Forem: Adrian Brad

Go queue v1.7.0: a new Delay queue for timers, retries, and TTLs

Adrian Brad — Tue, 21 Apr 2026 09:18:46 +0000

I just tagged v1.7.0 of github.com/adrianbrad/queue, a thread-safe generic queue package. The headline feature is a new Delay queue.

What is Delay?

Delay is a priority queue where each element becomes dequeuable at a deadline computed by a caller-supplied function at Offer time. Get returns ErrNoElementsAvailable until the head is due; GetWait sleeps until it is.

type task struct {
    id    int
    runAt time.Time
}

delayQueue := queue.NewDelay(
    []task{
        {id: 1, runAt: time.Now().Add(20 * time.Millisecond)},
        {id: 2, runAt: time.Now().Add(5 * time.Millisecond)},
    },
    func(t task) time.Time { return t.runAt },
)

// Blocks until the earliest-deadline element is due.
next := delayQueue.GetWait()
fmt.Println(next.id) // 2

Useful for retry scheduling, TTL expiry, timer wheels, and similar patterns where work should become visible at a future wall-clock time.

Implementation notes

Min-heap by deadline, written directly on a typed slice instead of via container/heap. pprof showed container/heap's any-boxing accounted for most of the allocations, so steady-state offer/get is now zero-alloc.
GetWait uses sync.Cond + time.AfterFunc so "head is due" and "queue state changed" compose under a single Wait.
Peek returns the head regardless of whether its deadline has passed (matches java.util.concurrent.DelayQueue.peek).

Five queues, one interface

Delay joins Blocking, Priority, Circular, and Linked. All satisfy the same Queue[T comparable] interface, so you can swap implementations without changing call sites. The README has a small decision table for picking one.

Bonus: v1.6.0 shipped a lot

Since the last post I also tagged v1.6.0, a heavy batch of correctness and performance work:

Priority.MarshalJSON was emitting elements in arbitrary heap-array order; now emits in priority order.
Reset on Blocking, Circular, and Priority now honours capacity and zeros dropped slots (pointer T was leaking).
Blocking switched from Signal to Broadcast, removing a fragile cascade in PeekWait.
Linked grew an internal node free list; steady-state offer/get dropped from 16 B / 1 alloc to 0.
Capacity validation at construction time (panics with a clear message instead of a cryptic slice panic later).

Feedback welcome

Repo: github.com/adrianbrad/queue
Docs: pkg.go.dev/github.com/adrianbrad/queue

Thanks for reading.

Introducing PrivateBTC: A Go package providing an intuitive TUI and a streamlined API.

Adrian Brad — Tue, 31 Oct 2023 09:08:08 +0000

With PrivateBTC you can launch and manage your Bitcoin private network with ease. Execute and replace transactions by fee, mine blocks, and programmatically delve into chain reorganizations.

https://github.com/adrianbrad/privatebtc

Announcing v1.3.0 of my queue package implemented in Golang

Adrian Brad — Tue, 24 Oct 2023 20:41:24 +0000

https://github.com/adrianbrad/queue

I'm happy to announce that I've released v1.3.0 of my #queue #golang package: A Linked Queue implementation was added, complementing the Circular, Blocking, and Priority queues. All structures align with the standard Queue interface.

The package also contains various artifacts that could interest a broader audience. These artifacts include: CI scripts(coverage, lint, testing), golang-ci lint config file, commitizen, example tests, benchmarks and documentation provided by godoc.

I released v1.2.0 of my queues package implemented in Golang.

Adrian Brad — Wed, 19 Apr 2023 12:52:23 +0000

https://github.com/adrianbrad/queue

A Circular Queue implementation is now available. Blocking and Priority queues were previously available. All implementations satisfy the Queue interface provided by the package.

Parallel Go tests executed against a PostgreSQL database running on Docker

Adrian Brad — Tue, 19 Apr 2022 05:12:16 +0000

Hello, I published an article explaining explaining how to run your Go tests in parallel against a PostgreSQL DB running on Docker. The PSQL container is created and destroyed programmatically, with Go, before and after running the tests.

Medium article: https://adrianbrad.medium.com/parallel-postgresql-tests-go-docker-6fb51c016796

Github repo with examples: https://github.com/adrianbrad/psql-docker-tests-example