A C compiler in LISP, a LISP in C, and the subject that changed my life
In 1986 I took Compiler Techniques under Bruce Ellis and wrote a C compiler in LISP. I have got it running again, on hardware that did not exist when I wrote it.
I’m Chris Tham, an outrageous actualiser based in Sydney. I’m the founder of Hello Tham, a boutique strategy consulting company.
I am interested in short to medium term consulting opportunities relating to strategic business change, new/revised business/operating models, business process improvement, technology strategy/architecture and technology solutions.
My career has now spanned four decades and I am looking forward to entering the fifth:
Email me at chris@christham.net or call me at +61 413 008 577.
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In 1986 I took Compiler Techniques under Bruce Ellis and wrote a C compiler in LISP. I have got it running again, on hardware that did not exist when I wrote it.
What it took to recover my own conference papers from Word 2.0 and PowerPoint 4.0, and what it taught me about who is actually keeping my archive readable.
The template this site runs on, and what I learnt rebuilding it with two AI platforms.
I have written a book about working with AI well. It is free to read, and it argues that the model you pick matters far less than the work you do around it.
I have rebuilt thirty-five HP calculators, from the 1972 HP-35 to the HP Prime, as a single web app. Not an emulator, but a reimplementation in TypeScript.
The 1980 game Rogue and the expert system built to play it, both compiled to WebAssembly and running side by side in a browser tab. The original C, not a rewrite.
Colossal Cave Adventure ported to strictly typed TypeScript over a few breakfasts, and checked against the original's own ninety-five test transcripts. Then a second model laid out the cave map the first one could not.
A beautiful operating system, still healthy after 50 years.
There is no shame in retiring early, and potentially many benefits.
Advice on how to have a satisfying career and life
We picked a global process taxonomy off the shelf, could not make our own work fit inside it, and were eventually asked to write one of its sections ourselves.
A drum and bugle corps recorded so far below normal level that it needs the volume control at 11:30 — and then becomes the most startling demonstration disc I have heard.
The first SACD released by an Australian independent artist: new age piano produced by Will Ackerman and mastered by Bob Ludwig, in a mix I wanted to be bolder.
Solo piano readings of Mitchell, Sting, Marley, Young and Dylan that take their time letting you work out which song you are hearing. Audition before buying.
A trio with a Hammond B-3 where the acoustic bass should be, playing original mid-tempo numbers and ballads. Almost an hour long, and I wanted more.
ECM-ish contemporary jazz coloured by oud and Middle Eastern lines, with Gary Peacock and Paul Motian completing the trio, in an enveloping 5.0 mix.
A whole disc of works for clarinets and strings, vibrantly played and miked closely enough that the breathing and the bowing come with it.
The sequel to Voices of Modernism, with the same fiery playing: an early quartet that sounds Beethovenish and a late one that sounds Mozartean.
An a cappella collection of hymns recorded with no limiting, compression or artificial reverb — unusually clear about the voice, and unforgiving about any note that strays.
My favourite piece of music in its first multichannel release, where for the first time I could hear the three pianos apart instead of one wall of sound.
Beethoven, Stravinsky, Rorem and Scearce across two IsoMike discs, in gripping performances and one of the best string quartet recordings I have heard.
The final instalment, middle of the road in both performance and sonics, and a closing verdict ranking all four Adelaide Ring titles against one another.
An IsoMike four-channel jazz recording made with baffled microphones, at the lowest level I had met on a commercial disc, where the ambience channels matter more than I expected.
Gould’s 1955 mono recording reverse-engineered into note data and replayed on a Disklavier direct to DSD: a stunning piano recording, and a performance that is his and yet subtly not.
A well played Tenth from an orchestra not to be dismissed as amateurs, and a faithful capture of the Sydney Opera House Concert Hall's difficult acoustics, warts included.
Soprano arias billed as rare and mostly not, sung with style and flair, with the voice imaged left of centre exactly where a soloist stands in a real hall.
