Cheat sheet · Specialise
QA and test automation cheat sheet (API testing)
Opens with creditsFor testers who want to specialise in API testing with Postman and JavaScript, from manual test design to collections and code that run in CI. Use it to revise HTTP, status codes, test scripts, schema checks, contract tests and API security basics.
Curated by Tauseef Fayyaz9 chapters76 concepts172 glossary termsChapters
9 chapters · 76 concepts
1Testing fundamentalsWhat testing is for, where it sits in how software is built, and the vocabulary every QA conversation uses.8 concepts
- 1Why we testTesting is running software, or examining its artefacts, to find defects and to give people evidence about its quality so they can decide whether to release it.
- 2SDLC and STLCThe SDLC is how a team takes a product from idea to release (plan, design, build, test, release, maintain).
- 3Verification and validationVerification asks whether the product was built as specified.
- 4Test levelsUnit tests check one small piece of code.
- 5Functional and non-functional testingFunctional testing checks what the system does: features, rules and outputs.
- 6Test pyramidA model for balancing a suite: many fast unit tests at the bottom, fewer integration and API tests in the middle, and a small number of end-to-end UI tests at…
- 7Risk-based testingChoosing what to test, and how deeply, by the likelihood that an area fails and the impact if it does.
- 8Seven testing principlesWidely taught principles: testing shows the presence of defects, not their absence; exhaustive testing is impossible; test early; defects cluster; tests wear…
8 in this chapterOpen this chapter2Manual testing done wellTurning requirements into test ideas, testing with a plan and curiosity, and writing bug reports that developers act on.11 concepts
- 1Requirements analysisReading a user story or specification before any code exists and asking questions: what happens on errors, at limits, with empty input, for which users.
- 2Equivalence partitioningSplitting possible inputs into groups the system should treat the same way, then testing one value from each group.
- 3Boundary value analysisTesting the values at and next to the edges of each partition, where off-by-one mistakes live.
- 4Decision tablesA table listing combinations of conditions and the expected result for each, used when a rule depends on several inputs at once.
- 5Test cases and checklistsA test case gives preconditions, steps, test data and an expected result.
- 6Exploratory testingDesigning and running tests at the same time, learning as you go, usually in a timed session guided by a charter such as "Explore checkout with expired cards to…
- 7Bug reportA record of a problem with a clear title, steps to reproduce, expected and actual results, environment details and evidence such as screenshots, logs or a…
- 8Severity and prioritySeverity is how badly the bug affects the system.
- 9Bug life cycleThe states a bug moves through: new, triaged, in progress, fixed, ready for retest, then closed or reopened.
- 10Smoke, sanity and regression testingA smoke test is a quick check that a build works at all.
- 11Test management toolsTools that store test cases, plan test runs, record results and link them to requirements and bugs.
11 in this chapterOpen this chapter- Web and API basicsHow browsers and servers talk, how to watch that traffic, and how to check the data behind the screen.8 conceptsOpens with credits
- Programming for testersThe language skills automation needs: data, logic, functions, async code or classes, packages, Git and assertions.7 conceptsOpens with credits
- API testing in depthTesting APIs with Postman collections and scripts, running them from the command line, and moving into schema checks, code-based tests and contract tests.9 conceptsOpens with credits
- Maintainable suitesDesigning test code that stays cheap to change: good structure, data-driven cases, independent tests and a plan for flakiness.7 conceptsOpens with credits
- CI and reportingRunning the suite automatically on every change, in parallel, against the right environment, with reports people read.8 conceptsOpens with credits
- Performance, accessibility and securityThe awareness every tester needs beyond functional checks: basic load tests, accessibility checks and a safe first look at security.10 conceptsOpens with credits
- Your QA careerThe roles, the certificate question, the proof of work that gets interviews and the path from QA into SDET.8 conceptsOpens with credits
- 10Glossary, A to ZEvery concept in the sheet and the smaller terms it uses, in one list.172 terms
About this sheet
Manual testing to automated suites.
Related on Sefism
Picked from the other libraries by shared topics.
Best practices
See all- Software Testing Best PracticesTesting best practices for unit, integration and end-to-end tests: test design, test doubles, flaky tests, coverage and fast CI, with examples in TypeScript and Python.
- CI/CD Best PracticesBuild pipelines that are fast, trustworthy and safe to deploy from: trunk-based flow, fast tests, locked-down workflows, signed artifacts, canaries and DORA metrics.
Checklists
See all- LLM Evaluation ChecklistAn LLM evaluation checklist: success criteria, eval datasets, code and model graders, judge calibration, agent evals, safety tests and production monitoring, with how to verify each check.
- Data Quality ChecklistA data quality checklist for warehouse tables: ownership, freshness, volume, schema, nulls, uniqueness, referential checks, anomaly monitoring and data incidents, with how to verify each.
Project structures
See all- React with Vite (TypeScript) project structureFor developers building a single-page React app that talks to a separate backend: an orders dashboard with auth, routing, server data, forms and tests. Product code is grouped by feature under src/features, shared pieces live in components and lib, and src/app wires providers, routes and guards together.
- Next.js (App Router) project structureFor React developers building a real web front end with Next.js: a shop dashboard with public pages, sign-in, orders and products, talking to a separate backend API. The app folder holds routes only, product code lives in feature folders, server-only code sits in src/server, and the browser side gets a proper React setup: providers, TanStack Query, forms with React Hook Form and Zod, and tests from unit to end-to-end.
- Angular project structureFor developers building a structured single-page app with Angular, the framework many enterprise and services companies use. The example is an orders dashboard with a login: standalone components, signals for state, typed forms, lazy-loaded feature routes, and a small core and shared layer around feature folders, grown from the ng new scaffold to a repository a team can run for years.
Career questions
See all- How do I know if code written by an AI tool is actually correct?You check it the same way you check any code, but more carefully: read the whole diff, confirm every function and package exists, run it against tests that could fail, especially one you wrote yourself, try the edge cases, and make sure you can explain every line. Correct means proven by evidence, not "the tool said it works".
- What does an AI evals engineer do?An AI evals engineer designs the tests that tell a team whether an AI system is good enough: the datasets, the scoring (code checks, human review, or a model as a judge), and the process that runs them on every change. It is a real and growing specialism inside AI engineering, and a strong angle for juniors because few people do it well.
- How do I move from QA to software development?Use test automation as the bridge. Write more and better code in your QA role, pick one development stack that matches your product, take small development tasks inside your current team, and ask for an internal move before you apply outside. Your testing mindset is an advantage, not something to hide.
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