Book |

Projects |

Talks |

Theses |

Papers |

Podcasts |

Blogs |

## What is miniKanren?

miniKanren is an embedded Domain Specific Language for logic programming.

The core miniKanren language is very simple, with only three logical operators and one interface operator.

The core language, using Scheme as the host language, is described in this short, interactive tutorial.

miniKanren has been implemented in a growing number of host languages, including Scheme, Racket, Clojure,

Haskell, Python, JavaScript, Scala, Ruby, OCaml, and PHP, among many other languages.

miniKanren is designed to be easily modified and extended; extensions include Constraint Logic Programming,

probabilistic logic programming, nominal logic programming, and tabling.

A detailed discussion of the differences between miniKanren and Prolog can be found here.

## The Book

Daniel P. Friedman,

William E. Byrd,

Oleg Kiselyov, and

Jason Hemann

*The Reasoned Schemer, Second Edition*

The MIT Press, Cambridge, MA, 2018

## miniKanren Online Uncourse (via Hangouts on Air)

Will Byrd organizes a weekly miniKanren uncourse, which meets Sundays at noon Pacific/3pm Eastern time. We show off miniKanren projects, talk about miniKanren implementation, and do live coding/live research. A link to each week’s hangout is posted to the

miniKanren uncourse mailing list.

Recordings of previous uncourse hangouts.

## Implementations

### Scheme

miniKanren-with-symbolic-constraints

miniKanren with extensions for symbolic constraint solving. Includes compatibility files for Racket and various Scheme implementations.

<!– miniKanren

–>

microKanren

A minimal miniKanren implementation, as described in the 2013 Scheme Workshop paper.

microKanren w/simple complete search

A modified/improved microKanren implementation, as described in the 2016 DLS paper.

alphaKanren

miniKanren extended with nominal logic programming, as described in the 2007 Scheme Workshop paper.

probKanren

Research prototype of miniKanren with probabilistic inference.

microKanren-sagittarius

miniKanren implementation for R7RS sagittarius scheme 0.6.0 based on (microKanren) with the `=/=`

operation added.

rKanren

miniKanren with guided search, as described in the 2013 Scheme Workshop paper.

bkanren

miniKanren with constraint extensions that runs under Bigloo Scheme.

Fork: bkanren

<!–

cKanren

miniKanren extended with Constraint Logic Programming (CLP), as

described in the 2011 Scheme Workshop paper.

–>

slpKanren

Stochastic Logic Programs (SLP) style probabilistic logic programming in miniKanren. (Deprecated–please see probKanren instead.)

sokuza-kanren

Oleg Kiselyov‘s minimal implementation of logic programming.

### Racket

miniKanren-with-symbolic-constraints

miniKanren with extensions for symbolic constraint solving. Includes compatibility files for Racket and various Scheme implementations.

cKanren

miniKanren extended with Constraint Logic Programming (CLP); an improved version of the

system described in the 2011 Scheme Workshop paper.

Racket-miniKanren

vanilla miniKanren Racket port

recursive miniKanren

recursive miniKanren implementation in Racket.

zKanren

cKanren with fair conjunction

### Clojure

core.logic

(

core.logic cheatsheet, courtesy of

Benjamin Peter)

A literate Clojure implementation of microKanren.

async-mu-kanren

Proof-of-concept implementation of muKanren using CSP (core.async)

### Assorted Languages

Implementations of microKanren in assorted languages

### C#

### CoffeeScript

### Common Lisp

Kanren-Fset (Fset collection library support for cl-kanren-trs)

### Dylan

### Elixir

### Elm

### Emacs Lisp

### Erlang

### Extempore

### F#

logic

A logic programming library for F#

MiniKanren

An attempted implementation of MiniKanren in F#.

### Go

### Groovy

### Haskell

### Hy

### Java

mk.java

microKanren in Java.

java8kanren

miniKanren in Java.

### JavaScript

veneer

Browser based miniKanren editor and REPL, with constraints.

microScopeKanren

A JavaScript implementation of microKanren with a focus on inspecting programs as they run.

Example, vizualizing `appendo`

mu-kanren

A step-by-step MicroKanren evaluator.