The opera in the cycle I had always liked least, in a performance and recording that changed my mind — the best balanced of the four, and the one to sample multichannel SACD on.
The second Adelaide instalment, and the weakest: a faultless recording of a staging whose energy was largely visual, with stage water reading on the microphones as crackle.
Piano and tabla, and the rare SACD where I preferred the stereo mix — with an explanation from the producer of why the surround ambience was built the way it was.
The talk I gave at BankTech.06 on embedding SOA in a retail bank, reproduced from the slide deck, including the observation that NAB's ten architecture capabilities described an SOA while carefully avoiding the word.
The first instalment of the Adelaide Ring on SACD, reviewed by someone who sat in the hall: an emotional rather than physical Walküre, on a recording that may beat being there.
Installing and configuring Media Center 2005, the tuner and display setup, and the things the manual does not tell you.
Living with the finished machine: what worked, what did not, and what I would do differently.
The first part of a look at what is true and what is folklore in digital audio: sample rates, bit depth, and the arguments that will not go away.
The build itself — case, motherboard, tuners and the quiet-running compromises a machine that lives in a living room has to make.
A review of Cary Audio Design's Cinema 6 AV processor, with bench measurements alongside the listening.
The follow-up, not as well recorded as its predecessor, and with so little between the SACD and CD layers that I wondered whether they share a master.
Gould at his most accessible, playing the piano rather like a harpsichord — the best introduction to him on SACD, stray clicks and omnipresent hiss notwithstanding.
Ballads from 1958 with Bill Evans and Kenny Burrell, where the SACD layer reveals tape dropouts and saturation that the CD layer turns into something like clipping.
A 1965 television soundtrack that still sounds startlingly alive, hard-panned in the manner of early stereo, and emphatically not the kiddies’ music the cover suggests.
Hewitt plays the piano as a piano, prettily; the unconventional surround mix is the interesting part, with the double bass sitting almost wholly in the 0.1 channel.
The Marantz DV6500 universal player with the JLTi analogue-stage modification, measured and listened to against the standard machine.
A review of the Panasonic DVD-S97 universal player, including its video processing and how it handles progressive output.
Building a Windows Media Center Edition 2005 home theatre PC: what the platform could do in 2005, and choosing the parts.
The talk I prepared for The Enterprise Architecture Conference 2005 in Sydney, on where SOA sits inside an enterprise architecture — the March SOA talk grown into a case study of how MLC sold, governed and proof-of-concept-tested its way towards one.
The Microsoft Architect Council cut of my March 2005 SOA talk - the same deck reopened for twenty-eight seconds that June, the event line changed and the religion slide deleted, and delivered in Sydney on 3 August 2005.
The background presentation Kate Behan gave to open an ACS branch forum on SOA in June 2005, before a panel session I sat on — reproduced from her deck, which drew on my earlier SOA talk and closed by handing the room to the panellists.
A talk I gave at an SOA conference in Sydney in March 2005, arguing that SOA was in danger of being received as one more silver bullet, and that the way to avoid that was to treat it as a religion and go looking for converts.
Six reconstructed concertos from the set presented to Charles VI, recorded, edited and mastered in DSD, in a reading I found a shade too languid.
A review of the Denon DVD-3910 for MichaelDVD.
A review of the Denon DVD-1710 for MichaelDVD.
A review of the Microsoft Windows XP Media Center Edition 2005 for MichaelDVD.
A review of the NAD T513 for MichaelDVD.
Why signals that exceed digital full scale between samples clip in the reconstruction filter, how much headroom players actually leave, and what it does to the sound.
The last of the series: SACD against CD on the same titles, and a look at whether the format or the master is doing the work.
Turning the same measurements on vinyl: LP transfers against their CD counterparts, and where the audible differences really come from.
Recording the CD, DVD-A and SACD releases of one album through the same converter and comparing what came back — waveforms, levels and ultrasonic content.
The second part of the format comparison: spectral analysis of the same three transfers, and what the ultrasonic energy above 22kHz actually contains.
