Learn Go like a backend engineer.Real tests. Race detector on. No videos.
Three courses that take a working programmer from Go idioms to gRPC and pprof. Every exercise is graded by real Go tests — concurrency under the race detector — so “it works” is never a vibe. Built for people who already program.
// merge fans results from n workers into one channel.
// The grader runs this under -race — a data race is a failing test.
func merge(chs ...<-chan int) <-chan int {
out := make(chan int)
var wg sync.WaitGroup
for _, ch := range chs {
wg.Add(1)
go func() {
defer wg.Done()
for v := range ch {
out <- v
}
}()
}
go func() {
wg.Wait()
close(out)
}()
return out
}Fundamentals & Concurrency
Go for people who already program — idioms, slices, maps and structs, errors and interfaces, and correct concurrency graded under -race.
HTTP, Data & Testing
Production HTTP services on net/http, data access via repository interfaces, and Go-team testing — table-driven, httptest, benchmarks.
gRPC, Performance & Deploy
The production tier — gRPC service design, pprof-driven performance, tiny-container deployment, and a load balancer and KV-store capstone.
The tests decide, not vibes
Your code runs against real Go tests with the race detector on. Pass/fail is deterministic — the AI never grades you.
It adapts to you
Struggle on a concept and the game diagnoses why and builds targeted practice. Already know channels? It moves you up instead of making you sit through it.
Ship real backends
Capstones like a load balancer and a KV store, with a senior-engineer code review — the answer to tutorial hell. Ship a portfolio, not just streaks.
Your first passing Go test is minutes away.
Start the Go track — freeFree tier is genuinely free — every banked exercise is playable. We gate AI help and fresh generation, never the content.