Mir JIT compiler library
Ranked 6 of 6 JIT compilers by recommenders
Fast code generation and a complete toolkit for building custom JIT compilers, but Canonical retired its display server, and critics call it a costly, limited detour.
Fast code generation and a complete toolkit for building custom JIT compilers, but Canonical retired its display server, and critics call it a costly, limited detour.
16 people gave an opinion
- recommend it
- 6
- criticize it
- 10
- approval share
- 38%
Recommended in 6 of 13 months
- November 2025: recommended
- December 2025: not recommended
- January 2026: not recommended
- February 2026: recommended
- March 2026: recommended
- April 2026: recommended
- May 2026: not recommended
- June 2026: recommended
- July 2026: not recommended
- August 2026: recommended
- September 2026: not recommended
- October 2026: not recommended
- November 2026: not recommended (month in progress)
Why it doesn’t carry the badge
- 6 people recommend itNeeds 10 or more, not met.
- 0.6 recommenders for every criticNeeds 2 to 1 or better, not met.
- Recommended in 6 of 13 monthsNeeds 4 or more, met.
The same three rules apply to every product, and the badge can’t be bought. How the badge works
What people say about it
The reasons people give, with the number of comments that give each one. Open a reason to read what they said.
Why people recommend it
Each mark is one comment
Tools for building custom JIT compilers
“There are JIT frameworks out there with much faster code-generation than LLVM: Cranelift, GNU Lightning, Mir.”
Comment from 23 Aug 2026 in “JIT Compiling Code in 5μs” “It has all the tools for custom JIT including a nice C compiler.”
Comment from 28 Apr 2026 in “C, Just In Time!”
What people warn about
Each mark is one comment
Abandoned by Canonical after years
“Mir and Unity were perfectly fine technologies but they retired it because they didn't want to see things through”
Comment from 25 Nov 2025 in “APT Rust requirement raises questions” “attempted to uproot for no purpose other than Canonical wanted more control”
Comment from 10 Apr 2026 in “What is RISC-V and why it matters to Canonical” “they figured out it was a really bad idea in time”
Comment from 4 Dec 2025 in “Valve reveals it’s the architect behind a push to bring Windows games to Arm” Costly distraction for Ubuntu
“Nobody picked Ubuntu because of Mir, or Compiz, or Upstart”
Comment from 21 Mar 2026 in “Ubuntu 26.04 Ends 46 Years of Silent sudo Passwords” “the financial burden of Ubuntu Mobile, Unity 8, and Mir”
Comment from 10 Oct 2026 in “Apple/macOS removed from official Unix registry” Many limitations, hard to use
“I see you ran into many of the same MIR issues and limitations I did.”
Comment from 4 Aug 2026 in “Solod: Go can be a better C” “Neither of MIR or IR are friendly/easy though.”
Comment from 3 Jun 2026 in “QBE – Compiler Back end: Version 1.3” Ubuntu-specific design, not standard
“it also insists on doing a lot of its own thing like using Mir instead of X and click packages.”
Comment from 25 Jan 2026 in “Google confirms 'high-friction' sideloading flow is coming to Android” “Or when they created Mir to replace X.”
Comment from 25 Mar 2026 in “Ubuntu wants to strip some of GRUB features in 26.10 for security purposes”
Other JIT compilers people recommend
The four most recommended other JIT compilers, with the same counts for each, so you can compare like for like. The tick on each bar marks the 2 to 1 line the badge needs.
| Product | Recommend | Criticize | Approval | Months | Owned | Badge |
|---|---|---|---|---|---|---|
| Numba | 30 | 9 | 77% | 9 | — | Approved |
| CPython experimental JIT | 13 | 16 | 45% | 3 | — | — |
| YJIT | 10 | 2 | 83% | 6 | — | Approved |
| HotSpot JVM | 8 | 0 | 100% | 4 | — | — |
| Mir JIT compiler libraryThis page | 6 | 10 | 38% | 6 | — | — |
What people said
13 of the 16 comments that mention it, newest first. Each links to the original comment.
“the financial burden of Ubuntu Mobile, Unity 8, and Mir”
“There are JIT frameworks out there with much faster code-generation than LLVM: Cranelift, GNU Lightning, Mir.”
“I see you ran into many of the same MIR issues and limitations I did.”
“Neither of MIR or IR are friendly/easy though.”
“It has all the tools for custom JIT including a nice C compiler.”
“attempted to uproot for no purpose other than Canonical wanted more control”
“Or when they created Mir to replace X.”
“Nobody picked Ubuntu because of Mir, or Compiz, or Upstart”
“I wish it stayed in the running.”
“come with nice technical descriptions”
“it also insists on doing a lot of its own thing like using Mir instead of X and click packages.”
“they figured out it was a really bad idea in time”
“Mir and Unity were perfectly fine technologies but they retired it because they didn't want to see things through”
Counts come from 1,795,640 Hacker News comments, November 2025 to November 2026. How we count. Report a mistake.