FreeCareerPathEnter Foundation
Foundations
For starting from zero. This roadmap gets you from no programming background to a small, finished project you can talk about in an interview — without pretending you already know what a career changer or self-taught beginner rarely does.
Spider Multiverse
Walk the multiverse, find missions in the world, and watch it respond to what you actually finish. Same lessons, same progress as the list below.
Foundations progress: 0/41 complete (0%)
616 · The Origin
Code SenseProgramming Foundations
- What happens when you load a web pageThe request/response loop behind every website — the mental model everything else builds on.
- Set up a real dev environmentA code editor, a terminal, and version control — configured once, used every day after.
- Command line basicsNavigate, create, and move files without a mouse — every real workflow assumes this.
- Variables, types, and control flowStoring data and making decisions — the two things every program does.
- Functions and thinking in small piecesBreaking a problem into named, reusable pieces instead of one long script.
- Reading code you didn't writeThe most underrated beginner skill — you'll spend more time reading code than writing it.
- Scope a project you can actually finishPick something small enough to finish in days, not months.
- Build without a tutorial holding your handUse docs and search, not a step-by-step video, to build this one.
- Debug systematically instead of guessingForm a hypothesis, test it, narrow it down — not random changes until it works.
- Put your project on GitHubVersion control your work and make it visible — this is table stakes, not optional polish.
- Write a README a stranger can followWhat it does, why, and how to run it — assume the reader has 30 seconds.
- Ask for feedback that's actually usefulSpecific questions get specific answers — 'is this good?' doesn't.
42 · Glitch City
Bug SenseDebugging + Git
1610 · The Connected Web
Web ArchitectSQL, APIs + Testing
- HTTP Requests and Status CodesRead a request's method, URL, headers and status code and tell which side broke it.
- Designing a JSON APIDesign routes for a resource, validate input and return the status code each situation calls for.
- Auth Tokens and CORSProtect API routes with a token, choose between 401 and 403, and configure CORS without opening a hole.
- Querying Data with SQLWrite SELECT queries that filter, sort, join and count rows, and pass user input safely as parameters.
- Tables, Keys and IndexesDesign linked tables with primary and foreign keys, avoid duplicated data, and add the indexes your queries need.
- Tests You Can TrustWrite unit and integration tests that cover edge cases, fail when the code is wrong, and pass reliably when it is right.
- Data & SQL3 problems from the Foundation Bank, graded through Explain Mode.
- APIs & HTTP3 problems from the Foundation Bank, graded through Explain Mode.
- Testing & Code Quality2 problems from the Foundation Bank, graded through Explain Mode.
928 · Machine Realm
System BuilderBackend Primitives
- Queues and Background JobsMove slow work like emails and image resizing off the request into a queue, and write job handlers that are safe to run twice.
- Rate Limiting RequestsProtect an API from abuse and runaway costs by limiting requests per user or key and answering over-limit calls with 429 and Retry-After.
- Caching Without Stale DataAdd a cache-aside cache to a slow read, choose a sensible TTL, and invalidate it on writes so users never see stale or someone else's data.
- Retries, Backoff and Scheduled JobsRetry only the failures worth retrying, with exponential backoff, jitter and a limit, and write scheduled jobs that are safe to run twice.
- Connection Pools and TimeoutsShare database connections through a pool, always release them, and set timeouts so one slow dependency cannot hang your whole server.
- Circuit Breakers and Failing FastStop a failing dependency from dragging your whole service down by failing fast with a circuit breaker, a fallback, and honest health checks.
- Backend Primitives6 problems from the Foundation Bank, graded through Explain Mode.
3145 · Broken Timeline
Production SenseConcurrency + Production Debugging
- Async Code and the Event LoopYou will be able to write async/await code that runs independent work in parallel, waits where it must, and never loses an error to a forgotten await.
- Race Conditions and Shared StateYou will be able to spot a read-modify-write race in your own code and fix it with an atomic database update, a transaction or a unique constraint.
- Locks and DeadlocksYou will be able to protect shared data with a short-lived lock, lock database rows with SELECT ... FOR UPDATE, and avoid deadlocks by always locking in the same order.
- Logs, Metrics and AlertsYou will be able to add structured logs with request ids, track error rate and p95 latency, and set up alerts that fire when users are actually affected.
- Responding to an IncidentYou will be able to handle a production incident calmly: confirm the impact, stop the damage first, keep people informed, find the cause and write a blameless postmortem.
- Cache Stampedes and Thundering HerdsYou will be able to stop a popular cache key from flooding your database when it expires, using request coalescing, jittered TTLs and stale-while-revalidate.
2099 · AI Frontier
AI ReviewerAI-Assisted Engineering
- Prompting for Useful CodeWrite prompts that give an AI assistant enough context to produce small, correct pieces of code you can check.
- Working with a Coding AgentGive a coding agent a tightly scoped task on a branch, review its diff and run the tests yourself before accepting its work.
- Reviewing AI-Generated CodeReview code you didn't write for correctness, edge cases, error handling and removed checks, and explain it before you ship it.
- Spotting Hallucinated APIsRecognise invented functions, options and packages in AI-written code, and confirm them against the docs, the registry and a small running example.
- Securing AI-Written CodeSpot the insecure patterns AI assistants commonly produce, keep secrets out of prompts, and run a short security check before merging.
- Verifying with Tests and EvidenceProve AI-written code works with tests that would fail if it were wrong, edge-case checks and a look at the running app.