| March 1998 |  | Mike quits his job and begins developing Dr. Lunatic at home as a modern sequel to his 1993 SPISPOPD game. |
| July 1998 |  | Hamumu Software officially registered in San Luis Obispo, CA. |
| October 1998 | | Development begins on Eddie Galaxy for eGames (Finished, Dr. Lunatic is gathering dust). |
| December 1998 | | eGames likes Dr. Lunatic, sort of. So Spooky Castle is created for their bundles. Eddie Galaxy is also finished. |
| January 1999 | | Amazin' SPISPOPD is written. |
| February 1999 | | Production begins on Kid Mystic, again because eGames kinda liked Dr. Lunatic, but not quite. |
| March 1999 | | Eddie Galaxy is released by eGames. For this year and the next, many bundles with Spooky Castle on them are released. |
| August 1999 | | Kid Mystic is released by eGames. |
| July 1999 | | We release Amazin' SPISPOPD ourselves. Our first self-published game! |
| October 1999 | | Hamumu Software relocates to San Diego, CA. Work resumes on Dr. Lunatic, including creating the Expando-Pak. |
| May 2000 | | Dr. Lunatic and Expando-Pak are finally released! |
| June 2000 | | Work begins on SpaceBoy, which becomes Sol Hunt after a few months. |
| September 2000 | | Hamumu Software relocates to another part of San Diego. |
| October 2000 | | Loonyland is begun, with the plan of being a quick Halloween game... |
| March 2001 | | Loonyland is released, only 5 months later! |
| May 2001 | | Sol Hunt rests on the back burner, as Stockboy begins production. |
| July 2001 | | The Fun Pack for Dr. Lunatic is created to amuse Dr. L fans. |
| October 2001 | | Hamumu Software relocates yet again, to Temecula. We'll stay here for a while. |
| November 2001 | | Dr. Lunatic is distributed via Pay-Per-Use by Softfamily in Korea. |
| June 2002 | | Stockboy and XOP are both released! XOP is our first externally developed game. |
| October 2002 | | Pumpkin Pop is secretly developed and quickly released as a Halloween surprise! |
| August 2003 | | The website is totally overhauled, and we begin handling orders directly ourselves. |
| September 2003 | | Dr. Lunatic Supreme With Cheese is released. |
| October 2003 | | Development of Grimbelina (working title) is begun. |
| January 2004 | | Development of Grimbelina is viciously interrupted by development of yet another version of Sol Hunt. |
| May 2004 | | Spooky Castle is released as a freebie game. |
| May 2004 | | Loonyland is patched with new merit badges, characters, game modes, and areas, tons more gameplay added! |
| June 2004 | | Eddie Galaxy is re-released by Hamumu for direct sales! |
| July 2004 | | We release Dungeon Scroll, developed by Robinson Technologies. |
| August 2004 | | We release Derelict, developed by Laughing Dragon Games (with artwork by Hamumu!). |
| October 2004 | | Kid Mystic is re-released by Hamumu, with lots of major enhancements! |
| January 2005 | | Another attempt at Sol Hunt, this time in multiplayer form. |
| February 2005 | | Pumpkin Pop for the Macintosh is released, our first Mac offering. |
| May 2005 | | Work begins on Super Happy Go Go Ninja Time (sorry again, Sol!). |
| June 2005 | | Hamumu Software moves to Anza, California, out in the desert with dial-up internet. |
| July 2005 | | Another huge Supreme patch, adding new monster 'editing' features is here. |
| July 2005 | | Loonyland for the Macintosh is released at long last! |
| October 2005 | | Dumb: The Game is released. |
| December 2005 | | Loonyland 2 begins its long long production. |
| January 2006 | | Kid Mystic is released for the Mac. |
| December 2006 | | Loonyland 2 pre-orders are available. |
| February 2007 | | Loonyland 2: Winter Woods is released, and we upgrade to 'fabulous' satellite internet! |
| April 2007 | | Medusa's Lament is the result of Ludum Dare #9. |
| April 2007 | | Moon Invaders is released. |
| May 2007 | | Loonyland 2 Collector's Edition is released. |
| June 2007 | | Loonyland: Titan Tunnels is under development, as is a major website upgrade. |
| August 2007 | | XOP is no longer available for sale - you can get it free instead! |
| September 2007 | | Work secretly begins on Sleepless Hollow. |
| October 2007 | | The new website is released, with Dumb Accounts! |
| October 2007 | | Sleepless Hollow is released as a Halloween Surprise! |
| October 2007 | | The webgame Dumbwords is released. |
| November 2007 | | The webgame T.A.G. is released. |
| November 2007 | | Work begins on the next Adventure Of Bouapha. |
| December 2007 | | Ludum Dare 48-Hour contest #10 results in Short Fuse. |
| February 2008 | | Maze Of Ludicrosity webgame is released. |
| April 2008 | | Still Pond is released, like a leaf falling on shimmering water. |
| August 2008 | | Rise Of The Owls is released, a Ludum Dare #12 entry. |
| August 2008 | | Hamumu makes an appearance at the PAX conference in Seattle. |
| October 2008 | | Ninja Kitty vs. The Nukebots is the result of Mini-LD#4. |
| October 2008 | | Costume Party is released! A Halloween surprise! |
| December 2008 | | Costume Party Winter Pack is released. |
| January 2009 | | Costume Party Dumb Pack is released. |
| March 2009 | | Behind The Dumb begins, chronicling the development of Loonyland Tactics. |
| May 2009 | | A wee little hiatus in Behind The Dumb as the Hamumu website is massively overhauled. |
| October 2009 | | Costume Party Fantasy Pack is released! A Halloween surprise! |
| November 2009 |  | The Hamumu Clubhouse is born! |
