies while strictly distinguishing between missing records and zero balances.
Data Manipulation (SQL/Python)Technical ScreenData ManipulationHash TableAccounting
TikTokMediumSoftware Engineer
Discuss Python mutability, copying, and GIL
This question evaluates understanding of Python mutability and copying semantics — including how mutable versus immutable objects affect function arguments and container behavior — and knowledge of the Global Interpreter Lock (GIL) and concurrency models.
Data Manipulation (SQL/Python)Technical Screen
TikTokMediumSoftware Engineer
Write complex SQL for cohorts and retention
This question evaluates advanced SQL and data-engineering competencies such as cohort and retention analysis, deduplication, timezone normalization, last-touch attribution, aggregate revenue calculations, and effective use of window functions in the Data Manipulation (SQL/Python) domain.
Data Manipulation (SQL/Python)Technical Screen