GitHub repo

### Lisp Flavored Erlang

### Lua

### Mímir experimental rules engine

### miniKanren

### ML

### Moxie

### Nu

### OCaml

OCanren

Statically typed embedding of miniKanren into Objective Caml.

### PHP

### Prolog

microkanren-prolog

A Prolog implementation of microKanren.

### Python

### Pure

### Ruby

### Rust

### Scala

kanren (Sokuza-kanren in Scala)

### Shen

### Smalltalk

Smalltalk Hub link to microkanren-pharo

## Projects using miniKanren or core.logic

### miniKanren

Barliman

Barliman is a prototype “smart editor” that performs real-time program synthesis to try to make the programmer’s life a little easier.

minimips

minikanren mips assembler/disassembler.

### core.logic

SMUG

The Sheet Music Generator.

expresso

A clojure library for symbolic manipulation of Algebraic Expressions.

tutorial

blog post

webdriver-logic

Logic programming API for testing web applications using clj-webdriver.

Clojure/conj 2012 talk

damp.ekeko

Ekeko enables querying and manipulating an Eclipse workspace using applicative logic programs.

anouncement

screencast

damp.qwal

QWAL is a path expression library to allow querying graphlike structures using core.logic in Clojure.

damp.qwalkeko

Scrape and reason over Java projects stored on git.

peano

Using logic programming (Clojure’s core.logic) for test data manipulation and generation.

kibit

kibit is a static code analyzer for Clojure which uses core.logic to

search for patterns of code for which there might exist a more

idiomatic function or macro.

parsing-packet-with-logic

A small experiment in parsing packets in a style similar to Erlang’s `<<...>>`

using core.logic.

maze.logic

Solving mazes using core.logic.

Janus: Consumer-driven Contracts and Mocks

Consumer-driven contracts using core.logic.

Monotony

Monotony is a solution to the problem of how to schedule things in a way that humans find intuitive.

QWAL

QWAL is a path expression library to allow querying graphlike structures using core.logic in Clojure.

FunnyQT

FunnyQT is a model querying and transformation library.

symbol

symbol is a compiler of a subset of Clojure syntax to C++.

guzheng

guzheng is a library for doing branch coverage analysis of Clojure code.

Adventure in Clojure core.logic

Text adventure game in core.logic.

The core.logic wiki also has links to projects using core.logic.

## Upcoming Talks

William E. Byrd (joint work with Michael Ballantyne, Gregory Rosenblatt, and Matthew Might)

A Unified Approach to Solving Seven Programming Problems (Functional Pearl)

International Conference on Functional Programming (ICFP), Oxford, England, 4 September 2017.

paper |

## Recorded Talks

### miniKanren

<!– not recorded, I believe

Jason Hemann and Daniel P. Friedman

A Framework for Extending microKanren with Constraints

Scheme Workshop, Vancouver, BC, Canada, 5 September 2015.

–>

Tom Stuart

Hello, declarative world

LRUG August 2015 Meetup, August 8, 2015.

Dan Friedman and Jason Hemann

How to be a good host: miniKanren as a case study

Curry On, Prague, Czech Republic, 7 July 2015.

William Byrd

The Promise of Relational Programming

PolyConf 15, Poznań, Poland, 2 July 2015.

Bodil Stokke

μKanren: Running the Little Things Backwards

EuroClojure, Barcelona, Spain, 25 June 2015.

Daniel Brady

Little Logic Languages

Scheme Workshop, Washington, D.C., 19 November 2014.

Jason Hemann and Dan Friedman

Write the Other Half of Your Program: From Functional to Logic Programming

Strange Loop, St. Louis, September 18, 2014.

<!–

William E. Byrd and Daniel P. Friedman

Program Synthesis Using miniKanren

Strange Loop, St. Louis, September 17, 2014.

–>

William E. Byrd

Relational Programming in miniKanren, Part 1 and Part 2

Logic Night

Lambda Lounge Utah, Sandy, UT, May 13, 2014.

<!–

Jason Hemann and Dan Friedman

Roll Your Own Relational DSL: A Logic Programming Language in Less than 40 Lines

Lambda Jam, Chicago, July 22, 2014.

