Roadmap

Senior Software Engineer

Skills every developer needs, in any language: code design, testing, data and distributed systems.

22 of 26 lessons readyInterview questions (30)Practice exam

Must know You will not get hired without it.Good to know An extra plus.Specialist Only for special roles.

1

Good code

Code the team can read, test and change.

Must knowClean CodeGood names, small functions, readable codeReady Must knowSOLIDFive basic object-oriented design rules, with examplesReady Good to knowDesign patternsStrategy, Decorator, Factory, Mediator and moreReady Good to knowDependency InjectionService lifetimes and common mistakesReady Must knowCode reviewWhat to look for and how to give feedbackReady

2

Algorithms and concurrency

Fast and correct code, even when many things run at once.

Must knowAlgorithms and data structuresTime complexity (Big O), arrays, hash maps, trees, search and sortingSoon Must knowConcurrencyThreads, locks, race conditions, deadlocksSoon

3

Data

Store data correctly and read it fast.

Must knowSQL and indexesQuery plans, the right index, paging on big tablesReady Must knowTransactions and isolation levelsLost updates, deadlocks and locksReady Must knowCaching patternsCache-aside, cache invalidation, stampedeReady SpecialistNoSQLMongoDB and when to use it instead of SQLReady

4

APIs and security

An API that is correct, safe and reliable.

Must knowAPI designREST, HTTP status codes, pagination, versioningSoon Must knowSecurityOWASP Top 10, secret management, encryptionReady Good to knowAuthentication and authorizationJWT, OAuth2, OpenID Connect and policiesReady Must knowIdempotencyOne request, any number of times, one resultReady

5

Testing and delivery

Change and release without fear.

Must knowUnit tests with xUnitWhat a good test looks like, mocks and fakesReady Must knowIntegration testsTestcontainers and WebApplicationFactoryReady Good to knowTDDTest first, then code: red, green, refactorReady Must knowGit and version controlBranches, merge, rebase, a clean historySoon Must knowCI/CDPipelines, automated tests, safe deploysReady Good to knowDockerSmall images, multi-stage builds, layersReady

6

In production

Know what happens when the code runs, and handle failures.

Must knowStructured loggingSerilog, log levels, correlation IDsReady Good to knowMetrics and alertsPrometheus, Grafana and good alertsReady Good to knowResilience with PollyRetry, circuit breaker, timeout and retry stormsReady Good to knowSystem designHorizontal scaling, load balancing, sharding, replicasReady Good to knowEstimation and planningEstimating work, splitting big tasks, riskReady