Software Engineering Daily

Building Games at Zachtronics with Zach Barth (Dec 18, 2025)

Episode Overview

This episode features Zach Barth, founder of Zachtronics and now Coincidence Games, in conversation with developer and educator Joe Nash. The discussion traces Zach’s unconventional path through game development, delves into the philosophy and technical underpinnings of iconic “Zach-like” puzzle games, the process of founding and running indie studios, and the release and design philosophy behind their latest game, Kaizen. Other topics include the unique business and technical structures that enable their distinctively creative output, the evolution of puzzle game mechanics conducive to both learning and optimization, and reflections on community engagement amid changing industry and social media landscapes.

Key Discussion Points & Insights

1. Defining the “Zach-like” Genre [01:41–03:29]

• Open-ended, engineering puzzle games: Zachtronics titles give players a defined outcome and a set of tools, but enormous freedom in solution, often mirroring the problem-solving experience of programming or engineering.

  • “You can write any code you want as long as it solves the problem and meets the spec… but they all take the form of open-ended programming problems with a huge number of solutions.” — Zach [02:14]
  • Games include optimization “secondary metrics” familiar to programmers, akin to leaderboards or Leetcode.

• Origin of the term ‘Zach-like’: Zach disavows ever having coined it (and finds it a little uncomfortable), but acknowledges it as a recognizably distinct design philosophy.

2. Early Career and Entry to Games [04:01–11:15]

• Unconventional journey:
  • Game studio internship post-college focused on “bland” contracting work (e.g., military projects, DLC packs), sparking his realization that he preferred design over professional programming.
  • At Microsoft, worked on Visio (diagramming software): “It looks like a drawing product, but behind the scenes it's a spreadsheet... a lovely product for someone into user interfaces and design.” — Zach [07:38]
  • Moonlighted as indie dev, releasing Flash and downloadable puzzle games, eventually leading to SpaceChem and the full-time founding of Zachtronics.

3. Microsoft, Valve, and the Indie Leap [11:18–24:38]

• Leaving corporate for indie:

  • After success with SpaceChem, Zach and collaborators went full-time indie with Zachtronics.
    • “By the time I managed to switch to the games team, I'd already gathered kind of a large group of fans for just a random person making free games.” — Zach [09:57]
  • Brief stint at Valve working on VR (“The Lab,” Zortex 26XX mini-game), characterized by creative frustration within a flat, highly autonomous but sometimes inert structure.

• Themes of burnout and iterative risk: Repeated cycles of creative excitement, financial anxiety, burnout, and reinvention.

4. Business Structure & Studio Evolution [24:38–34:15]

• Lifecycle of Zachtronics:

  • Sold to Alliance to achieve financial stability (“We were always one game away from going out of business…it made me do stupid things like ‘we have to make a game that'll make a lot of money’…not helpful for creativity.” — Zach [24:39]), enabling a prolific run of titles (Opus Magnum, Exapunks, etc.).
  • Changing fortunes (e.g., Toys R Us collapse impacting publisher) led to further instability and eventual decision to “wrap up” the studio.

• Birth of Coincidence Games:

  • Established as a co-op, contract-based structure: “Everybody just gets paid with what they work on...no salaries, keep a ledger.” [32:04]
  • Not common in games, but “Seems normal to a programmer; weird to games people.”

• Remote work skepticism: Zach finds remote-only companies too isolating and conflict-prone; Coincidence prioritizes in-person collaboration.

5. Kaizen: Design, Reception, and Philosophy [37:22–44:08]

• Project overview: Kaizen is a factory-themed puzzle game set in 1980s Japan, combining accessible mechanics with the optimization challenges Zachtronics is known for.

• Mandate for approachability: Under publisher Astralogical’s direction, Kaizen was designed as the most accessible Zach-like yet.

  • “We made a game that’s kind of an introduction to those games…a tutorial for all the other Zachtronics games.” — Zach [39:19]
  • This led to some negative feedback from hardcore fans: “It only took five hours to beat. It just was getting good, and it ended.” — Zach quoting Notch [39:06]

• Design simplifications:

  • Removed or streamlined complex mechanics (e.g., spatial pipelines/tessellation of Opus Magnum) for clarity.
  • Introduced features like timeline scrubbing for troubleshooting, making iteration easier.

• Integration of story and aesthetics:

  • Heavily research-based visuals and voice acted cut-scenes to evoke time and place (1980s Japanese factories).
  • “It’s a little bit like a fake travel log... like going on vacation back in time.” — Zach [61:29]
  • Publisher influence toward a “cozy” and educationally safe theme.