–>

<!–

William E. Byrd and Nada Amin

Meta-Programming in Logic Programming

Code Mesh 2013, London, England, December 5, 2013.

–>

Daniel P. Friedman and William E. Byrd

A Relational Exploration of the Chomsky Hierarchy

Strange Loop, St. Louis, September, 2013.

William E. Byrd and Daniel P. Friedman

Fun with Relational Interpreters in miniKanren

flatmap 2013, Oslo, Norway, May 14, 2013 (keynote).

William E. Byrd and Daniel P. Friedman

miniKanren Philosophy

Clojure/conj 2012, Raleigh, NC, November 16, 2012.

(Beware the pink tint!)

Daniel P. Friedman and William E. Byrd

Relational Programming in miniKanren

Strange Loop 2012, St. Louis, MO, September 24, 2012

source code

Daniel P. Friedman and William E. Byrd

miniKanren “untalk”

Clojure/conj 2011, Raleigh, NC, November 10, 2011.

### core.logic

From Greek to Clojure

Clojure/conj, Alexandria, VA, November 14, 2013

Craig Brozefsky

Core.logic and SQL Killed my ORM

Clojure/West 2013, Portland, OR, March 19th, 2013.

David Nolen

The Refined Clojurist

Clojure Exchange 2012, London, December 6, 2012

Daniel Gregoire

Web Testing with Logic Programming

Clojure/conj 2012, Raleigh, NC, November 17, 2012.

webdriver-logic project

Steve Miner

Challenges for Logic Programming

Clojure/conj 2012, Raleigh, NC, November 17, 2012.

Edmund Jackson

An Introduction to Logic Programming on the JVM with core.logic (Clojure)

FP Days 2012, Cambridge, October 25, 2012

David Nolen

core.logic: A tutorial reconstruction (“unsession”)

Strange Loop 2012, St. Louis, MO, September 24, 2012

Edmund Jackson

core.logic.intro

EuroClojure 2012, London, May 24, 2012

source code

Ryan Senior

Practical core.logic

Clojure/West 2012, San Jose, March 17, 2012

Ambrose Bonnaire-Sergeant

Introduction to Logic Programming with Clojure

Clojure/conj 2011, Raleigh, NC, November 10, 2011.

### ClojureScript & core.logic

Constraint programming in the browser

(Talk focuses on the Cassowary constraint solver for GUI layout, but also discusses core.logic.)

JSConf US, Amelia Island, FL, May 31, 2013

### Clojure/West miniKanren confo, Portland, OR, March 19, 2013 (associated with Clojure/West)

Logic programming in the wild (video not posted yet)

Ryan Senior

Intro to CLP with core.logic

Adam Foltzer

Molog: Typed Functional Logic Programming in Haskell

source code

David Nolen

The Architecture of core.logic

Nada Amin

core.logic.nominal (video not posted yet)

source code

William E. Byrd and Daniel P. Friedman

The Unreasonable Schemers (video not posted yet)

source code

## Interviews

William Byrd on Logic and Relational Programming, miniKanren

Recorded by

InfoQ at Code Mesh 2013, London, England, December, 2013

## Written Tutorials

### core.logic

Introduction to Logic Programming with Clojure

Logic Programming for the Social Web

## Theses

### PhD

William E. Byrd

Relational Programming in miniKanren: Techniques, Applications, and Implementations.

Indiana University, Bloomington, IN,

September 30, 2009.

Easier to read, single-spaced, re-typeset version of Will’s dissertation, released under Creative Commons Attribution 4.0 International (CC BY 4.0) license.

### Masters

Wheeler, Kaylen FJ

Representing Game Dialogue as Expressions in First-Order Logic

University of Western Ontario, London, Ontario, Canada, 2013.

### Undergraduate

Ramana Kumar

Mechanising Aspects of miniKanren in HOL

Australian National University, Canberra, Australian Capital Territory, Australia,

May 2010. (Undergraduate Honors Thesis)

Emily Fox

Automated Canon Composition

Churchill College, University of Cambridge, Cambridge, UK,

May 10, 2016. (Computer Science Tripos – Part II)

## Papers

William E. Byrd, Michael Ballantyne, Gregory Rosenblatt, and Matthew Might

A Unified Approach to Solving Seven Programming Problems (Functional Pearl)

In Proceedings of the ACM on Programming Languages (PACMPL), 1, ICFP, Article 8 (August 2017), 26 pages.

