PVS vs TLA+
PVS
pvs.csl.sri.comTLA+
lamport.azurewebsites.netSide by side
| Figure | PVS | TLA+ |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Windows | Yes | Yes |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| Plans published | 2 | 1 |
| Spec score · Formal Verification Tools | 8.3 (#4) | 7.5 (#24) |
| Platforms | Current listed releases target 64-bit Linux and macOS; the site says Windows can run PVS 7.1 or later through Vagrant and VirtualBox. | The Toolbox download instructions cover Windows, Mac OS, and Linux. |
| Purpose | PVS is a verification system combining a specification language, support tools, and a theorem prover. | TLA+ is a high-level language for modeling software and hardware systems, especially concurrent and distributed systems. |
| Support | Support is offered through developer and bug-report email addresses, GitHub issues, Google Groups, and moderated mailing lists. | The TLA+ Foundation directs technical questions and issues to the appropriate GitHub issue tracker. |
Plans
In their own words
PVS
PVS is a mechanized environment for formal specification and verification, intended for work such as mathematical formalization and hardware or algorithm verification. Its language is based on typed higher-order logic and supports predicate subtypes, dependent types, and parameterized theories. The system combines predefined theories, a type checker, interactive theorem prover, symbolic model checker, utilities, libraries, documentation, and examples. Proof support includes induction, rewriting, simplification with decision procedures, abstraction, and symbolic model checking; command-line tools can re-prove theories and libraries in batch mode. PVS also integrates the Yices SMT solver, supports random testing during proofs, and includes PVSio for evaluation and animation. GNU or X Emacs provides the integrated interface, with Tcl/Tk displays for proof trees and theory hierarchies. It runs on Linux, macOS, and Windows and is self-hosted. Noncommercial use is listed at free. Sources are under GPL, but the Allegro runtime has a separate click-through license, and commercial users need a current PVS license or must contact SRI about licensing.
TLA+
TLA+ has no write-up on Specifiction yet; its figures are above.