Intrepyd

Intrepyd is a python module that provides a simulator and model checkers in form of a rich API, to allow the rapid prototyping of formal methods algorithms for the rigorous analysis of circuits, specifications and models.

• Circuits of inputs, latches and combinational nets over booleans, bounded and unbounded integers, reals and floats.
• A simulator, and four engines: bounded model checking, k-induction, backward reachability and IC3/PDR, whose proofs are checked; a portfolio runs them all in parallel, and answers with the first of them.
• Front-ends for Lustre and IEC 61131-3 Structured Text (PLCopen XML).
• Traces as plain dictionaries, and CSV files.

pip install intrepyd

Wheels are available for Linux (x86-64, glibc 2.28 or newer), Windows (x86-64) and macOS (13.3 or newer, Apple silicon), for python 3.11 or newer. Each one carries the intrepid model checking library for its platform, so there is nothing else to install.

import intrepyd as ip
from intrepyd.engine import EngineResult

ctx = ip.Context()
int8_t = ctx.mk_int8_type()
c = ctx.mk_latch('c', int8_t)
ctx.set_latch_init_next(c, ctx.mk_number('0', int8_t),
                        ctx.mk_add(c, ctx.mk_number('1', int8_t)))

bmc = ctx.mk_bmc()
bmc.add_target(ctx.mk_eq(c, ctx.mk_number('5', int8_t)))
bmc.set_current_depth(5)
assert bmc.reach_targets() == EngineResult.REACHABLE

The documentation, the source and the issue tracker are on GitHub; a collection of experiences using Intrepyd is in the Formal Methods Little Corner.

Intrepyd is free for noncommercial purposes, such as personal use and use by universities and public research organizations, under the PolyForm Noncommercial License 1.0.0. Any other use, in particular by companies for a commercial purpose, requires a commercial license: write to license@intrepid-studio.eu. Versions up to 0.14.0 were released under the BSD 3-Clause license. The intrepid library bundled in the wheels is proprietary, and its license, installed as intrepyd/LICENSE.intrepid, allows it to be used and redistributed, unmodified, as part of intrepyd, within the same terms. It links the Z3 SMT solver, released under the MIT license. Its engines run once the end-user license agreement is accepted (python -m intrepyd.eula accept).