DOI.

Interactive version of the paper, created by

Nada Amin.

Jason Hemann, Daniel P. Friedman, William E. Byrd, and Matthew Might

A Small Embedding of Logic Programming with a Simple Complete Search

In Proceedings of the 12th Symposium on Dynamic Languages (DLS 2016), Amsterdam, Netherlands, 2016.

Jason Hemann and Daniel P. Friedman

A Framework for Extending microKanren with Constraints

In Proceedings of the 2015 Workshop on Scheme and Functional Programming (Scheme ’15), Vancouver, British Columbia, 2015.

Daniel Brady, Jason Hemann and Daniel P. Friedman

Little Languages for Relational Programming.

In Proceedings of the 2014 Workshop on Scheme and Functional Programming (Scheme ’14), Washington, DC, 2014.

Complete source code (Scheme)

Erik Wennstrom

Tableau-Based Model Generation for Relational Syllogistic Logics.

In Proceedings of the 2014 International Symposium on Artificial Intelligence and Mathematics (ISAIM 2014), Fort Lauderdale, FL, January, 2014.

Jason Hemann and Daniel P. Friedman.

microKanren: A Minimal Functional Core for Relational Programming.

In Proceedings of the 2013 Workshop on Scheme and Functional Programming (Scheme ’13), Alexandria, VA, 2013.

Complete source code (Scheme)

Cameron Swords and Daniel P. Friedman.

rKanren: Guided Search in miniKanren.

In Proceedings of the 2013 Workshop on Scheme and Functional Programming (Scheme ’13), Alexandria, VA, 2013.

Complete source code (Scheme)

William E. Byrd, Eric Holk, and Daniel P. Friedman.

miniKanren, Live and Untagged: Quine Generation via Relational Interpreters (Programming Pearl).

To appear in the Proceedings of the 2012 Workshop on Scheme and Functional Programming, Copenhagen, Denmark, 2012.

Complete source code (Scheme)

Claire E. Alvis, Jeremiah J. Willcock, Kyle M. Carter, William E. Byrd, and Daniel P. Friedman.

cKanren: miniKanren with Constraints.

In Proceedings of the 2011 Workshop on Scheme and Functional Programming (Scheme ’11), Portland, OR, 2011.

Complete source code (R6RS Scheme)

Ramana Kumar and Michael Norrish

(Nominal) unification by recursive descent with triangular substitutions

In Proceedings of the First international conference on Interactive Theorem Proving (ITP’10),

Springer-Verlag Berlin, pp. 51-66, 2010.

Andrew W. Keep, Michael D. Adams, Lindsey Kuper, William E. Byrd, and Daniel P. Friedman.

A Pattern-matcher for miniKanren -or- How to Get into Trouble with CPS Macros.

In Proceedings of the 2009 Workshop on Scheme and Functional Programming,

Cal Poly Technical Report CPSLO-CSC-09-03, pp. 37-45, 2009.

Joseph P. Near, William E. Byrd and Daniel P. Friedman.

alphaleanTAP: A Declarative Theorem Prover for First-Order Classical Logic.

In Proceedings of the 24th International Conference on Logic Programming (ICLP 2008),

LNCS vol. 5366, Springer-Verlag, Heidelberg, pp. 238-252, 2008.

Complete source code–R6RS Scheme and Prolog (.zip file)

Oleg Kiselyov, William E. Byrd, Daniel P. Friedman and Chung-chieh Shan

Pure, declarative, and constructive arithmetic relations (declarative pearl).

In Proceedings of the 9th International Symposium on Functional and Logic Programming,

ed. Jacques Garrigue and Manuel Hermenegildo, pp. 64-80.

LNCS vol. 4989, Springer, 2008.

William E. Byrd and Daniel P. Friedman

alphaKanren: A Fresh Name in Nominal Logic Programming.

