Hacker News: jsw

New comment by jsw in "PgDog is funded and coming to a database near you"

jsw — Wed, 10 Jun 2026 19:35:18 +0000

Interesting! We interact with the low-level APIs too vs the SDK, also: an IO scheduler for request batching and conn management, request hedging, full MVCC transactions, etc. We store raw bytes in DDB and manage schema/etc elsewhere. Curious if there is other low-hanging fruit, or not so low, you found that we haven't discovered yet.

New comment by jsw in "PgDog is funded and coming to a database near you"

jsw — Wed, 10 Jun 2026 19:10:42 +0000

Curious how the DB startup with Dynamo at its core went. We use it heavily. The primary tricky thing for us at the moment is aligning pricing with workload value.

AWS ExtendDB, open-source DynamoDB API with pluggable backends

jsw — Thu, 21 May 2026 02:30:06 +0000

Article URL: https://aws.amazon.com/blogs/database/introducing-extenddb-an-open-source-dynamodb-compatible-adapter-with-pluggable-storage-backends/

Comments URL: https://news.ycombinator.com/item?id=48217095

Points: 3

# Comments: 1

New comment by jsw in "Emacs-libgterm: Terminal emulator for Emacs using libghostty-vt"

jsw — Thu, 02 Apr 2026 15:29:15 +0000

Do you have any of your fixes publicly available?

New comment by jsw in "Term-keys – Lossless keyboard input for Emacs"

jsw — Sun, 07 Dec 2025 18:09:51 +0000

Regardless, that’s kind of the beauty of this project: term-keys generates the terminal config file based on all your bespoke keybindings for you. Would probably be easier to setup than you imagine.

New comment by jsw in "Term-keys – Lossless keyboard input for Emacs"

jsw — Sun, 07 Dec 2025 00:12:42 +0000

MacOS user here. So many times over the last decade I’ve journeyed to get terminal Emacs working with my litany of weird keybindings. But I always end up back in the GUI.

I switched to Colemak about 15 years ago and thought it would be a good idea to rethink all my Emacs keybindings, since my muscle memory was shot in that transition. (I don’t recommend this in hindsight.)

I have yet to get a terminal working fully like the GUI. Partly because I refuse to install a third-party key mapper.

Anyway, just tried this and Alacritty. It’s the closest I’ve got to fully working. My guess is another hour of tweaking and I could maybe get all the way there.

New comment by jsw in "Monotonic and wall clock time in the Go time package"

jsw — Fri, 25 Jul 2025 18:53:22 +0000

For simple high-frequency time deltas, I've found this function wins on the perf front:

  //go:linkname nanotime runtime.nanotime
  func nanotime() int64

New comment by jsw in "An Interactive Guide to Rate Limiting"

jsw — Sun, 08 Jun 2025 15:35:56 +0000

Love the simplicity and elegance of the design to address this problem.

New comment by jsw in "An Interactive Guide to Rate Limiting"

jsw — Fri, 06 Jun 2025 18:02:44 +0000

I mentioned this in another place on this thread, but a simple AIMD algorithm paired with a token bucket is surprisingly effective at dynamically adjusting to available capacity, even across a fleet of services not sharing state other than the contended resource.

Pretty easy to pair AIMD with token bucket (eg https://github.com/webriots/rate)

New comment by jsw in "An Interactive Guide to Rate Limiting"

jsw — Fri, 06 Jun 2025 15:48:25 +0000

I’ve found the AIMD algo (additive increase, multiplicative decrease) paired with a token bucket gives a nice way to have a distributed set of processes adapt to backend capacity without centralized state.

Also found that AIMD is better than a circuit breaker in a lot of circumstances too.

Golang lib of the above https://github.com/webriots/rate

Show HN: A Go library to rate limit across millions of users

jsw — Thu, 15 May 2025 16:38:52 +0000

I built a thread-safe rate limiting library for Go that's lock-free with zero allocations on the hot path. It features multiple strategies including classic token bucket and TCP-inspired AIMD algorithm for dynamic rate adjustments. Optimized for high-throughput systems with memory efficiency (packed uint64 representation) and precise per-entity limiting.

