ALalgorithmsRcool·Jun 6, 2026Submission
Deterministic Implementation of a .NET Runtime
3 points · Open discussionWoofWare
WoofWare.PawPrint
F#2025–2026
WoofWare / WoofWare.PawPrint
WoofWare.PawPrint
An implementation of a deterministic .NET runtime, which can fuzz over all sources of nondeterminism; also some nascent tools for the symbolic analysis of IL.
2Distinct people
4Mentions
0Explicit recommenders
9GitHub stars
What to know before exploring
What it is
An implementation of a deterministic .NET runtime, which can fuzz over all sources of nondeterminism; also some nascent tools for the symbolic analysis of IL.
GitHub
Where it is used
No documented product use has been verified yet.
What people are saying
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Also in these discussions
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This week on Hacker News
Nov 7–Nov 14 UTC · Direct repository links and separately labeled related project stories. Indexed through 11/14/2026, 5:04:57 PM UTC.
No direct repository links were found in the indexed HN discussions over the past seven days. Older discussions are available below.
Mentions over time
HN mentions by month4 dated mentions
Observed mentions: 2025-06-29 22:04:33 UTC to 2026-06-06 19:39:08 UTC.
Counts come from the repository’s dated source evidence. Index cutoff: 2026-11-02 08:16:59 UTC.
View mention counts and date ranges
| Period | Start (UTC) | End (exclusive, UTC) | Mentions | Submissions | Comments |
|---|---|---|---|---|---|
| Jun 2025 | 2025-06-01 00:00:00 UTC | 2025-07-01 00:00:00 UTC | 1 | 0 | 1 |
| Jul 2025 | 2025-07-01 00:00:00 UTC | 2025-08-01 00:00:00 UTC | 0 | 0 | 0 |
| Aug 2025 | 2025-08-01 00:00:00 UTC | 2025-09-01 00:00:00 UTC | 0 | 0 | 0 |
| Sep 2025 | 2025-09-01 00:00:00 UTC | 2025-10-01 00:00:00 UTC | 0 | 0 | 0 |
| Oct 2025 | 2025-10-01 00:00:00 UTC | 2025-11-01 00:00:00 UTC | 0 | 0 | 0 |
| Nov 2025 | 2025-11-01 00:00:00 UTC | 2025-12-01 00:00:00 UTC | 1 | 0 | 1 |
| Dec 2025 | 2025-12-01 00:00:00 UTC | 2026-01-01 00:00:00 UTC | 0 | 0 | 0 |
| Jan 2026 | 2026-01-01 00:00:00 UTC | 2026-02-01 00:00:00 UTC | 0 | 0 | 0 |
| Feb 2026 | 2026-02-01 00:00:00 UTC | 2026-03-01 00:00:00 UTC | 0 | 0 | 0 |
| Mar 2026 | 2026-03-01 00:00:00 UTC | 2026-04-01 00:00:00 UTC | 0 | 0 | 0 |
| Apr 2026 | 2026-04-01 00:00:00 UTC | 2026-05-01 00:00:00 UTC | 0 | 0 | 0 |
| May 2026 | 2026-05-01 00:00:00 UTC | 2026-06-01 00:00:00 UTC | 1 | 0 | 1 |
| Jun 2026 | 2026-06-01 00:00:00 UTC | 2026-07-01 00:00:00 UTC | 1 | 1 | 0 |
What Hacker News says
4 sourcesMain project is a deterministic .NET runtime (https://github.com/Smaug123/WoofWare.PawPrint). Today I upgraded it to net10, which has naturally caused dozens of regressions which Claude is beavering away at.
Side project is my own agent harness, https://github.com/Smaug123/writ , which is being built sandbox-first and with Nix as a first-class citizen. Obviously everyone has to write their own agent harness as a rite of passage.
In Ask HN: What are you working on? (May 2026)Unwound a couple of things from the stack!
Finished: the 100%-vibe-coded "GPT-5 reviews all my PRs on max reasoning" GitHub app (which is shockingly effective, https://github.com/Smaug123/robocop - probably nothing new for people who already use some product like this, but I like owning my own infrastructure as far as possible, and GPT-5 and perhaps Gemini are the only models smart enough to do this so I can't take this any further).
Currently: back on "write an immediate-mode TUI framework that uses a vdom as its fundamental abstraction" (https://github.com/Smaug123/WoofWare.Zoomies), in the hope that this is the first UI framework that I don't absolutely loathe.
Next: using the TUI framework, write a debugger to inspect the internal state of my deterministic .NET runtime (https://github.com/Smaug123/WoofWare.PawPrint) and to step forwar
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d and backward in time.
Next: get the deterministic .NET runtime to a point where a property-based testing framework can identify the deadlock in some very simple buggy multithreaded code. (The framework is not yet able to run Hello World - did you know that's an incredibly complicated program in .NET? - but it can solve a few Advent of Code problems right now, can perform some limited exception handling, limited virtual method dispatch, limited casting between types. Even getting to Hello World might take a year if I'm unlucky.)
Ideas are coming way too fast to work on them all at the moment.
* Expect/snapshot testing library for F# is now seeing prod use but could do with more features: https://github.com/Smaug123/WoofWare.Expect
* A deterministic .NET runtime (https://github.com/Smaug123/WoofWare.PawPrint); been steaming towards `Console.WriteLine("Hello, world!")` for months, but good lord is that method complicated
* My F# source generators (https://github.com/Smaug123/WoofWare.Myriad) contain among other things a rather janky Swagger 2.0 REST client generator, but I'm currently writing a fully-compliant OpenAPI 3.0 version; it takes a .json file determining the spec, and outputs an `IMyApiClient` (or whatever) with one method per endpoint.
* Next-gen F# source generator framework (https://github.com/Smaug123/WoofWare.Whippet) is currently on the back burner;
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Myriad has more warts than I would like, and I think it's possible to write something much more powerful.