In Proceedings of the 2007 Workshop on Scheme and Functional Programming,

Universite Laval Technical Report DIUL-RT-0701, pp. 79-90.

Authors’ revised version (recommended)

Revised source code (R5RS Scheme)

William E. Byrd and Daniel P. Friedman

From Variadic Functions to Variadic Relations: A miniKanren Perspective.

In Proceedings of the 2006 Scheme and Functional Programming Workshop,

University of Chicago Technical Report TR-2006-06, 2006, pp. 105-117.

Oleg Kiselyov, Chung-chieh Shan, Daniel P. Friedman, and Amr Sabry

Backtracking, interleaving, and terminating monad transformers: (functional pearl).

In Proceedings of the 10th ACM SIGPLAN International Conference on Functional Programming (ICFP ’05),

ACM Press, New York, pp. 192-203, 2005.

## Screencasts

### Thomas G. Kristensen

Composing music using core.logic and Overtone – The Composing Schemer

blog post

source code

January 2013.

### Timothy Baldridge

Clojure Core.Logic With Custom Data Sources

October 25, 2013.

Bytecode Assembler in Core.Logic

related blog post

Dec 13, 2012.

### Coen De Roover

Getting started querying an Eclipse workspace using Ekeko

ekeko project

August 14, 2012.

## Weekly Google Hangout on Air

### Upcoming Hangouts

### Previous Hangouts

Hangout #13, Sunday, June 30.

Topic: Claire shows off a new macro for defining constraints using attributed variables, a new version of the matche pattern matching macro, and the implementation of templateo (declarative

`copy_term`

) (

URL). Norman demos his

code for solving

nonogrids problems. Will talks about CPSing miniKanren programs.

Hangout #12, Sunday, June 23, 2013.

Topic: Gary shows off his CLP(FD) program to layout 2D figures; Will describes the new, apparently fixed `templateo`

constraint, and explains how it is used in a relational term reducer for the untyped lambda-calculus.

Hangout #11, Sunday, June 9, 2013.

Topic: Unexpected memory usage in `conde`

, and how to fix it in CLP(FD); meta-interpreters in miniKanren (code); what do you need to know to use miniKanren effectively?; Will’s new book on miniKanren (in progress).

Hangout #10, Sunday, June 2, 2013.

Topic: We discuss CLP(Set) and declarative `copy_term`

(a.k.a., `templateo`

) (code). Lindsey shows off LVish (code). David poses a core.logic puzzle. Dan and Jason discuss miniC, a minimal miniKanren without macros. Will shows off a relational lambda calculus reducer (code).

Hangout #9, Sunday, May 19, 2013.

Topic: Will shows off a meta-circular interpreter for miniKanren (code), and describes the outline for a new book he is writing on relational programming (book).

Hangout #8, Sunday, May 5, 2013.

Topic: Dan and Jason show off a cool way to implement mutual recursion in an interpreter. Will and the gang then live-code a relational interpreter for general Deterministic Finite Automata (code).

Hangout #7, Sunday, April 28, 2013.

Topic: Translating simple Scheme functions to miniKanren using correctness-preserving transformations.

Hangout #6, Sunday, April 21, 2013.

Topic: Live coding/real-time solution of a simple problem solved by Michael. Also, Claire discusses new features of cKanren in Racket.

Hangout #5, Sunday, April 14, 2013.

Topic: Stump the Chump! Will partially translates miniKanren’s unify function from Scheme into miniKanren (code). Also, discussion of extra-logical operators, and new miniKanren features in progress: CLP(Set), constraint handling rules, lazy constraints for recursion.

Hangout #4, Sunday, April 7, 2013.

Topic: Debugging miniKanren programs; Constraint Logic Programming over sets (based on the paper Sets and Constraint Logic Programming by Dovier, et al., 2000).

Hangout #3, Sunday, March 31, 2013.

Implementation of simplified miniKanren (source code).

Hangout #2, March 24, 2013.

Implementing disequality constraints, absento/presento constraints, miniKanren Confo at Clojure/West, relational CESK machine.

Hangout #1, March 10, 2013.

A little miniKanren history, what it means to be relational, a relational variant of copy-term, debugging miniKanren programs.

