sam.lindqvist

Infrastructure engineer. I make deploys dull.

pinned

samlq/tidewater

Public

Back-pressure for job queues - a queue that says no before the database does.

queues
postgres

Go
5.1k stars
290 forks

samlq/sqlite-cdc

Public

Change data capture for SQLite - stream every write to Kafka, NATS or a file.

sqlite
cdc

Rust
1.9k stars
77 forks

samlq/dotfiles

Public

zsh, tmux and neovim - set up in one command on a fresh machine.

neovim
tmux

Shell
412 stars

activity --last 12 months

1,284commits

312pull requests merged

7.4kstars across repos

stack

Go 5 of 5 8 yrs
PostgreSQL 5 of 5 9 yrs
Kubernetes 4 of 5 6 yrs
Rust 3 of 5 3 yrs
Nix 2 of 5 1 yr

git log --career

Staff engineer, build and release

Globex

2022 - today
Site reliability engineer

Initech

2017 - 2021
B.Sc. Computer Science

KTH Stockholm

2014 - 2017

writing

2026-09-14 Your queue needs a no
Back-pressure explained with a coffee shop and a very long line.
2026-05-02 Twelve months without a 3 a.m. page
What we changed in on-call, and what we deleted.
2025-11-20 SQLite is a fine message bus (until it is not)
Notes from building sqlite-cdc.

samlq/tidewater

Back-pressure for job queues - a queue that says no before the database does.

Public queues postgres

go get github.com/samlq/tidewater

go: added github.com/samlq/tidewater v2.4.0

tidewater bench --rps 5000

accepted 4,812/s · refused 188/s · p99 41 ms

Language: Go
Stars: 5.1k
Forks: 290
Licence: MIT
Since: 2021

why it exists

At Initech our job queue accepted everything, and the database paid for it: every spike became a backlog, every backlog a page at 3 a.m. Retries made it worse.

what I did

I wrote it on weekends, then at work: a queue that measures how long the database takes to answer and stops taking jobs before it drowns. Producers get a clear "not now" with a retry time instead of a timeout.

Dark, choppy water of the open sea — The name: water that pushes back

what it changed

Five years and 290 forks later it runs in front of Postgres at companies of every size. At Globex it took queue incidents from eleven a quarter to none.