# \#rfc **URL:** https://discourse.julialang.org/tag/rfc/1186.md [Latest](https://discourse.julialang.org/latest.md) · [Categories](https://discourse.julialang.org/categories.md) · [Tags](https://discourse.julialang.org/tags.md) --- ## [RFC: Proposal for estimating unique Julia clients without tracking](https://discourse.julialang.org/t/rfc-proposal-for-estimating-unique-julia-clients-without-tracking/138027)

**Author:** [@StefanKarpinski](https://discourse.julialang.org/u/StefanKarpinski)\ **Replies:** 68\ **Last updated:** [September 3, 2026, 3:26am UTC](https://discourse.julialang.org/t/rfc-proposal-for-estimating-unique-julia-clients-without-tracking/138027 "2026-09-03T03:26:28Z")

I’ve written up a new protocol that would allow us to estimate how many unique Pkg clients there are for Julia and for each package in a way that doesn’t allow for tracking individual users. This works as a rough proxy f… --- ## [\`SparseArray\` types](https://discourse.julialang.org/t/sparsearray-types/138210)

**Author:** [@rokke](https://discourse.julialang.org/u/rokke)\ **Replies:** 5\ **Last updated:** [July 16, 2026, 6:56am UTC](https://discourse.julialang.org/t/sparsearray-types/138210 "2026-07-16T06:56:38Z")

SparseMatrixCSC currently has a documented type definition of: SparseMatrixCSC{Tv,Ti\<:Integer} \<: AbstractSparseMatrixCSC{Tv,Ti} but, if you try to actually make one, you will find in practice that it only has exactly … --- ## [Designing a Paths Julep](https://discourse.julialang.org/t/designing-a-paths-julep/124335)

**Author:** [@tecosaur](https://discourse.julialang.org/u/tecosaur)\ **Replies:** 198\ **Last updated:** [February 8, 2026, 4:36pm UTC](https://discourse.julialang.org/t/designing-a-paths-julep/124335 "2026-02-08T16:36:51Z")

Prompted by a gripe I made on Slack, thoughts I’ve had on paths have coalesed into the start of a Julep and a prototpye. At this stage, I’d love to get wider input on the idea and help shoring it up into a solid propo… --- ## [Pretty-printing small n-d arrays](https://discourse.julialang.org/t/pretty-printing-small-n-d-arrays/135200)

**Author:** [@rokke](https://discourse.julialang.org/u/rokke)\ **Replies:** 18\ **Last updated:** [January 28, 2026, 11:45pm UTC](https://discourse.julialang.org/t/pretty-printing-small-n-d-arrays/135200 "2026-01-28T23:45:53Z")

I haven’t really looked at anything yet; I figured this might be small enough to be a first contribution, but I first wanted to ask if it would be welcome before I spent a bunch of time on it. I really like the terminal… --- ## [Julep: Efficient Hierarchical Mutable Data](https://discourse.julialang.org/t/julep-efficient-hierarchical-mutable-data/125190)

**Author:** [@PatrickHaecker](https://discourse.julialang.org/u/PatrickHaecker)\ **Replies:** 47\ **Last updated:** [February 12, 2025, 4:54pm UTC](https://discourse.julialang.org/t/julep-efficient-hierarchical-mutable-data/125190 "2025-02-12T16:54:12Z")

TL;DR This proposal outlines a method to achieve space and time-efficient writable substructures in Julia. The memory layout is identical to that of immutable structs within mutable structs. This approach allows to expre… --- ## [Making \`setindex\` public, how to document it, rethinking the Collections docs](https://discourse.julialang.org/t/making-setindex-public-how-to-document-it-rethinking-the-collections-docs/117419)

**Author:** [@nsajko](https://discourse.julialang.org/u/nsajko)\ **Replies:** 13\ **Last updated:** [August 15, 2024, 12:03am UTC](https://discourse.julialang.org/t/making-setindex-public-how-to-document-it-rethinking-the-collections-docs/117419 "2024-08-15T00:03:06Z")

@aplavin is trying to make Base.setindex a public API of Julia, which seems like a good idea, given that many packages use it already and it seems like an OK interface. The question is, how to document it. The function i… --- ## [RFC: add a Type called AnyType that's subtyped by all other types except Any](https://discourse.julialang.org/t/rfc-add-a-type-called-anytype-thats-subtyped-by-all-other-types-except-any/93956)

**Author:** [@nsajko](https://discourse.julialang.org/u/nsajko)\ **Replies:** 20\ **Last updated:** [October 26, 2023, 11:38pm UTC](https://discourse.julialang.org/t/rfc-add-a-type-called-anytype-thats-subtyped-by-all-other-types-except-any/93956 "2023-10-26T23:38:58Z")

Add AnyType between Any and all other types Situation The discussions here on Discourse and on Github make it clear that there are disagreements and confusion within the Julia community (including both users and core mem… --- ## [\[RFC\] Kirstine.jl - Bayesian Optimal Design for Nonlinear Regression](https://discourse.julialang.org/t/rfc-kirstine-jl-bayesian-optimal-design-for-nonlinear-regression/103993)

**Author:** [@lsandig](https://discourse.julialang.org/u/lsandig)\ **Replies:** 0\ **Last updated:** [September 18, 2023, 3:50pm UTC](https://discourse.julialang.org/t/rfc-kirstine-jl-bayesian-optimal-design-for-nonlinear-regression/103993 "2023-09-18T15:50:46Z")

I wrote Kirstine.jl, a package for finding Bayesian optimal designs for nonlinear regression models, i.e. for answering the question “What proportion of measurements should I take at which covariate settings in order to … --- ## [\[RFC\] HotTest.jl - A tool to make running tests interactively more convenient](https://discourse.julialang.org/t/rfc-hottest-jl-a-tool-to-make-running-tests-interactively-more-convenient/89733)

**Author:** [@jules](https://discourse.julialang.org/u/jules)\ **Replies:** 0\ **Last updated:** [November 3, 2022, 8:00pm UTC](https://discourse.julialang.org/t/rfc-hottest-jl-a-tool-to-make-running-tests-interactively-more-convenient/89733 "2022-11-03T20:00:53Z")

I’ve just created a small new package called HotTest.jl which is supposed to make working with Julia’s default testing pipeline interactively a bit more convenient. Let me just copy the README text here, and I would be …