## Podcasts

Mostly lazy… a Clojure podcast

Episode 9 with Kevin Lynagh and Paul deGrandis: web dev ennui, CRDTs, and core.logic

Recorded December 14th, 2012.

## Blogs

### David Nolen – dosync

Logic Programming is Underrated

The Simply Typed Lambda Calculus in 20 Lines Redux

From David Nolen’s old blog (courtesy of the Internet Archive’s Wayback Machine):

Know Your Bounds

friendlier

sudoku

A Logic Programming Reading List

Logic Programming & JavaScript

core.logic & VPRI STEPS

Another Taste of cKanren

A Taste of cKanren

Simple Type Inference For The Simply Typed Lambda Calculus in ~20 Lines

Logos -> core.logic

Crazy Ideas

Fun

Spring Cleaning

Simple Constraints

~2.1ms

Tabling in Logos

Pattern Matching

Finally … a clue

Performance Matters

Faster Unification

Logic Programming and Performance

A Short Break

Life Without Tail Call Optimization

Announcing Logos

A miniKanren introduction via Clojure

### Nick Drozd

Generating Sentences of Modal Logic

Generating Propositional Logic Proofs

### Clojure & lx

Another Logic Programming Reading List

lx in core.logic #3: Finite State Transducers

lx in core.logic #2: Jumps, Flexible Transitions and Parsing

Finite State Machines in core.logic

### Oskar Wickström

Generating Sight-Reading Exercises using Constraint Logic Programming in Clojure, Part 1

### Timothy Baldridge – (apply clojure @life)

Bytecode Assembler in Core.Logic

### Thomas G. Kristensen – Clojure/tgk

Parsing packets Erlang style using core.logic

Finding cliques in graphs using core.logic

Maximum cliques algorithm in Clojure

### Edmund Jackson – boss level

mini-Sudoku in mini-Kanren (in Clojure-“ish”)

Logic Programming Part 3 (List Logic)

Logic Programming Part 2 (Building Blocks)

### clojure.com – Clojure/core (posts by Stuart Sierra)

### Jim Duey – A Clojure Story

### Christophe Grand – Clojure and me

Fair conjunction: status report

### Ryan Senior – Object Commando

The Magical Island of Kanren – core.logic Intro Part 1

### Martin Trojer

Replicating Datomic/Datalog queries with core.logic, take 2

Replicating Datomic/Datalog queries with core.logic, take 1

N-Queens with core.logic, take 2

N-Queens with core.logic, take 1

### Atomic Object – Atomic Spin

The First Time Programming Scared Me

### Kris Jenkins

Solving Logic Puzzles With Clojure’s Core Logic, Part Two

Solving Logic Puzzles With Clojure’s Core Logic, Part One

### Brian Taylor

PPfAI Chapter 2 (in Clojure Core.Logic)

PPfAI Chapter 1 in Clojure Core.Logic

### Paul Callaghan – PragPub Magazine

Unification: It’s Not Just for Prolog

### Lindsey Kuper

Generating tautologies with miniKanren

### Michael R. Bernstein

A Nice Feature in core.logic and Thoughts About A Data Structure

### Julia Evans

Day 31: Binary trees with core.logic!

### Maria Pacana

### Meikel Brandmeyer

A field trip into logic programming

### Tassilo Horn

Using Clojure’s core.logic with custom data structures

### Cameron Swords

rKanren: Guided Search in miniKanren, Part 1

### Tim Yates

Using Clojure and core.logic from Groovy

### Peteris Erins

Temporal logic programming in Clojure core.logic

### Malcolm Sparks

Transitive relations in core.logic

### Alexander Zolotko

Getting my feet wet with Clojure’s core.logic

### Jamie Brandon

### Sam Neubardt – coderwall

Find Elements in a Collection Using core.logic

### JR Heard

Explorations in Clojure’s core.logic

### Oleg Prophet

Fun with Lambda calculus Interpreters in miniKanren

## Contact

This site is maintained by Will Byrd:

webyrd@gmail.com.

Thanks to Shantanu Kumar, Martin Trojer, and Gergely Nagy for improving the site by submitting a pull request.