6. Metrics, Community, and the Social Web [44:22–51:31]

• Leaderboards & Optimization Metrics:

  • Originated with early Flash games (e.g., Codex of Alchemical Engineering): leaderboards for speed/size, histograms instead of top-100 to discourage toxic competition or cheating, and easy solution sharing for collaborative optimization.
  • “Our games are open-ended, so you can optimize any metric. We make that part of the gameplay.” — Zach [44:43]
  • Evolving attitudes: optimization once drove intense engagement; less visible now, possibly due to social media fragmentation.

• GIF export for solution sharing: Exporting animated solution GIFs was “game-changing” for Opus Magnum’s virality on Twitter/Reddit. Kaizen’s more literal visuals have been less shareable.

7. Technical Foundations & Evolution [62:28–72:51]

• From XNA to homegrown engines—no Unity:

  • Early reliance on XNA, then SDL-based, then hand-built scene-graph and immediate-mode graphics/tooling.
  • Disenchantment with Unity: “Unity makes it easy to start projects and hard to finish them… performance was abysmal.” — Zach [69:07]
  • Preference for in-house C#-based engine: improves clarity, instant build/test, keeps teams small and nimble.
    • “We just copy the last project and delete all the game code out of it!”

• Why not 3D? Focus remains on 2D and pseudo-3D; 3D requires costly art and more complex engines, not aligned with their style of gameplay.

8. Rebranding and Audience Retention [73:09–75:49]

• Impact of shifting from Zachtronics to Coincidence:
  • Many players don’t track indie devs by studio, only by viral hits—so impact is small among casual players, but some “core” fans remain uninformed despite mailing lists and announcements.
  • “I still get emails saying, ‘I hope you make another game one day’—and I’m like, we did! It’s out now!” — Zach

9. Creative Process & What’s Next [76:06–83:19]

• On new projects:

  • The desire to blend systems-based gameplay with new forms (“models of computation,” “systems about stuff that grows”).
  • Importance of creative expression over aligning with market trends (“should we add more popular mechanics, or double-down on what we do best?”).
  • Teasers: Upcoming projects are described as “smaller, rougher, and experimental,” echoing the spirit of Last Call BBS and tapping into novel computational paradigms.

• Approach to magic and technology in games:

  • Zach’s “holy grail”: building internally coherent, fictional systems with the “verisimilitude of a real system.”
    • “I want to make a game about an engineering system that’s entirely fictional—but systematically functions as if it was real and coherent. That’s always the dream.” [82:59]

10. Community, Newsletters, and Tooling [83:30–87:58]

• Best way to follow Coincidence: Email newsletter prioritized over social (signal, not noise; infrequent and meaningful).
  • “I only send out emails when there's something exciting going on… Email is the best way to find out about stuff.” — Zach [83:30]
• On team tooling: Preference for simple Git-based version control (“we're a small team; our binaries aren’t that huge”), skepticism about over-engineered infrastructure; advice: focus on what works.

Notable Quotes & Memorable Moments

• On creative strengths and the Zach-like identity:
  • “My weaknesses in other contexts became my strength. I can walk the line and design games about programming. Arguably some of the best in class games about programming.” — Zach [06:34]
• On design vs. programming:
  • “The thing I really like is design—game design, product design.” — Zach [06:30]
• On making approachable games:
  • “I think we succeeded at actually making a game that's a tutorial for all the other Zachtronics games.” — Zach [39:19]
• On the danger of focusing on commercial hits:
  • “Every time I've tried to make a game that’s genuinely successful, it's been ineffective. I can't just be a different person and make something wildly successful.” — Zach [14:52]
• On social media community:
  • “GIF export blew up Twitter… Just blew up.” — Zach [51:10]
• On future ambitions:
  • “I want to make a game about an engineering system that’s entirely fictional—but systematically functions as if it was real and coherent.” — Zach [82:59]

Timeline of Important Segments

| Timestamp | Segment | | ---------- | ------------------------------------------------------------ | | 01:41 | Defining “Zach-like” games, genre origin | | 04:01 | Early game industry career experiences | | 09:55 | Indie game development & SpaceChem’s breakout | | 11:24 | Leaving Microsoft; Valve VR stint | | 24:38 | Selling Zachtronics; shifting to publisher-backed structure | | 32:04 | Founding Coincidence Games; cooperative structure | | 37:22 | Kaizen: concept, design values, critical reception | | 44:22 | Metrics, optimization, and the evolution of community | | 62:28 | Technical stack, from XNA to in-house engine | | 73:09 | Audience retention post-rebrand | | 76:06 | Future games, creative priorities | | 83:30 | Newsletters and community communication | | 86:08 | Version control and game team workflows |

Recap for New Listeners

This episode provides both newcomers and Zachtronics veterans with a candid, sharply insightful portrait of indie game development on the edges of software engineering, puzzle design, business structure, and creative philosophy. Whether you’re a fan of open-ended optimization puzzles, legacy software, or just want a peek at the processes behind one of indie gaming’s most unique studios, Zach Barth’s stories and reflections offer both practical lessons for engineers and inspiration for creators.