Closing the three-format comparison with the dynamic range figures, and what they say about mastering rather than about the formats themselves.
A short measurement note: harmonic distortion that turned out to belong to the amplifier rather than to any of the players feeding it.
The case-study talk I gave in July 2004 as Head of Architecture at MLC, on the journey from hard-to-justify EAI business cases to web services and the architecture that became our SOA — given at a conference the deck does not name.
A 2004 APC Magazine roundup of four Windows programs for watching and recording digital television in Australia, reproduced from the Word file as it was sent to the magazine, editorial scaffolding and all.
The same 2004 roundup after APC's Dan Warne had been through it, a third shorter, with a co-author added, the boxout cut and two of my mistakes fixed.
The third piece of my July 2004 APC batch, a Girder and TIRA tutorial with two boxouts, reproduced from the manuscript as it left my hands — with the draft's self-written brief and what changed between the two versions on the way to the deadline.
The myHTPC workshop from my July 2004 APC batch, reproduced from the manuscript that went to the magazine — the piece that was commissioned at the highest rate, abandoned on day one under an XMLTV heading, and finished across one long weekend.
The first version of the 0dBFS+ work: what six players and one amplifier actually did with peaks that exceed digital full scale.
A review of the Denon DVD-2200 for MichaelDVD.
Why most of my music DVDs did not sound as good as my CDs, traced through the waveforms of the same recordings in every format the discs offered.
The companion HighNote compilation, and the better sounding of the two — clean, airy and room-filling, with the CD layer clearly behind the DSD stereo.
A mid-priced HighNote compilation whose cheesy title and blurb undersell it: consistent instrumental tracks, mixed a little low, with the DSD layer tightening the bass.
Why a PC beat three set-top DVD players in my own living room, and what it took to build one that was quiet enough to sit beside them.
A review of the Linn Unidisk 2.1 for MichaelDVD.
A September 2003 talk on National Wealth Management's technology for financial advisers — the shift to holistic advice, the business system behind it, and AdviserCentral.
A review of the Denon DVD-2900 for MichaelDVD.
The talk I gave twice in 2003 — Sydney in July, Wellington in November — at BTELL's Enterprise Architecture Conference, on five years of implementing and embedding the architecture team at National Wealth Management, reproduced from the deck the conference CDs distributed.
The 30th Anniversary SACD ranked against a Quad LP, two earlier CD masterings and a bootleg DTS disc — seven versions of one album, each with its own sonic character.
Soft ballads with only hints of bluegrass, on a stereo hybrid where the SACD layer is mastered at least 3dB below the CD and the two make for genuinely different listening.
Chesky's jazz and R&B arrangements of pop tunes, with the rolled-off top end and barely used surround channels typical of the label's multichannel discs.
The Verve single-layer SACD against a battered LP and the Master Edition CD: more presence on the saxophone and voices, and enough resolution to expose tape faults the CD had hidden.
A review of the Linn Classik Movie System for MichaelDVD.
A review of the Pioneer DV-S733A for MichaelDVD, written with Tony Rogers.
A review of the Denon DVD-3800 for MichaelDVD.
A review of the Denon DVD-A1 for MichaelDVD, written with John Lee.
A review of the Sony DVP-NS905V for MichaelDVD.
The Region 4 DVD of An Officer And A Gentleman (1981), reviewed for MichaelDVD — 4 out of 5 overall.
The Region 4 DVD of What Women Want (2000), reviewed for MichaelDVD — 4 out of 5 overall.
The Region 4 DVD of Space Cowboys (2000), reviewed for MichaelDVD — 4 out of 5 overall.
The Region 4 DVD of The Goldberg Variations (1981), reviewed for MichaelDVD — 4 out of 5 overall.
The Region 4 DVD of The Living Daylights: Special Edition (1987), reviewed for MichaelDVD — 3.5 out of 5 overall.
The Region 4 DVD of The Truman Show (1998), reviewed for MichaelDVD — 4 out of 5 overall.
The Region 4 DVD of The English Patient (1996), reviewed for MichaelDVD — 5 out of 5 overall.