When building high-throughput services, I kept hitting the same problem with existing rate limiting libraries - they break down with high-cardinality identifiers. Try rate limiting millions of unique user IDs, API keys, or IPs and you'll face:

  1. Memory consumption exploding linearly with cardinality
  2. Lookup performance degrading as hash tables grow
  3. Contention killing throughput under load
  4. GC pressure from constant allocations

I built rate specifically to solve this:

  - Fixed memory footprint regardless of cardinality (configurable power-of-2
  buckets)
  - Sub-microsecond, zero-allocation operations even at scale
  - Lock-free design using atomic operations
  - Collision probabilities you can reason about mathematically

This means you can rate limit by user ID, device ID, API key, IP address or any other high-cardinality identifier without performance penalty. The benchmark numbers tell the story: even with thousands of distinct IDs hitting the limiter concurrently, operations complete in 1-15ns with zero allocations.

Comments URL: https://news.ycombinator.com/item?id=43996751

Points: 2

# Comments: 0

New comment by jsw in "When to use Bazel?"

jsw — Tue, 13 Sep 2022 22:48:44 +0000

Bazel is a fully reproducible and hermetic build system. A lot of painstaking work goes into it producing the exact same artifacts build after build. And that provides some interesting properties that you can leverage for artifact caching, deployments, and CICD.

We very happily runny a polyglot monorepo w/ 5+ languages, multiple architectures, with fully reproducible artifacts and deployment manifests, all deployed to almost all AWS regions on every build. We update tens of thousands of resources in every environment for every build. The fact that Bazel is creating reproducible artifacts allow us to manage this seamlessly and reliably. Clean builds take an hour+, but our GH self-hosted runners often complete commit to green build for our devs in less than a minute.

The core concept of Bazel is very simple: explicitly declare the input you pass to a rule/tool and explicitly declare the output it creates. If that can click, you're half way there.

New comment by jsw in "US Senate votes unanimously to make daylight savings time permanent"

jsw — Tue, 15 Mar 2022 19:52:14 +0000

I wish “Prevailing Time” would catch on. Eg PPT

New comment by jsw in "A Better Model for Stacked Pull Requests"

jsw — Sat, 24 Apr 2021 03:27:36 +0000

Mergify just introduced a “speculative merge queues[1]” feature that does something very similar.

[1] https://blog.mergify.io/announcing-speculative-merge-queues

New comment by jsw in "Google Fonts Analytics"

jsw — Wed, 19 Feb 2020 19:27:42 +0000

That sweet, sweet traffic data.

New comment by jsw in "Why Google Stores Billions of Lines of Code in a Single Repository (2016)"

jsw — Sat, 11 Jan 2020 17:59:51 +0000

I've always been curious about the general directory structure they use for this. Does anyone have insight?

New comment by jsw in "Monorepo is great if you're really good"

jsw — Tue, 30 Jul 2019 16:40:26 +0000

I’m firmly on team monorepo, and I agree great tooling is an absolute requirement. We use Bazel + AWS CodeBuild with local caching. We have an average incremental CI build of our monorepo that’s under 45 seconds. Clean build 30+ minutes.

New comment by jsw in "Robinhood Stored Passwords in Plaintext"

jsw — Wed, 24 Jul 2019 22:36:26 +0000

The AWS Cognito User Pool Authentication Flow utilizes an augmented PAKE (SRP). I imagine there are a number of major sites that use Cognito along with the SRP auth flows baked into their std libs. I know I've used it a number of times.

New comment by jsw in "What if we could see all concurrency bugs in the debugger?"

jsw — Fri, 12 Jul 2019 22:09:13 +0000

TLA+ specs explore all state spaces of concurrent processes. Avoiding state explosions is something you need to be conscious of when building those. The modeling required also takes some learning investment. Curious if this can really pull off something like a TLA+ state exploration and invariant violation detection with real-world code.

A Change Data Capture Pipeline from PostgreSQL to Kafka

jsw — Thu, 30 Mar 2017 16:53:03 +0000

Article URL: https://www.simple.com/engineering/a-change-data-capture-pipeline-from-postgresql-to-kafka

Comments URL: https://news.ycombinator.com/item?id=13996988

Points: 1

# Comments: 0