The Region 4 DVD of The Way We Were: Collector's Edition (1973), reviewed for MichaelDVD — 3.5 out of 5 overall.
The Region 4 DVD of Michael Ball: Live at the Royal Albert Hall (1999), reviewed for MichaelDVD — 3 out of 5 overall.
The Region 4 DVD of Andrew Lloyd Webber: Royal Albert Hall Celebration (1998), reviewed for MichaelDVD — 3.5 out of 5 overall.
The Region 4 DVD of Grey Owl, reviewed for MichaelDVD — 3 out of 5 overall.
The Region 4 DVD of Pride and Prejudice (1995), reviewed for MichaelDVD — 3 out of 5 overall.
The Region 4 DVD of Oasis-Familiar To Millions (2000), reviewed for MichaelDVD — 4 out of 5 overall.
The Region 4 DVD of Deep Purple-In Concert With The London Symphony Orchestra (1999), reviewed for MichaelDVD — 4 out of 5 overall.
The Region 4 DVD of Earl Klugh: The Jazz Channel Presents (2000), reviewed for MichaelDVD — 3.5 out of 5 overall.
The Region 4 DVD of Oasis ... There and Then (1996), reviewed for MichaelDVD — 3 out of 5 overall.
The Region 4 DVD of The Soul Conversation-Jazz Channel Presents (2000), reviewed for MichaelDVD — 3 out of 5 overall.
The Region 4 DVD of The Sound of Music (1965), reviewed for MichaelDVD — 3.5 out of 5 overall.
The Region 4 DVD of Bobby Womack: The Jazz Channel Presents (2000), reviewed for MichaelDVD — 3 out of 5 overall.
The Region 4 DVD of My Dog Skip (2000), reviewed for MichaelDVD — 5 out of 5 overall.
The Region 4 DVD of The Cell (2000), reviewed for MichaelDVD — 3.5 out of 5 overall.
The Region 4 DVD of James Galway - At The Waterfront (1999), reviewed for MichaelDVD — 3.5 out of 5 overall.
The Region 4 DVD of Gossip (2000), reviewed for MichaelDVD — 4 out of 5 overall.
The Region 4 DVD of Carole King: In Concert (1994), reviewed for MichaelDVD — 3.5 out of 5 overall.
The Region 4 DVD of The Martin, Ricky-Ricky Martin Video Collection (1999), reviewed for MichaelDVD — 2.5 out of 5 overall.
The Region 4 DVD of Cube (1997), reviewed for MichaelDVD — 3.5 out of 5 overall.
The Region 4 DVD of GalaxyQuest (1999), reviewed for MichaelDVD — 4 out of 5 overall.
The Region 4 DVD of James Bond: For Your Eyes Only (1981), reviewed for MichaelDVD — 4 out of 5 overall.
The Region 4 DVD of Franz Schubert — Winterreise (Bostridge/Drake), reviewed for MichaelDVD — 3.5 out of 5 overall.
The Region 4 DVD of Desperately Seeking Susan, reviewed for MichaelDVD — 3 out of 5 overall.
The Region 4 DVD of The Rocky Horror Picture Show, reviewed for MichaelDVD — 4.5 out of 5 overall.
The Region 4 DVD of Laurel and Hardy: The Music Box, reviewed for MichaelDVD — 3 out of 5 overall.
The Region 4 DVD of Arthur, reviewed for MichaelDVD — 3 out of 5 overall.
The Region 4 DVD of Jeffrey Osborne: The Jazz Channel Presents, reviewed for MichaelDVD — 4.5 out of 5 overall.
The Region 4 DVD of Sting - The Brand New Day Tour, reviewed for MichaelDVD — 3.5 out of 5 overall.
The Region 4 DVD of EarthScapes, reviewed for MichaelDVD — 2 out of 5 overall.
The Region 4 DVD of Paul Weller: Live at The Royal Albert Hall, reviewed for MichaelDVD — 4 out of 5 overall.
The Region 4 DVD of Hearst Castle: Building The Dream, reviewed for MichaelDVD — 2.5 out of 5 overall.
The Region 4 DVD of La Bohème, reviewed for MichaelDVD — 3.5 out of 5 overall.
The Region 4 DVD of Lou Rawls: The Jazz Channel Presents, reviewed for MichaelDVD — 3.5 out of 5 overall.
The Region 4 DVD of The Best of Wham! (1997), reviewed for MichaelDVD — 2.5 out of 5 overall.
The Region 4 DVD of Pleasantville, reviewed for MichaelDVD — 4.5 out of 5 overall.
The Region 4 DVD of I Dreamed Of Africa, reviewed for MichaelDVD — 3.5 out of 5 overall.
The Region 4 DVD of Loser, reviewed for MichaelDVD — 3 out of 5 overall.
The Region 4 DVD of Beloved, reviewed for MichaelDVD — 3.5 out of 5 overall.
The Region 4 DVD of Peter Frampton: Live In Detroit, reviewed for MichaelDVD — 4.5 out of 5 overall.
The Region 4 DVD of Anima Mundi, reviewed for MichaelDVD — 2.5 out of 5 overall.
The Region 4 DVD of Canyon Dreams, reviewed for MichaelDVD — 2.5 out of 5 overall.
The Region 4 DVD of Chronos, reviewed for MichaelDVD — 2.5 out of 5 overall.
A 1997 talk on why consumers were hesitating over online shopping, what that meant for bank delivery channels, and the privacy law Australia did not yet have.
A 1994 conference paper surveying how client/server systems were actually being built on open systems, from remote presentation through to distributed databases, and where transactions fit.
The AUUG'94 conference paper on how client/server systems were actually being built on open systems, from remote presentation to distributed databases, later revised for Oracle OpenWorld.
A 1993 assignment on how a conservative savings bank founded in 1851 lost its capital twice over through a merchant banking subsidiary — written by someone who had been working in its Treasury.
A 1993 AUUG conference paper on finding and fixing bottlenecks in relational database applications on UNIX, with three case studies benchmarking Oracle and Informix across RAID levels and Volume Manager configurations.
A 1993 syndicate assignment: forecast total returns for twelve asset classes across seven markets under five world scenarios, then run them through a mean-variance optimiser and argue with the answer.
The Common Fund’s tactical asset allocation scheme, and how Sanford C. Bernstein turned a dividend discount model into a stock selection discipline — written for Applied Portfolio Management in 1993.
Two questions from a 1993 Finance Law and Tax assignment: how the common law and the Banking Act define carrying on banking business, and the four circumstances in which a banker may disclose a customer’s affairs.
In 1987 five of us at Sydney University took Infocom's virtual machine apart to see how it worked. We did not expect it to matter to anyone else.
I have loved HP calculators all my life, and the HP 48 was the first I bought with my own hard earned money. In 1991 I taught mine the foreign exchange market and how to price a bond.
A program three of us wrote in 1991 that compiles and runs in eight languages, and what became of it.
Our 1991 USENIX paper showing that DES-based UNIX password encryption could be brute-forced, with an ECL hardware design that encrypted a password in 6 microseconds.
The longer version of our 1990 Optech paper, with the sections SunTech Journal cut, the libraries described one at a time, and the figures as we drew them.
Our 1990 SunTech Journal article on hedging the risk in an options book, and the distributed trading system we built at Optech to do it on a network of Sun workstations.
My 1987 honours thesis at the University of Sydney. A language for writing music down that reads like music rather than like code, and a system that performs it.
Five of us built one microprocessor board in 1987 and submitted it for two courses at once. It bridged a synthesiser and a VAX, and it was meant to be where Rubato came out.
This whole site is Spotlite, a free and open source Astro template for your own CV. Write each role once as a Markdown file and it builds the work history, the career timeline, the search index and two print-ready PDFs, so your CV and your website can never disagree with each other.
Fork it, clear out my content, and make it yours. MIT licensed.